WO2007062268A2 - Method and structure for magnetically-directed, self-assembly of three-dimensional structures - Google Patents

Method and structure for magnetically-directed, self-assembly of three-dimensional structures Download PDF

Info

Publication number
WO2007062268A2
WO2007062268A2 PCT/US2006/045633 US2006045633W WO2007062268A2 WO 2007062268 A2 WO2007062268 A2 WO 2007062268A2 US 2006045633 W US2006045633 W US 2006045633W WO 2007062268 A2 WO2007062268 A2 WO 2007062268A2
Authority
WO
WIPO (PCT)
Prior art keywords
magnetic field
force
permanent magnet
magnetic
magnets
Prior art date
Application number
PCT/US2006/045633
Other languages
French (fr)
Other versions
WO2007062268A8 (en
WO2007062268A3 (en
Inventor
David Patrick Arnold
Original Assignee
University Of Florida Research Foundation, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by University Of Florida Research Foundation, Inc. filed Critical University Of Florida Research Foundation, Inc.
Publication of WO2007062268A2 publication Critical patent/WO2007062268A2/en
Publication of WO2007062268A3 publication Critical patent/WO2007062268A3/en
Publication of WO2007062268A8 publication Critical patent/WO2007062268A8/en
Priority to US12/102,758 priority Critical patent/US8138868B2/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81C—PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
    • B81C1/00—Manufacture or treatment of devices or systems in or on a substrate
    • B81C1/00007—Assembling automatically hinged components, i.e. self-assembly processes
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B81—MICROSTRUCTURAL TECHNOLOGY
    • B81C—PROCESSES OR APPARATUS SPECIALLY ADAPTED FOR THE MANUFACTURE OR TREATMENT OF MICROSTRUCTURAL DEVICES OR SYSTEMS
    • B81C3/00—Assembling of devices or systems from individually processed components
    • B81C3/002—Aligning microparts
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L24/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L24/00—Arrangements for connecting or disconnecting semiconductor or solid-state bodies; Methods or apparatus related thereto
    • H01L24/93—Batch processes
    • H01L24/95—Batch processes at chip-level, i.e. with connecting carried out on a plurality of singulated devices, i.e. on diced chips
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L25/00—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof
    • H01L25/50—Multistep manufacturing processes of assemblies consisting of devices, each device being of a type provided for in group H01L27/00 or H01L29/00
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00—Apparatus or processes for manufacturing printed circuits
    • H05K3/30—Assembling printed circuits with electric components, e.g. with resistor
    • H05K3/303—Surface mounted components, e.g. affixing before soldering, aligning means, spacing means
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/80—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected
    • H01L2224/83—Methods for connecting semiconductor or other solid state bodies using means for bonding being attached to, or being formed on, the surface to be connected using a layer connector
    • H01L2224/838—Bonding techniques
    • H01L2224/83801—Soldering or alloying
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/93—Batch processes
    • H01L2224/95—Batch processes at chip-level, i.e. with connecting carried out on a plurality of singulated devices, i.e. on diced chips
    • H01L2224/95053—Bonding environment
    • H01L2224/95085—Bonding environment being a liquid, e.g. for fluidic self-assembly
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/93—Batch processes
    • H01L2224/95—Batch processes at chip-level, i.e. with connecting carried out on a plurality of singulated devices, i.e. on diced chips
    • H01L2224/95053—Bonding environment
    • H01L2224/95091—Under pressure
    • H01L2224/95092—Atmospheric pressure, e.g. dry self-assembly
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/93—Batch processes
    • H01L2224/95—Batch processes at chip-level, i.e. with connecting carried out on a plurality of singulated devices, i.e. on diced chips
    • H01L2224/9512—Aligning the plurality of semiconductor or solid-state bodies
    • H01L2224/95136—Aligning the plurality of semiconductor or solid-state bodies involving guiding structures, e.g. shape matching, spacers or supporting members
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/93—Batch processes
    • H01L2224/95—Batch processes at chip-level, i.e. with connecting carried out on a plurality of singulated devices, i.e. on diced chips
    • H01L2224/9512—Aligning the plurality of semiconductor or solid-state bodies
    • H01L2224/95143—Passive alignment, i.e. self alignment, e.g. using surface energy, chemical reactions, thermal equilibrium
    • H01L2224/95144—Magnetic alignment, i.e. using permanent magnetic parts in the semiconductor or solid-state body
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/93—Batch processes
    • H01L2224/95—Batch processes at chip-level, i.e. with connecting carried out on a plurality of singulated devices, i.e. on diced chips
    • H01L2224/9512—Aligning the plurality of semiconductor or solid-state bodies
    • H01L2224/95143—Passive alignment, i.e. self alignment, e.g. using surface energy, chemical reactions, thermal equilibrium
    • H01L2224/95145—Electrostatic alignment, i.e. polarity alignment with Coulomb charges
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2224/00—Indexing scheme for arrangements for connecting or disconnecting semiconductor or solid-state bodies and methods related thereto as covered by H01L24/00
    • H01L2224/93—Batch processes
    • H01L2224/95—Batch processes at chip-level, i.e. with connecting carried out on a plurality of singulated devices, i.e. on diced chips
    • H01L2224/9512—Aligning the plurality of semiconductor or solid-state bodies
    • H01L2224/95143—Passive alignment, i.e. self alignment, e.g. using surface energy, chemical reactions, thermal equilibrium
    • H01L2224/95146—Passive alignment, i.e. self alignment, e.g. using surface energy, chemical reactions, thermal equilibrium by surface tension
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01005—Boron [B]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01006—Carbon [C]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01015—Phosphorus [P]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01023—Vanadium [V]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01027—Cobalt [Co]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01033—Arsenic [As]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01078—Platinum [Pt]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/01—Chemical elements
    • H01L2924/01082—Lead [Pb]
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/011—Groups of the periodic table
    • H01L2924/01105—Rare earth metals
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/10—Details of semiconductor or other solid state devices to be connected
    • H01L2924/11—Device type
    • H01L2924/14—Integrated circuits
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/10—Details of semiconductor or other solid state devices to be connected
    • H01L2924/146—Mixed devices
    • H01L2924/1461—MEMS
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/15—Details of package parts other than the semiconductor or other solid state devices to be connected
    • H01L2924/151—Die mounting substrate
    • H01L2924/1515—Shape
    • H01L2924/15153—Shape the die mounting substrate comprising a recess for hosting the device
    • H01L2924/15155—Shape the die mounting substrate comprising a recess for hosting the device the shape of the recess being other than a cuboid
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/15—Details of package parts other than the semiconductor or other solid state devices to be connected
    • H01L2924/151—Die mounting substrate
    • H01L2924/15165—Monolayer substrate
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/19—Details of hybrid assemblies other than the semiconductor or other solid state devices to be connected
    • H01L2924/1901—Structure
    • H01L2924/1904—Component type
    • H01L2924/19041—Component type being a capacitor
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/19—Details of hybrid assemblies other than the semiconductor or other solid state devices to be connected
    • H01L2924/1901—Structure
    • H01L2924/1904—Component type
    • H01L2924/19042—Component type being an inductor
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/19—Details of hybrid assemblies other than the semiconductor or other solid state devices to be connected
    • H01L2924/1901—Structure
    • H01L2924/1904—Component type
    • H01L2924/19043—Component type being a resistor
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/19—Details of hybrid assemblies other than the semiconductor or other solid state devices to be connected
    • H01L2924/191—Disposition
    • H01L2924/19101—Disposition of discrete passive components
    • H01L2924/19105—Disposition of discrete passive components in a side-by-side arrangement on a common die mounting substrate
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
    • H01L2924/30—Technical effects
    • H01L2924/301—Electrical effects
    • H01L2924/3025—Electromagnetic shielding
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
    • H05K2201/08—Magnetic details
    • H05K2201/083—Magnetic materials
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
    • H05K2201/10—Details of components or other objects attached to or integrated in a printed circuit board
    • H05K2201/10613—Details of electrical connections of non-printed components, e.g. special leads
    • H05K2201/10621—Components characterised by their electrical contacts
    • H05K2201/10636—Leadless chip, e.g. chip capacitor or resistor
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2201/00—Indexing scheme relating to printed circuits covered by H05K1/00
    • H05K2201/10—Details of components or other objects attached to or integrated in a printed circuit board
    • H05K2201/10613—Details of electrical connections of non-printed components, e.g. special leads
    • H05K2201/10621—Components characterised by their electrical contacts
    • H05K2201/10674—Flip chip
    • H—ELECTRICITY
    • H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K2203/00—Indexing scheme relating to apparatus or processes for manufacturing printed circuits covered by H05K3/00
    • H05K2203/04—Soldering or other types of metallurgic bonding
    • H05K2203/048—Self-alignment during soldering; Terminals, pads or shape of solder adapted therefor
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P70/00—Climate change mitigation technologies in the production process for final industrial or consumer products
    • Y02P70/50—Manufacturing or production processes characterised by the final manufactured product
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/4902—Electromagnet, transformer or inductor
    • Y10T29/49075—Electromagnet, transformer or inductor including permanent magnet or core
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/49—Method of mechanical manufacture
    • Y10T29/49002—Electrical device making
    • Y10T29/49117—Conductor or circuit manufacturing
    • Y10T29/49124—On flat or curved insulated base, e.g., printed circuit, etc.
    • Y10T29/4913—Assembling to base an electrical component, e.g., capacitor, etc.
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/53—Means to assemble or disassemble
    • Y10T29/5313—Means to assemble electrical device
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T29/00—Metal working
    • Y10T29/53—Means to assemble or disassemble
    • Y10T29/5313—Means to assemble electrical device
    • Y10T29/53196—Means to apply magnetic force directly to position or hold work part

Definitions

  • This invention is directed to the self-assembly of three-dimensional structures, and more particularly, to the self-assembly of three-dimensional structures for integrated circuits utilizing shaped magnetic fields.
  • Fig. IA a schematic of a known assembly process is shown.
  • Semiconductor devices are batch fabricated using wafers 10. After microfabrication, the wafers are diced and possibly packaged into subcomponents 12.
  • passive electrical components such as capacitors, inductors, and resistors, as well as circuit boards 14 are fabricated. After individual fabrication, all of the system subcomponents are assembled serially onto the circuit boards utilizing human manipulation, or more commonly robotic "pick and place" systems to form the completed electrical circuit board 15. This method has been satisfactory; however, it suffers from the disadvantage that the large number of components that can be batch manufactured overwhelm the throughput capabilities for the serial back-end packaging and assembly.
  • the throughput is limited by the number and speed of the robotic manipulators.
  • the shrinking physical size of the microelectronics, down to the micro- or nanoscale in many applications, requires precise manipulation. As components become smaller, the absolute alignment positioning tolerances scale equivalently; sometimes beyond the capabilities of robotic manipulation.
  • Self-assembly has been utilized to a small extent during the packaging and preparation process when forming components onto substrates.
  • Self-assembly is the autonomous organization of components into patterns or structures without human intervention. It is the assembly of parts onto a fixed substrate or the assembly of homogeneous or heterogeneous mixtures of parts one to another. The process is inherently stochastic, relying on the random distribution, mixing and physical interactions between the parts.
  • the self-assembly processes are governed by two fundamental forces, one being played against the other. Namely, the two forces are the mixing forces causing the large-scale mechanical movement between the parts to be assembled and short-range bonding forces causing the parts to assemble to one another when in close proximity.
  • the short range bonding force must be greater than the mixing force to provide a stable connection.
  • the short range bonding force must also be sufficient to overcome other external forces that may act to separate the parts, such as gravity, surface tension, buoyancy, electrostatic forces or the like. Alignment of the parts in self-assembly is typically dependent on minimization of the total free energy.
  • pattern electrodes have been formed on the surface of at least one of the parts to create electric field traps to capture and surface mount components and LEDs on silicon substrates.
  • This method has been satisfactory; however, it requires the formation of an electrical circuit in a desired pattern on the substrate.
  • This adds complexity to the structure of a substrate is often substrate-limited, i.e., is too difficult to use between two free-floating bodies, and requires the input of energy.
  • One way of overcoming this shortcoming is to create direct forces between the component and the substrate such as magnetic forces. It is known in the art to use magnetic forces to self-assemble 50 ⁇ m nickel disks coated with immobilized biomaterials into an array of nickel disk pattern on the substrate. However, in the prior art, the magnetic forces were the result of the entire structure being a magnet where the structures were attracted to each other, but there is no control over selectivity, or interaction. Furthermore, the magnetic approach was also limited to substrate bonding, not to free floating bodies.
  • capillary forces have also been used to drive self-assembly.
  • the capillary forces become dominant.
  • the hydrophilicity of various regions of a surface is controlled to pattern liquid films on a substrate.
  • the pad spontaneously wets, and capillary forces draw the part into alignment, thereby minimizing the fluidic interfacial surface energy.
  • This technique has come into vogue to assemble small parts onto planar surfaces with submicron precision for micromirror arrays, inductors and micropumps by way of example.
  • the method must restrict part bonding to a unique physical orientation between the two bodies to be bonded.
  • process yield is improved by minimizing the number of misaligned, misfit or incorrectly bonded (e.g., upside down) bonds.
  • Orientational uniqueness is necessary to ensure physically symmetric parts are bonded in the desired orientation to allow complex mating of interconnecting structures.
  • bonding forces would be sufficient to dominate the mixing forces even if incorrectly aligned, hi other words, certain incorrect orientations may result in a local minimization of energy, and the mixing energy is insufficient to move the part into the desired orientation to achieve the global energy minimum. Furthermore, for bonding approaches that have geometric symmetry, energy minimization may occur even in more than one physical orientation.
  • the self-assembly method must also lend itself to bonding selectivity, i.e., that the desired part bond with its intended mating part, but not with a third unintended part.
  • Each of the gravity, electrostatic, electric field trap, and capillary methods can be adapted to provide bonding selectivity based on geometric shape, electromagnetic properties, surface and hydrophilicity between the parts.
  • a self-assembly process should also enable inter-part bonding, namely that free floating parts bond to other free floating parts, rather than to fixed substrates.
  • inter-part bonding the electric field method becomes inapplicable with its requirement of the application of an electric charge to at least one of the bodies.
  • Inter-part bonding further requires the ability to bond in any arbitrary direction. Because of this, gravity-driven processes are inapplicable because gravity only acts in one direction. A collection of free floating parts would have no driving force to bond to one another unless oriented so that gravity is in the direction of at least one of the parts. As a result, short-range bonding forces must exist intrinsically between the parts, not from some externally applied source.
  • a secondary challenge for inter-part bonding is preventing agglomeration, where parts of a similar type inadvertently bond to each other rather than to the specified receptor site.
  • capillary-driven assembly is inapplicable because agglomeration requires that there are no short range bonding forces between similar parts, while insuring there are bonding forces between dissimilar parts. If parts of a first type must have a wetted receptor, they will agglomerate to each other while the "dry" second type would not agglomerate.
  • a first body is provided with a single magnet or plurality of magnets disposed on the body to form a spatially varying magnetic field in a first predetermined pattern.
  • the magnets are of a first polarity.
  • a second body has a single magnet or plurality of magnets disposed on the body to form a spatially varying magnetic field in a second pattern, which is complimentary to the first pattern.
  • the second pattern is the mirror image of the first pattern.
  • the magnet or magnets of the second body may either be magnetically hard, having a magnetic polarity opposite to the polarity of the first magnet or magnets, or may be magnetically soft in which it becomes magnetized in the presence of the magnetic field from the first pattern.
  • a magnetically hard magnet, or permanent magnet has a permanent magnetic polarization.
  • a magnetically soft magnet, or soft magnet becomes magnetized, and exhibits a magnetic field, in the presence of another magnetic field.
  • the size and arrangement of the first pattern and second pattern being sufficient so that when the first pattern is in close proximity to the second pattern, and substantially aligned, the attraction force between the first magnetic field pattern and the second magnetic field pattern is sufficient to overcome a mixing force.
  • the magnetic attraction force resulting from the interaction of the first magnetic field and the second magnetic field aligns the two bodies and bonds the two bodies. Full alignment of the two bodies with respect to each other results in an energy minimum, resulting in a stable physical orientation.
  • a plurality of magnets is formed in at least one of the first body or second body.
  • a single magnet with a specific physical shape is formed in at least one of the first body or second body.
  • one or more magnetic regions on the first body and/or second body are spatially magnetized to form the first or second shaped magnetic field pattern.
  • the orientation of the first magnetic field pattern relative to the second magnetic field pattern causes the first body to be uniquely oriented and bonded to the second body.
  • a first body is formed with a single magnet or plurality of magnets disposed to produce a first magnetic field having a first predetermined pattern.
  • a second body is formed with a single magnet or plurality of magnets to produce a second pattern complimentary to the first pattern.
  • the first body and second body are mixed together.
  • the first body being attracted to the second body when in sufficient proximity for an attraction between the first shaped magnetic field pattern to the second shaped magnetic field pattern to overcome a mixing force.
  • the attraction between the first shaped magnetic field pattern and second shaped magnetic field pattern overcomes the mixing force when the first pattern substantially aligns with the second pattern.
  • the full alignment of the first body and the second body results in an energy minimization and a stable bonding arrangement.
  • Fig. IA is a schematic diagram of a method for serial robotic self-assembly of sub-components in accordance with the prior art
  • Fig. IB is a schematic diagram of a method for parallel self-assembly in accordance with the prior art
  • Figs. 2A-2E are schematic diagrams of prior art self-assembly methods for components on a substrate;
  • FIG. 3 is an exploded perspective view of a self-assembled circuit constructed in accordance with the invention.
  • Fig. 4 is a graphical representation of the magnetic forces and potential energy between two uniformly magnetized permanent magnets for demonstrating an aspect of the invention
  • FIG. 5 is a schematic and graphical representation of the magnetic forces at work in accordance with the invention.
  • Figs. 6A-6E show a schematic representation of the fabrication of wafers in accordance with the invention.
  • an assembly generally indicated as 30, includes a first member 32, a second member 34 and a third member 36.
  • First member 32 is a printed circuit board; the circuit having a generic flip chip circuit and capacitor by way of example mounted thereon.
  • Circuit board 32 is provided with circuit structure including wiring or trace leads 38 conductively coupled to solder bumps 40 to allow electrical connection with other members 34, 36.
  • Circuit board 32 (interchangeably referred to as first member 32) includes a first plurality of magnets 42 arranged in a pattern 44 to provide a shaped magnetic field.
  • Circuit board 32 also includes a second plurality of magnets 46 arranged in a second pattern 48.
  • Second member 34 in this embodiment a flip chip, is formed with a plurality of magnets 50 thereon and solder bumps 52. Magnets 50 are provided in a predetermined pattern 54, which is the mirror image of pattern 44 to provide a mirror shaped magnetic field.
  • member 36 a capacitor in this example, includes solder bumps 56 and a plurality of magnets 58 in a pattern 60 which is the mirror image of pattern 48.
  • Magnetic forces arise between the patterns of magnets as a result of the interaction of the magnetic fields between any two magnets.
  • the magnetic fields are related to the material. While all materials have magnetic properties, what are commonly referred to as magnets are typically ferromagnetic in nature and can be classified as either hard or soft magnets. Hard magnetic materials possess a strong permanent magnetization, while soft magnetic materials incur a strong magnetization only upon the application of an external magnetic field. The use of different magnetic materials possessing different magnetic properties and strengths provides flexibility in the design.
  • a magnetic "lock and key” matching mechanism By utilizing complimentary magnetic field patterns, a magnetic "lock and key” matching mechanism is provided.
  • the size, shape, material type, and number of the individual magnets can be used to control the total magnetic patterns of the magnets, resulting in complex magnetic force field interactions, permitting a degree of pattern- matching between the components.
  • agglomeration is prevented because the individual magnets for any given component type are magnetized in the same direction ⁇ e.g., all having north or south polarities for the hard magnets). Jn additional embodiments, more complicated magnetic field patterns are utilized with agglomeration prevented as the magnetic attraction between parts of the same type are lower than the mixing force used. Thus, parts of the same type will repel each other, increasing the overall speed of the matching process while preventing misalignment of two bodies.
  • FIG. 4 For all but the simplest geometries, finite-element methods axe typical employed and for finite-element modeling, the method of virtual work has been shown to be the most precise.
  • the magnetic force is calculated by the derivative of the magnetic energy, U , with respect to a virtual displacement, ds:
  • the energy is related to the magnetic field distribution B by,
  • Magnetic pattern-matching is possible by combining the interactions of multiple magnets, as depicted in Fig. 5.
  • a plot of potential energy of the system versus lateral displacement, d exhibits several local minima, as individual magnets align, but only one global minimum, where all the magnets align. Physically, as the arrays shift with respect to each other, overlap of individual magnets may cause small bonding forces. However, the peak bonding force for the system is not reached until all magnets are acting in parallel. This same effect would apply for rotational misalignment, denoted ⁇ , and therefore could be used to realize orientational uniqueness.
  • This concept can also be extended to achieve bonding selectivity by considering the potential energy between different magnetic patterns. As dissimilar patterns overlap, individual magnets may cause small bonding forces, the parts will continue to mix until a part with the correct pattern fills the vacancy, thereby minimizing the total free energy. Again, by setting the mixing force higher than any attraction other than that provided by full alignment, the correct orientation will be self-selecting. In an embodiment, if magnets within the pattern are of different polarity, the patterns could cause repulsion between two bodies unless orientation between the patterns was correct so that all magnets attracted all opposed magnets. [0047] Referring back to Fig.
  • a first body such as circuit board 32
  • a desired matching body such as flip chip 34
  • a pattern 54 of a plurality of magnets 50 is provided with a pattern 54 of a plurality of magnets 50.
  • Magnets 50 are the opposite in polarity of magnets 42, although all of magnets 50 need not be the same polarity.
  • Magnets 50 and/or magnets 42 are hard magnets. However, either one of magnets 50 or 42 may be hard magnets, while the other is a soft magnet.
  • Member 32 and member 34 are mixed with each other.
  • second member 36 thrown into the same mixing process would, in parallel, become attracted to circuit board 32 because of the complementary magnetic patterns mirror image magnet patterns 48, 60.
  • capacitor 36 and flip chip 34 are self-selecting for their appropriate position relative to circuit board 32.
  • circuit board 32 were in fact broken into two pieces so that one half of circuit board 32 would be self-selecting with flip chip 34 while the other half would be self-selecting with capacitor 36 to prevent misfit or disorientation.
  • a patterned magnetic field is needed. Therefore, it is within the scope of the invention to provide a patterned magnetic field from a single magnet having a unique physical shape attracting a second single magnet of mirrored unique physical shape.
  • a third manner to obtain the patterned magnetic field is to provide a single physical magnet with varying magnetic properties (magnetization pattern) within itself in the desired pattern.
  • various combinations of permanent magnets, soft magnets, magnet arrays, magnet shapes, magnet magnetization profiles, and magnet patterns can be used to achieve a desired magnetic field pattern.
  • the magnetic structures are relatively small in volume as compared to the bodies in which they reside and therefore large amounts are not required reducing the relative cost.
  • the magnetic processing as will be described below, can be performed in batch operations.
  • micromagnetic components can be integrated at pattern by electrodeposition as seen in Figs. 6A through 6E.
  • the micro-magnets are patterned generally through photolithography.
  • a substrate 100 is provided at step 6 A with a deposited seed layer 102.
  • This conductive seed layer 102 is a thin layer of 0.1 ⁇ m.
  • step 6B small geometric shapes, having a height in the micrometer to millimeter range, are patterned into a photoresist layer 104, serving as the electroplating mold.
  • step 6C magnetic materials 106 are electroplated into the mold formed by photoresist layer 104.
  • the mold and seed layer 102 are removed by wet etching as known in the art.
  • the wafer is diced as known in the art.
  • This process is simple, low cost and CMOS compatible and is efficient for integrating a variety of magnetic materials with sufficient thickness (1 ⁇ m to 100 ⁇ m +) to provide useful magnetic fields.
  • Many different thick film electroplated permanent magnet materials have been developed for MEMS applications possessing a wide range of magnetic strengths, which would lend themselves to the process.
  • the bodies will be self-selecting and self-orienting to each other so that only the correct bodies in the correct orientations will bond in a mixing process, whether wet or dry.
  • the first magnetic field on the first body can be n- fold symmetric and the second magnetic field on the second body can be n-fold symmetric such that there are n orientations that the second body can be fully aligned and bonded with the first body.
  • the complementary first and second magnetic fields are asymmetric such that only one orientation of the first and second bodies results in full alignment and bonding.
  • a structure can have additional bodies that can align and bond to the second body, or any other body of the structure, due to magnetic fields on the additional bodies and the bodies to which the additional bodies align and bond.
  • a robot structure can have a torso that aligns and bonds with a right arm, a left arm, a right leg, a left leg, and a head.
  • Each of the parts, or bodies can selectively bond to the torso such that each part bonds only to the appropriate location and not to other locations.
  • a right hand, a left hand, a right foot, and a left foot can align and bond with the right arm, the left arm, the right leg, and the left leg, respectively.
  • the alignment and the bonding can be done in stages or simultaneously. In this way, a plurality of torso and a corresponding plurality of associated parts could be mixed such that the robots are self-assembled.
  • other structures such as MEMS structures, could be assembled. Such structures could include a variety of parts to be assembled, such as gears, blocks, levers, and other structures that can be held together via magnets incorporated with the parts.
  • the first body and second body that will be in contact after alignment and bonding can incorporate other attachment and/or connectivity means, such as glues for mechanical adhesion and solder bumps for electrical connectivity or bonding.
  • attachment and/or connectivity means such as glues for mechanical adhesion and solder bumps for electrical connectivity or bonding.
  • solder bumps can be used such that heating after alignment and bonding can cause a portion of the first body to be soldered to a portion of the second body.
  • glue can be used such that heating after alignment and bonding can cause a portion of the first body to be glued to a portion of the second body.
  • shielding material can be incorporated with the first and/or second body to shield the magnetic fields of the first and/or second body from portions of the aligned and bonded structure or other objects proximate to the structure.
  • shielding materials are well known in the art.
  • soft magnetic materials can be used as shielding.
  • a layer of soft magnetic material can be placed on one or more bodies and then the magnets for the body grown on the soft magnetic material layer such that the portion of the body below the layer is shielded from the magnetic fields of the magnets grown on the layer.
  • demagnetizable magnets and/or magnetic materials can be used such that after alignment and bonding, and optional implementation of additional attachment means, the demagnetizable magnets and/or magnetic material can be demagnetized, hi an example, magnets and/or magnetic material that can be demagnetized by heating can be used. Such materials are well known in the art. hi a specific embodiment, magnets and/or magnetic materials that can be demagnetized by heating to demagnetization temperatures under 500 0 C can be used.
  • the magnetic attraction force between two bodies are at least as great as the weight force of the body free to move, and at least as great as the weight force of the lightest body if both bodies are free to move.
  • the magnetic attraction force is two to ten as great as the weight force of the body free to move, and at least two to ten as great as the weight force of the lightest body if both bodies are free to move.

Abstract

A magnetically directed, self-assembled structure has a first body. The first body includes a single magnet or plurality of magnets disposed thereon to form a spatially variable magnetic field in a first predetermined pattern. A second body has a single magnet or plurality of magnets disposed thereon to form a spatially variable magnetic field in a second predetermined pattern. The second predetermined pattern is complementary to the first pattern. The first body is attracted to the second body with an attractive force greater than a mixture force such that the first body and second body are fully aligned to each other and bonded together.

Description

METHOD AND STRUCTURE FOR MAGNETICALLY-DIRECTED, SELF- ASSEMBLY OF THREE-DIMENSIONAL STRUCTURES
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims the benefit of U.S. Provisional Patent Application Serial No. 60/740,139, filed November 28, 2005, which is hereby incorporated by reference in its entirety, including all tables, drawings, and figures.
BACKGROUND OF THE INVENTION
[0002] This invention is directed to the self-assembly of three-dimensional structures, and more particularly, to the self-assembly of three-dimensional structures for integrated circuits utilizing shaped magnetic fields.
[0003] Over the past few decades, advances in the field of electronic and photonic devices for signal processing wireless communication, computing and the like have become more complex as they become more highly integrated. Most systems are an amalgam of heavily integrated microsystems. These systems are enabled by careful integration of subsystems of various physical size and function into compact modular devices. By way of example, the cellular phone tightly integrates CMOS electronics, RF components, photonics, micro-electro-mechanical systems (MEMS), passive discrete components, power supplies and circuit boards to enable wireless communication, data processing/storage and signal processing functionalities. The trend is for smaller, more compact, more integrated and more complex devices.
[0004] It is currently known in the art to create these devices by separately fabricating each of the components, through mutually incompatible processes, and then assembling into the sub-assemblies. For example, the semiconductor devices are batch fabricated using wafers having hundreds or thousands of individual components.
[0005] Reference is made to Fig. IA in which a schematic of a known assembly process is shown. Semiconductor devices are batch fabricated using wafers 10. After microfabrication, the wafers are diced and possibly packaged into subcomponents 12. In parallel with the semiconductor processing, passive electrical components such as capacitors, inductors, and resistors, as well as circuit boards 14 are fabricated. After individual fabrication, all of the system subcomponents are assembled serially onto the circuit boards utilizing human manipulation, or more commonly robotic "pick and place" systems to form the completed electrical circuit board 15. This method has been satisfactory; however, it suffers from the disadvantage that the large number of components that can be batch manufactured overwhelm the throughput capabilities for the serial back-end packaging and assembly. Because of the serial nature, the throughput is limited by the number and speed of the robotic manipulators. Secondly, the shrinking physical size of the microelectronics, down to the micro- or nanoscale in many applications, requires precise manipulation. As components become smaller, the absolute alignment positioning tolerances scale equivalently; sometimes beyond the capabilities of robotic manipulation.
[0006] Lastly, for sub-millimeter parts, the adhesion forces between the part and the manipulator are significant compared to gravity, resulting in a sticking problem.
[0007] Self-assembly has been utilized to a small extent during the packaging and preparation process when forming components onto substrates. Self-assembly is the autonomous organization of components into patterns or structures without human intervention. It is the assembly of parts onto a fixed substrate or the assembly of homogeneous or heterogeneous mixtures of parts one to another. The process is inherently stochastic, relying on the random distribution, mixing and physical interactions between the parts.
[0008] The self-assembly processes are governed by two fundamental forces, one being played against the other. Namely, the two forces are the mixing forces causing the large-scale mechanical movement between the parts to be assembled and short-range bonding forces causing the parts to assemble to one another when in close proximity. To maintain a bond, the short range bonding force must be greater than the mixing force to provide a stable connection. The short range bonding force must also be sufficient to overcome other external forces that may act to separate the parts, such as gravity, surface tension, buoyancy, electrostatic forces or the like. Alignment of the parts in self-assembly is typically dependent on minimization of the total free energy.
[0009] It is also known in the art to effect mixing by fluid flow (typically for wet assembly) or by vibration energy (typically for dry assembly). Short-range bonding forces have taken the forms of gravity, electrostatic forces, magnetic forces, and capillary forces (as seen in Fig. 2). It should be noted that the forces need merely be sufficient to temporarily hold two pieces of interest together even in the presence of the mixing forces. Once the parts have been assembled, permanent, mechanical and electrical connections can be made through the curing of polymer-based adhesives or reflowing of solder bumps.
[0010] More particularly, it is known to use electrostatic forces to more efficiently direct and hold one part to another. In one prior art embodiment, pattern electrodes have been formed on the surface of at least one of the parts to create electric field traps to capture and surface mount components and LEDs on silicon substrates. This method has been satisfactory; however, it requires the formation of an electrical circuit in a desired pattern on the substrate. This adds complexity to the structure of a substrate, is often substrate-limited, i.e., is too difficult to use between two free-floating bodies, and requires the input of energy.
[0011] One way of overcoming this shortcoming is to create direct forces between the component and the substrate such as magnetic forces. It is known in the art to use magnetic forces to self-assemble 50 μm nickel disks coated with immobilized biomaterials into an array of nickel disk pattern on the substrate. However, in the prior art, the magnetic forces were the result of the entire structure being a magnet where the structures were attracted to each other, but there is no control over selectivity, or interaction. Furthermore, the magnetic approach was also limited to substrate bonding, not to free floating bodies.
[0012] To overcome the shortcomings of these self-assembly structures and methods, capillary forces have also been used to drive self-assembly. At small scales, the capillary forces become dominant. The hydrophilicity of various regions of a surface is controlled to pattern liquid films on a substrate. When a hydrophilic contact pad on one side of a part comes in contact with a liquid droplet, the pad spontaneously wets, and capillary forces draw the part into alignment, thereby minimizing the fluidic interfacial surface energy. This technique has come into vogue to assemble small parts onto planar surfaces with submicron precision for micromirror arrays, inductors and micropumps by way of example.
[0013] These techniques and methods for manufacture have been satisfactory; however, they do not match the full functionality offered by robotic or human part manipulation such as orientational uniqueness, bonding selectivity, or inter-part bonding. As a result, they limit the basic logical design rules available for a designer in the self-assembly process.
[0014] To provide orientational uniqueness, the method must restrict part bonding to a unique physical orientation between the two bodies to be bonded. As a result, process yield is improved by minimizing the number of misaligned, misfit or incorrectly bonded (e.g., upside down) bonds. Orientational uniqueness is necessary to ensure physically symmetric parts are bonded in the desired orientation to allow complex mating of interconnecting structures.
[0015] In the prior art, bonding forces would be sufficient to dominate the mixing forces even if incorrectly aligned, hi other words, certain incorrect orientations may result in a local minimization of energy, and the mixing energy is insufficient to move the part into the desired orientation to achieve the global energy minimum. Furthermore, for bonding approaches that have geometric symmetry, energy minimization may occur even in more than one physical orientation.
[0016] The gravity driven self-assembly process has attempted to overcome this issue. This is done by giving a specific shape to the receptor site hole. However, these approaches require parts with large scale asymmetrical physical geometries, adding cost and complexity to the batch manufacture process, hi the capillary driven self-assembly method, asymmetric bonding interfaces have been implemented, but the alignment precision decreased and the process yields dropped by nearly 70%. The drop in yield is attributed to local energy minima creating misfits and the reduced precision was attributed to a less sharp dip in the energy curve.
[0017] The self-assembly method must also lend itself to bonding selectivity, i.e., that the desired part bond with its intended mating part, but not with a third unintended part. Each of the gravity, electrostatic, electric field trap, and capillary methods can be adapted to provide bonding selectivity based on geometric shape, electromagnetic properties, surface and hydrophilicity between the parts.
[0018] By way of example, for capillary driven assembly methods, a method has been developed for activating or deactivating certain receptor sites for the self-assembly of different components using sequential steps. Although allowing bonding selectivity, it requires substantial processing and precludes parallel assembly of heterogeneous mixtures. Furthermore, this sequential process lengthens the assembly process as a function of the number of different components.
[0019] For a gravity driven self-assembly, shape-matching techniques have been used to effect bonding selectivity for parallel self-assembly of a heterogeneous mixture of three different parts. It is comparable to the approach of a square block, which will not fit, into the proverbial circular hole. However, the number of mutually exclusive shapes may be limited and chip real estate may be wasted as a result of the need for size differentiation as one shape differentiator. Furthermore, the machining of arbitrarily shaped parts imposes additional processing complexity and cost. Therefore, the prior art provides no real solution for the bonding selectivity issue and the requirement in more complex applications for sequential selective bonding in a parallel process.
[0020] A self-assembly process should also enable inter-part bonding, namely that free floating parts bond to other free floating parts, rather than to fixed substrates. With respect to inter-part bonding, the electric field method becomes inapplicable with its requirement of the application of an electric charge to at least one of the bodies.
[0021] Inter-part bonding further requires the ability to bond in any arbitrary direction. Because of this, gravity-driven processes are inapplicable because gravity only acts in one direction. A collection of free floating parts would have no driving force to bond to one another unless oriented so that gravity is in the direction of at least one of the parts. As a result, short-range bonding forces must exist intrinsically between the parts, not from some externally applied source.
[0022] A secondary challenge for inter-part bonding is preventing agglomeration, where parts of a similar type inadvertently bond to each other rather than to the specified receptor site. As a result, capillary-driven assembly is inapplicable because agglomeration requires that there are no short range bonding forces between similar parts, while insuring there are bonding forces between dissimilar parts. If parts of a first type must have a wetted receptor, they will agglomerate to each other while the "dry" second type would not agglomerate. [0023] For a capillary-driven self-assembly approach, it has been demonstrated that a two-step sequential self-assembly of encapsulated LED structures using shape- and solder-directed processes of free floating parts may overcome the inter-part bonding issue. The agglomeration problem is overcome by recessing the wetted receptor sites and cavities and limiting access to only the smaller parts that are intended to be bonded. Solder may also be used as the bonding liquid in a way that solid solder bumps are patterned at the wafer level and heated to melt to form wetted contacts on each of the individual components. When cooled, the solder also serves as the permanent electrical and mechanical contact. This process has been shown to have potential to be satisfactory, however, it suffers from the drawback that it requires sequential assembly steps and the limitation of a single electrical contact between the individual parts and the requirement for parts of dissimilar size to prevent agglomeration.
[0024J Accordingly, a method and structure for overcoming the shortcomings of the prior art and allowing self-assembly between two bodies while providing orientational uniqueness, bonding selectivity and inter-part bonding is desired.
BRIEF SUMMARY OF THE INVENTION
[0025J hi order to effect self-assembly, a first body is provided with a single magnet or plurality of magnets disposed on the body to form a spatially varying magnetic field in a first predetermined pattern. In an embodiment, the magnets are of a first polarity. A second body has a single magnet or plurality of magnets disposed on the body to form a spatially varying magnetic field in a second pattern, which is complimentary to the first pattern. In an embodiment, the second pattern is the mirror image of the first pattern.
[0026] The magnet or magnets of the second body may either be magnetically hard, having a magnetic polarity opposite to the polarity of the first magnet or magnets, or may be magnetically soft in which it becomes magnetized in the presence of the magnetic field from the first pattern. A magnetically hard magnet, or permanent magnet, has a permanent magnetic polarization. A magnetically soft magnet, or soft magnet, becomes magnetized, and exhibits a magnetic field, in the presence of another magnetic field. The size and arrangement of the first pattern and second pattern being sufficient so that when the first pattern is in close proximity to the second pattern, and substantially aligned, the attraction force between the first magnetic field pattern and the second magnetic field pattern is sufficient to overcome a mixing force. The magnetic attraction force resulting from the interaction of the first magnetic field and the second magnetic field aligns the two bodies and bonds the two bodies. Full alignment of the two bodies with respect to each other results in an energy minimum, resulting in a stable physical orientation.
[0027] In one embodiment of the invention, a plurality of magnets is formed in at least one of the first body or second body. In another embodiment, a single magnet with a specific physical shape is formed in at least one of the first body or second body. In a third embodiment, one or more magnetic regions on the first body and/or second body are spatially magnetized to form the first or second shaped magnetic field pattern. In an embodiment, the orientation of the first magnetic field pattern relative to the second magnetic field pattern causes the first body to be uniquely oriented and bonded to the second body.
[0028] During use, a first body is formed with a single magnet or plurality of magnets disposed to produce a first magnetic field having a first predetermined pattern. A second body is formed with a single magnet or plurality of magnets to produce a second pattern complimentary to the first pattern. The first body and second body are mixed together. The first body being attracted to the second body when in sufficient proximity for an attraction between the first shaped magnetic field pattern to the second shaped magnetic field pattern to overcome a mixing force. The attraction between the first shaped magnetic field pattern and second shaped magnetic field pattern overcomes the mixing force when the first pattern substantially aligns with the second pattern. The full alignment of the first body and the second body results in an energy minimization and a stable bonding arrangement.
BRIEF DESCRIPTION OF THE DRAWINGS
[0029] For a fuller understanding of the invention, reference is had to the following description taken in connection with the accompanying drawings in which:
[0030] Fig. IA is a schematic diagram of a method for serial robotic self-assembly of sub-components in accordance with the prior art;
[0031] Fig. IB is a schematic diagram of a method for parallel self-assembly in accordance with the prior art; [0032] Figs. 2A-2E are schematic diagrams of prior art self-assembly methods for components on a substrate;
[0033] Fig. 3 is an exploded perspective view of a self-assembled circuit constructed in accordance with the invention;
[0034] Fig. 4 is a graphical representation of the magnetic forces and potential energy between two uniformly magnetized permanent magnets for demonstrating an aspect of the invention;
[0035] Fig. 5 is a schematic and graphical representation of the magnetic forces at work in accordance with the invention;
[0036] Figs. 6A-6E show a schematic representation of the fabrication of wafers in accordance with the invention.
DETAILED DESCRIPTION OF THE INVENTION
[0037] Reference is now made a specific embodiment, shown in Fig. 3, in which an assembly, generally indicated as 30, includes a first member 32, a second member 34 and a third member 36. First member 32 is a printed circuit board; the circuit having a generic flip chip circuit and capacitor by way of example mounted thereon. Circuit board 32 is provided with circuit structure including wiring or trace leads 38 conductively coupled to solder bumps 40 to allow electrical connection with other members 34, 36. Circuit board 32 (interchangeably referred to as first member 32) includes a first plurality of magnets 42 arranged in a pattern 44 to provide a shaped magnetic field. Circuit board 32 also includes a second plurality of magnets 46 arranged in a second pattern 48.
[0038] Second member 34, in this embodiment a flip chip, is formed with a plurality of magnets 50 thereon and solder bumps 52. Magnets 50 are provided in a predetermined pattern 54, which is the mirror image of pattern 44 to provide a mirror shaped magnetic field.
[0039] Similarly, member 36, a capacitor in this example, includes solder bumps 56 and a plurality of magnets 58 in a pattern 60 which is the mirror image of pattern 48. [0040] Magnetic forces arise between the patterns of magnets as a result of the interaction of the magnetic fields between any two magnets. The magnetic fields are related to the material. While all materials have magnetic properties, what are commonly referred to as magnets are typically ferromagnetic in nature and can be classified as either hard or soft magnets. Hard magnetic materials possess a strong permanent magnetization, while soft magnetic materials incur a strong magnetization only upon the application of an external magnetic field. The use of different magnetic materials possessing different magnetic properties and strengths provides flexibility in the design.
[0041] By utilizing complimentary magnetic field patterns, a magnetic "lock and key" matching mechanism is provided. The size, shape, material type, and number of the individual magnets can be used to control the total magnetic patterns of the magnets, resulting in complex magnetic force field interactions, permitting a degree of pattern- matching between the components.
[0042] If sufficiently asymmetric and diverse patterns are generated, it enables orientational uniqueness, bonding selectivity and inter-part bonding. These capabilities are achieved simultaneously in one massively parallel self-assembly step. In an embodiment, agglomeration is prevented because the individual magnets for any given component type are magnetized in the same direction {e.g., all having north or south polarities for the hard magnets). Jn additional embodiments, more complicated magnetic field patterns are utilized with agglomeration prevented as the magnetic attraction between parts of the same type are lower than the mixing force used. Thus, parts of the same type will repel each other, increasing the overall speed of the matching process while preventing misalignment of two bodies.
[0043] Reference is now made to Figs. 4 and 5 for illustrating how the inherent properties of the individual magnets in the array will aid the self-sorting process. As shown in Fig. 4, two uniformly magnetized magnets are separated axially by a gap g and a lateral displacement, d . Under quasi-static conditions, the magnetic force, F , between the two magnets can be computed using several approaches: Maxwell's stress tensor, energetic principles (method of virtual work), or equivalent source models. For all but the simplest geometries, finite-element methods axe typical employed and for finite-element modeling, the method of virtual work has been shown to be the most precise.
[0044] In this approach, the magnetic force is calculated by the derivative of the magnetic energy, U , with respect to a virtual displacement, ds:
Figure imgf000011_0001
The energy is related to the magnetic field distribution B by,
Figure imgf000011_0002
where V is the volume, μ0 is the magnetic permeability of free space. From Eq. (1), it is clear the force acts in a direction so as to reduce the energy stored in the magnetic field. As shown in Fig. 4, the force acts to close the magnetic gap and can be decomposed into an axial pull-in force, Fg , and a radial alignment force, Fd , both functions of the gap, g , and displacement, d .
[0045] Magnetic pattern-matching is possible by combining the interactions of multiple magnets, as depicted in Fig. 5. Here, a plot of potential energy of the system versus lateral displacement, d , exhibits several local minima, as individual magnets align, but only one global minimum, where all the magnets align. Physically, as the arrays shift with respect to each other, overlap of individual magnets may cause small bonding forces. However, the peak bonding force for the system is not reached until all magnets are acting in parallel. This same effect would apply for rotational misalignment, denoted θ , and therefore could be used to realize orientational uniqueness.
[0046] This concept can also be extended to achieve bonding selectivity by considering the potential energy between different magnetic patterns. As dissimilar patterns overlap, individual magnets may cause small bonding forces, the parts will continue to mix until a part with the correct pattern fills the vacancy, thereby minimizing the total free energy. Again, by setting the mixing force higher than any attraction other than that provided by full alignment, the correct orientation will be self-selecting. In an embodiment, if magnets within the pattern are of different polarity, the patterns could cause repulsion between two bodies unless orientation between the patterns was correct so that all magnets attracted all opposed magnets. [0047] Referring back to Fig. 3, during use, a first body such as circuit board 32, is provided with at least one predetermined pattern 44 of a plurality of magnets 42. A desired matching body, such as flip chip 34, is provided with a pattern 54 of a plurality of magnets 50. Magnets 50 are the opposite in polarity of magnets 42, although all of magnets 50 need not be the same polarity. Magnets 50 and/or magnets 42 are hard magnets. However, either one of magnets 50 or 42 may be hard magnets, while the other is a soft magnet. Member 32 and member 34 are mixed with each other. Because of the complementary magnetic patterns, when the magnetic attraction between member 34 and member 32 is sufficient to overcome the mixing forces, member 34, the flip chip, will be affixed to member 32 on the circuit board in the desired orientation so that solder bumps 52 are aligned with solder bumps 40. Because of the need for the magnetic attraction to overcome the mixing force, all non-aligned patterns will be dislodged or repulsed. For this reason, pattern 48 would not sufficiently attract pattern 54 because the overlay of magnets 50 with magnets 46 would not provide sufficient one-to-one correlation to overcome the mixing forces.
[0048] Similarly, second member 36 thrown into the same mixing process would, in parallel, become attracted to circuit board 32 because of the complementary magnetic patterns mirror image magnet patterns 48, 60. In this way, capacitor 36 and flip chip 34 are self-selecting for their appropriate position relative to circuit board 32. The same would be true if circuit board 32 were in fact broken into two pieces so that one half of circuit board 32 would be self-selecting with flip chip 34 while the other half would be self-selecting with capacitor 36 to prevent misfit or disorientation.
[0049] The above examples were described in connection with patterns of a plurality of magnets. However, a patterned magnetic field is needed. Therefore, it is within the scope of the invention to provide a patterned magnetic field from a single magnet having a unique physical shape attracting a second single magnet of mirrored unique physical shape. A third manner to obtain the patterned magnetic field is to provide a single physical magnet with varying magnetic properties (magnetization pattern) within itself in the desired pattern. In various embodiments, various combinations of permanent magnets, soft magnets, magnet arrays, magnet shapes, magnet magnetization profiles, and magnet patterns can be used to achieve a desired magnetic field pattern. [0050] It is preferable for the magnetic materials to be integrated into the component structures. The magnetic structures are relatively small in volume as compared to the bodies in which they reside and therefore large amounts are not required reducing the relative cost. The magnetic processing, as will be described below, can be performed in batch operations. For wafer-level processing, micromagnetic components can be integrated at pattern by electrodeposition as seen in Figs. 6A through 6E.
[0051] In the electrodeposition approach, the micro-magnets are patterned generally through photolithography. A substrate 100 is provided at step 6 A with a deposited seed layer 102. This conductive seed layer 102 is a thin layer of 0.1 μm. In step 6B, small geometric shapes, having a height in the micrometer to millimeter range, are patterned into a photoresist layer 104, serving as the electroplating mold. In a step 6C, magnetic materials 106 are electroplated into the mold formed by photoresist layer 104. In a step 6D, the mold and seed layer 102 are removed by wet etching as known in the art. In step 6E, the wafer is diced as known in the art.
[0052] This process is simple, low cost and CMOS compatible and is efficient for integrating a variety of magnetic materials with sufficient thickness (1 μm to 100 μm +) to provide useful magnetic fields. Many different thick film electroplated permanent magnet materials have been developed for MEMS applications possessing a wide range of magnetic strengths, which would lend themselves to the process.
[0053] Other methods exist in the art for patterning small magnetic patterns onto micro-fabricated parts, such as sputtering. For non-micro-fabricated parts, screen printing particle could be used. Also, new liquid metal jet printing methods, similar to inkjet printing, may be used to deposit small molten droplets of metallic alloys in pattern arrays. Lastly, magnetic materials may be diffused in a pattern into a substrate or body.
[0054] As a result of providing a predetermined magnetic pattern and a complementary magnetic pattern thereof on two respective bodies, it is possible to self- assemble small free floating bodies on a large parallel basis. By providing specific magnet patterns, the bodies will be self-selecting and self-orienting to each other so that only the correct bodies in the correct orientations will bond in a mixing process, whether wet or dry. [0055] In a specific embodiment, the first magnetic field on the first body can be n- fold symmetric and the second magnetic field on the second body can be n-fold symmetric such that there are n orientations that the second body can be fully aligned and bonded with the first body. In other embodiments, the complementary first and second magnetic fields are asymmetric such that only one orientation of the first and second bodies results in full alignment and bonding.
[0056] In a specific embodiment, a structure can have additional bodies that can align and bond to the second body, or any other body of the structure, due to magnetic fields on the additional bodies and the bodies to which the additional bodies align and bond. As an example, a robot structure can have a torso that aligns and bonds with a right arm, a left arm, a right leg, a left leg, and a head. Each of the parts, or bodies, can selectively bond to the torso such that each part bonds only to the appropriate location and not to other locations. In a further embodiment, a right hand, a left hand, a right foot, and a left foot, can align and bond with the right arm, the left arm, the right leg, and the left leg, respectively. The alignment and the bonding can be done in stages or simultaneously. In this way, a plurality of torso and a corresponding plurality of associated parts could be mixed such that the robots are self-assembled. In an analogous way, other structures, such as MEMS structures, could be assembled. Such structures could include a variety of parts to be assembled, such as gears, blocks, levers, and other structures that can be held together via magnets incorporated with the parts.
[0057] hi an embodiment, the first body and second body that will be in contact after alignment and bonding can incorporate other attachment and/or connectivity means, such as glues for mechanical adhesion and solder bumps for electrical connectivity or bonding. In an embodiment, solder bumps can be used such that heating after alignment and bonding can cause a portion of the first body to be soldered to a portion of the second body. In another embodiment, glue can be used such that heating after alignment and bonding can cause a portion of the first body to be glued to a portion of the second body.
[0058] In a specific embodiment, shielding material can be incorporated with the first and/or second body to shield the magnetic fields of the first and/or second body from portions of the aligned and bonded structure or other objects proximate to the structure. Such shielding materials are well known in the art. As an example, soft magnetic materials can be used as shielding. A layer of soft magnetic material can be placed on one or more bodies and then the magnets for the body grown on the soft magnetic material layer such that the portion of the body below the layer is shielded from the magnetic fields of the magnets grown on the layer.
[0059] In a specific embodiment, demagnetizable magnets and/or magnetic materials can be used such that after alignment and bonding, and optional implementation of additional attachment means, the demagnetizable magnets and/or magnetic material can be demagnetized, hi an example, magnets and/or magnetic material that can be demagnetized by heating can be used. Such materials are well known in the art. hi a specific embodiment, magnets and/or magnetic materials that can be demagnetized by heating to demagnetization temperatures under 5000C can be used.
[0060] Preferably, the magnetic attraction force between two bodies are at least as great as the weight force of the body free to move, and at least as great as the weight force of the lightest body if both bodies are free to move. Preferably, the magnetic attraction force is two to ten as great as the weight force of the body free to move, and at least two to ten as great as the weight force of the lightest body if both bodies are free to move.
[0061] Thus, while there have been shown, described and pointed out novel features of the present invention as applied to preferred embodiments thereof, it will be understood that various omissions and substitutions and changes in the form and detail are contemplated so that the disclosed invention may be made by those skilled in the art without departing from the spirit and scope of the invention. It is the intention therefore to be limited only as indicated by the scope of the claims appended hereto. It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention, which as a matter of language might be said to fall therebetween.

Claims

1. A structure adapted for magnetically-directed, self-assembly, comprising: a first body, the first body exhibiting a first magnetic field having a first predetermined pattern; and a second body, the second body exhibiting a second magnetic field having a second predetermined pattern, wherein the first body and the second body are fully aligned to each other and bonded together by a magnetic attraction force between the first body and the second body due to the first and second magnetic fields when the magnetic attraction force between the first body and the second body is sufficient to overcome a mixing force.
2. The structure of claim 1, wherein the first magnetic field is formed by a first at least one permanent magnet disposed on the first body.
3. The structure of claim 2, wherein the first at least one permanent magnet is a first plurality of permanent magnets.
4. The structure of claim 3, wherein at least one permanent magnet of the first plurality of permanent magnets has a different magnetization direction than at least one other permanent magnet of the first plurality of permanent magnets.
5. The structure of claim 3, wherein at least one permanent magnet of the first plurality of permanent magnets has an opposite polarity to at least one other permanent magnet of the first plurality of permanent magnets.
6. The structure of claim 2, wherein the first at least one permanent magnet is a first single permanent magnet with a first complex physical shape.
7. The structure of claim 1, wherein the first magnetic field in n-fold symmetric.
8. The structure of claim 1, wherein the first magnetic field is asymmetric.
9. The structure of claim 1, further comprising: a third body, the third body exhibiting a third magnetic field having a third predetermined pattern, wherein the first body further exhibits a fourth magnetic field having a fourth predetermined pattern, wherein the first body and the third body are fully aligned to each other and bonded together by a magnetic attraction force between the first body and the third body due to the fourth and third magnetic fields when the magnetic attraction force between the first body and the third body is sufficient to overcome the mixing force.
10. The structure of claim 1, further comprising: at least one additional body, the at least one additional body exhibiting a corresponding at least one additional magnetic field having a corresponding at least one additional predetermined pattern, wherein the first body further exhibits a corresponding at least one additional magnetic field having a corresponding at least one predetermined pattern, wherein the first body and each of the at least one additional body are fully aligned to each other and bonded together by a magnetic attraction force between the first body and the at least one additional body due to the corresponding at least one magnetic fields of the first body and the at least one additional body when the magnetic attraction force between the first body and the at least one additional body due to the corresponding at least one magnetic fields of the first body and the at least one additional body is sufficient to overcome the mixing force.
11. The structure of claim 1, wherein the mixing force is higher than any magnetic attraction force between the first body and the second body other than that provided by full alignment of the first body and the second body.
12. The structure of claim 11, wherein the mixing force is higher than magnetic attraction forces for local minima of potential energy versus lateral and/or rotational misalignment of the first body and the second body from full alignment.
13. The structure of claim 2, wherein the second magnetic field is formed by a second at least one permanent magnet disposed on the second body.
14. The structure of claim 2, wherein the second magnetic field is formed by at least one soft magnet disposed on the second body, wherein the second magnetic field is exhibited when the at least one soft magnet is magnetized by the first magnetic field.
15. The structure of claim 2, wherein at least one of the first at least one permanent magnet has varying magnet properties.
16. The structure of claim 2, wherein the second magnetic field is formed by a second single permanent magnet with a second complex physical shape disposed on the second body.
17. The structure of claim 16, wherein the second complex physical shape is the mirror image of the first complex physical shape.
18. The structure of claim 2, wherein the second magnetic field is formed by a single j soft magnet with a second complex physical shape disposed on the second body, wherein the second magnetic field is exhibited when the at least one soft magnet is magnetized by the first magnetic field.
19. The structure of claim 18, wherein the second complex physical shape is the mirror-image of the first complex physical shape.
20. The structure of claim 1, wherein the second predetermined pattern is complementary to the first predetermined pattern.
21. The structure of claim 9, wherein the mixing force is higher than any magnetic attraction force between the first body and the third body other than that provided by full alignment of the first body and the third body.
22. The structure of claim 21, wherein the mixing force is higher than local minima of potential energy versus lateral and/or rotational misalignment of the first body and the third body.
23. The structure according to claim 1, further comprising: a means for attaching the first body to the second body after the first body and the second body are bonded together.
24. The structure of claim 1, wherein the first body comprises first circuitry thereon and the second body comprises second circuitry thereon, the second circuitry being operatively oriented to the first circuitry when the first body and second body are fully aligned to each other and bonded together.
25. The structure of claim 24, wherein a means to electrically connect the first circuitry to the second circuitry after the first body and the second body are bonded together.
26. The structure of claim 25, wherein the means to electrically connect the first circuitry and the second circuitry comprises solder bumps.
27. The structure of claim 9, wherein the first body exhibits the first magnetic field at a first portion of the first body and the first body exhibits the fourth magnetic field having a fourth predetermined pattern at a second portion of the first body, wherein the first body is capable of selectively bonding with the second body at the first portion of the first body and selectively bonding with the third body at the second portion of the first body, such the mixing force is higher than any magnetic attraction force between the first portion of the first body and the third body, and the mixing force is higher than any magnetic attraction force between the second portion of the first body and the second body, wherein the mixing force is higher than any magnetic attraction force between the second body and the third body.
28. The structure of claim 13, wherein the second at least one permanent magnet forms a second pattern of magnets that is a mirror image of a first pattern of magnets formed by the first at least one permanent magnet.
29. The structure of claim 14, wherein the at least one soft magnet forms a second pattern of magnets that is a mirror image of a first pattern of magnets formed by the first at least one permanent magnet.
30. The structure of claim 1, wherein the mixing force is higher than any magnetic attraction force between the second body and another second body.
31. A method for magnetically-directed self-assembling parts, comprising: providing at least one first body, each first body exhibiting a first magnetic field having a first predetermined pattern; providing at least one second body, each second body exhibiting a second magnetic field having a second predetermined pattern; mixing the at least one first body with the at least one second body with a mixing force, wherein one of the at least one first body and one of the at least one second body are fully aligned to each other and bonded together by a magnetic attraction force between the one of the at least one first body and the one of the at least one second body when a magnetic attraction force between the one of the least one first body and the one of the at least one second body is sufficient to overcome the mixing force.
32. The method of claim 31, wherein the mixing force is higher than any magnetic attraction force other than that provided by full alignment of one of the at least one first body and one of the at least one second body.
33. The method of claim 32, wherein the mixing force is higher than local minima of potential energy versus lateral and/or rotational misalignment of one of the at least one first body and one of the at least one second body.
34. The method of claim 31, wherein the first magnetic field is formed by a first at least one permanent magnet disposed on each first body.
35. The method of claim 34, wherein the first at least one permanent magnet comprises a first single permanent magnet with a first complex physical shape.
36. The method of claim 31, wherein the first magnetic field is n-fold symmetric.
37. The method of claim 31, wherein the first magnetic field is asymmetric.
38. The method of claim 34, wherein the first at least one permanent magnet comprises a first plurality of permanent magnets.
39. The method of claim 38, wherein at least one of the permanent magnets of the first plurality of permanent magnets has a different magnetization direction than at least one other permanent magnet of the first plurality of permanent magnets.
40. The method of claim 34, wherein the second magnetic field is formed by a second at least one permanent magnet disposed on each second body.
41. The method of claim 34, wherein the second magnetic field is formed by a second at least one soft magnet disposed on each second body, wherein the second magnetic field is exhibited when the at least one soft magnet is magnetized by the first magnetic field.
42. The method of claim 34, wherein the second magnetic field is formed by a second single permanent magnet with a complex physical shape disposed on each second body.
43. The method of claim 34, wherein the second magnetic field is formed by a single soft magnet with a complex physical shape disposed on each second body.
44. The method of claim 42, wherein the second predetermined pattern is complementary to the first predetermined pattern.
45. The method of claim 43, wherein the second predetermined pattern is complementary to the first predetermined pattern.
46. The structure of claim 1, further comprising: shielding, wherein the shielding shields at least a portion of the first magnetic field or the second magnetic field from at least a portion of the first body or the second body when the first body and the second body are bonded together.
47. The structure of claim 1, where the magnetic attraction force between the first body and the second body is at least two times the weight force of the lighter of the first body and the second body.
48. The structure of claim 2, wherein the at least one permanent magnet is demagnetizable .
49. The method according to claim 31, further comprising: providing at least one third body, each third body exhibiting a third magnetic field having a third predetermined pattern, wherein each first body further exhibits a fourth magnetic field having a fourth predetermined pattern, wherein one of the at least one first body and one of the at least one third body are fully aligned to each other and bonded together by a magnetic attraction force between the one of the at least one first body and the one of the at least one third body due to the fourth and third magnetic fields when the magnetic attraction force between the one of the at least one first body and the one of the at least one third body is sufficient to overcome the mixing force.
50. The method according to claim 49, wherein each first body exhibits the first magnetic field at a first portion of each first body and each first body exhibits the fourth magnetic field having a fourth predetermined pattern at a second portion of each first body, wherein each first body is capable of selectively bonding with each second body at the first portion of each first body and selectively bonding with each third body at the second portion of each first body, such that the mixing force is higher than any magnetic attraction force between the first portion of each first body and each third body, and the mixing force is higher than any magnetic attraction force between the second portion of each first body and each second body, wherein the mixing force is higher than any magnetic attraction force between each second body and each third body.
51. The method according to claim 50, wherein the mixing force is higher than local minima of potential energy versus lateral and/or rotational misalignment of each first body and each third body.
52. The method according to claim 50, wherein each first body comprises first circuitry thereon and each second body comprises second circuitry thereon, the second circuitry being operatively oriented to the first circuitry when one of the at least one first body and one of the at least one second body are fully aligned to each other and bonded together.
53. The method according to claim 52, further comprising electrically connecting the first circuitry to the second circuitry after the first body and the second body are bonded together.
54. The method according to claim 53, electrically connecting the first circuitry and the second circuitry comprises electrically connecting the first circuitry and the second circuitry via solder bumps.
55. The method according to claim 40, wherein the second at least one permanent magnet forms a second pattern of magnets that is a mirror image of a first pattern of magnets formed by the first at least one permanent magnet.
56. The method according to claim 41, wherein the at least one soft magnet forms a second pattern of magnets that is a mirror image of a first pattern of magnets formed by the first at least one permanent magnet.
57. The method according to claim 31, wherein the mixing force is higher than any magnetic attraction force between two of the at least one second body.
58. The method according to claim 31, further comprising: shielding at least a portion of the first magnetic field or the second magnetic field from at least a portion of the first body or the second body when the first body and the second body are bonded together.
59. The method according to claim 31, where the magnetic attraction force between each first body and each second body is at least two times the weight force of the lighter of the first body and the second body.
60. The method according to claim 32, wherein the at least one permanent magnet is demagnetizable.
61. The method according to claim 49, wherein the mixing force is higher than any magnetic attraction force between each first body and each third body other than that provided by full alignment of one of the at least one first body and one of the at least one third body.
PCT/US2006/045633 2005-11-28 2006-11-28 Method and structure for magnetically-directed, self-assembly of three-dimensional structures WO2007062268A2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US12/102,758 US8138868B2 (en) 2005-11-28 2008-04-14 Method and structure for magnetically-directed, self-assembly of three-dimensional structures

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US74013905P 2005-11-28 2005-11-28
US60/740,139 2005-11-28

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US12/102,758 Continuation-In-Part US8138868B2 (en) 2005-11-28 2008-04-14 Method and structure for magnetically-directed, self-assembly of three-dimensional structures

Publications (3)

Publication Number Publication Date
WO2007062268A2 true WO2007062268A2 (en) 2007-05-31
WO2007062268A3 WO2007062268A3 (en) 2007-08-09
WO2007062268A8 WO2007062268A8 (en) 2007-10-11

Family

ID=38067990

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2006/045633 WO2007062268A2 (en) 2005-11-28 2006-11-28 Method and structure for magnetically-directed, self-assembly of three-dimensional structures

Country Status (2)

Country Link
US (1) US8138868B2 (en)
WO (1) WO2007062268A2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107072069A (en) * 2017-05-27 2017-08-18 潍坊路加精工有限公司 Pin welds correcting device

Families Citing this family (82)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI471971B (en) * 2007-10-30 2015-02-01 尼康股份有限公司 Substrate holding member, substrate bonding apparatus, laminated substrate manufacturing apparatus, substrate bonding method, laminated substrate manufacturing method, and laminated semiconductor device manufacturing method
US7800471B2 (en) 2008-04-04 2010-09-21 Cedar Ridge Research, Llc Field emission system and method
US8373527B2 (en) 2008-04-04 2013-02-12 Correlated Magnetics Research, Llc Magnetic attachment system
US8816805B2 (en) 2008-04-04 2014-08-26 Correlated Magnetics Research, Llc. Magnetic structure production
US8779879B2 (en) 2008-04-04 2014-07-15 Correlated Magnetics Research LLC System and method for positioning a multi-pole magnetic structure
US8576036B2 (en) 2010-12-10 2013-11-05 Correlated Magnetics Research, Llc System and method for affecting flux of multi-pole magnetic structures
US8760250B2 (en) 2009-06-02 2014-06-24 Correlated Magnetics Rsearch, LLC. System and method for energy generation
US8174347B2 (en) 2010-07-12 2012-05-08 Correlated Magnetics Research, Llc Multilevel correlated magnetic system and method for using the same
US9105380B2 (en) 2008-04-04 2015-08-11 Correlated Magnetics Research, Llc. Magnetic attachment system
US8368495B2 (en) 2008-04-04 2013-02-05 Correlated Magnetics Research LLC System and method for defining magnetic structures
US9202616B2 (en) 2009-06-02 2015-12-01 Correlated Magnetics Research, Llc Intelligent magnetic system
US8760251B2 (en) 2010-09-27 2014-06-24 Correlated Magnetics Research, Llc System and method for producing stacked field emission structures
US9371923B2 (en) 2008-04-04 2016-06-21 Correlated Magnetics Research, Llc Magnetic valve assembly
US8279032B1 (en) 2011-03-24 2012-10-02 Correlated Magnetics Research, Llc. System for detachment of correlated magnetic structures
US8179219B2 (en) 2008-04-04 2012-05-15 Correlated Magnetics Research, Llc Field emission system and method
US8917154B2 (en) 2012-12-10 2014-12-23 Correlated Magnetics Research, Llc. System for concentrating magnetic flux
US8937521B2 (en) 2012-12-10 2015-01-20 Correlated Magnetics Research, Llc. System for concentrating magnetic flux of a multi-pole magnetic structure
US20140033482A1 (en) * 2012-08-06 2014-02-06 Correlated Magnetics Research, Llc Magnetic attachment system having a multi-pole magnetic structure and pole pieces
US9275783B2 (en) 2012-10-15 2016-03-01 Correlated Magnetics Research, Llc. System and method for demagnetization of a magnetic structure region
US9404776B2 (en) 2009-06-02 2016-08-02 Correlated Magnetics Research, Llc. System and method for tailoring polarity transitions of magnetic structures
US9257219B2 (en) 2012-08-06 2016-02-09 Correlated Magnetics Research, Llc. System and method for magnetization
US8704626B2 (en) 2010-05-10 2014-04-22 Correlated Magnetics Research, Llc System and method for moving an object
FR2948603B1 (en) * 2009-07-29 2013-03-08 Sgd Sa SYSTEM FOR APPLYING A PATTERN TO A SUBSTRATE AND CORRESPONDING METHOD
US9711268B2 (en) 2009-09-22 2017-07-18 Correlated Magnetics Research, Llc System and method for tailoring magnetic forces
US20110115588A1 (en) * 2009-11-17 2011-05-19 Digirad Corporation Magnetic Attachment of Detector Modules enabling front side removal
US8586410B2 (en) * 2010-01-25 2013-11-19 University Of Florida Research Foundation, Inc. Enhanced magnetic self-assembly using integrated micromagnets
US9446950B2 (en) 2010-01-29 2016-09-20 Paul Michael Chaikin Method and system using microscopic building blocks for driving 3D self-assembly
WO2011163618A2 (en) * 2010-06-24 2011-12-29 The Johns Hopkins University Array structures of containers
CN102971873B (en) * 2010-07-14 2016-10-26 夏普株式会社 The collocation method of small items, collating unit, illuminator and display device
US8638016B2 (en) 2010-09-17 2014-01-28 Correlated Magnetics Research, Llc Electromagnetic structure having a core element that extends magnetic coupling around opposing surfaces of a circular magnetic structure
TWI434122B (en) * 2011-01-21 2014-04-11 Delta Electronics Inc A magnetic fix structure apply on a projection device
TW201237740A (en) * 2011-03-15 2012-09-16 Acer Inc Compound electrical devices and methods for displaying image data
US8702437B2 (en) 2011-03-24 2014-04-22 Correlated Magnetics Research, Llc Electrical adapter system
US9330825B2 (en) 2011-04-12 2016-05-03 Mohammad Sarai Magnetic configurations
US8963380B2 (en) 2011-07-11 2015-02-24 Correlated Magnetics Research LLC. System and method for power generation system
US9219403B2 (en) 2011-09-06 2015-12-22 Correlated Magnetics Research, Llc Magnetic shear force transfer device
US8848973B2 (en) 2011-09-22 2014-09-30 Correlated Magnetics Research LLC System and method for authenticating an optical pattern
US20130199831A1 (en) * 2012-02-06 2013-08-08 Christopher Morris Electromagnetic field assisted self-assembly with formation of electrical contacts
WO2013130667A2 (en) 2012-02-28 2013-09-06 Correlated Magnetics Research, Llc. System for detaching a magnetic structure from a ferromagnetic material
EP2677291B1 (en) * 2012-06-19 2017-09-20 Technische Universität München Capacitive force sensor and fabrication method
US9245677B2 (en) 2012-08-06 2016-01-26 Correlated Magnetics Research, Llc. System for concentrating and controlling magnetic flux of a multi-pole magnetic structure
US9007157B2 (en) * 2012-08-28 2015-04-14 Apple Inc. Magnetic assembly
US20140079266A1 (en) * 2012-09-14 2014-03-20 Research In Motion Limited Mating portable speaker with protected connector
US9298281B2 (en) 2012-12-27 2016-03-29 Correlated Magnetics Research, Llc. Magnetic vector sensor positioning and communications system
KR102136844B1 (en) 2013-09-30 2020-07-22 삼성전자 주식회사 Wafer processing method and method for fabricating semiconductor device using the same processing method
KR20150054502A (en) * 2013-11-12 2015-05-20 삼성전자주식회사 Semiconductor device having magnetic substanceand related equipment
US10242977B2 (en) 2014-10-31 2019-03-26 eLux, Inc. Fluid-suspended microcomponent harvest, distribution, and reclamation
US10319878B2 (en) 2014-10-31 2019-06-11 eLux, Inc. Stratified quantum dot phosphor structure
US10516084B2 (en) 2014-10-31 2019-12-24 eLux, Inc. Encapsulated fluid assembly emissive elements
US10134517B2 (en) * 2015-03-02 2018-11-20 1Lss, Inc. Self-aligning, multi-surface magnetic mount for electronic display devices
DE102015212801A1 (en) 2015-07-08 2017-01-12 Te Connectivity Germany Gmbh Electrical switching arrangement with improved linear storage
KR101714733B1 (en) * 2015-08-13 2017-03-09 한국기계연구원 Detachable device for loading unit of robot, robot and controlling method of robot using the same
US10605774B2 (en) * 2015-09-17 2020-03-31 Apple Inc. Magnetic imaging
US9711443B2 (en) * 2015-11-14 2017-07-18 Intel Corporation Magnetic alignment for flip chip microelectronic devices
WO2018043686A1 (en) * 2016-08-31 2018-03-08 京セラ株式会社 Sensor device and detecting method employing same
US10987804B2 (en) * 2016-10-19 2021-04-27 Fuji Xerox Co., Ltd. Robot device and non-transitory computer readable medium
US10265844B2 (en) * 2017-03-24 2019-04-23 International Business Machines Corporation Creating assembly plans based on triggering events
CN107321744B (en) * 2017-06-05 2022-11-15 东莞创群石英晶体有限公司 Quick magnet dismounting device for bottom frame of quartz crystal wafer and using method thereof
US10622270B2 (en) 2017-08-31 2020-04-14 Texas Instruments Incorporated Integrated circuit package with stress directing material
US10553573B2 (en) 2017-09-01 2020-02-04 Texas Instruments Incorporated Self-assembly of semiconductor die onto a leadframe using magnetic fields
CN107644827B (en) * 2017-10-20 2019-09-10 常州工学院 A kind of microfluid excitation micro element self-assembly device and method
US10833648B2 (en) 2017-10-24 2020-11-10 Texas Instruments Incorporated Acoustic management in integrated circuit using phononic bandgap structure
US10886187B2 (en) 2017-10-24 2021-01-05 Texas Instruments Incorporated Thermal management in integrated circuit using phononic bandgap structure
US10497651B2 (en) 2017-10-31 2019-12-03 Texas Instruments Incorporated Electromagnetic interference shield within integrated circuit encapsulation using photonic bandgap structure
US10444432B2 (en) 2017-10-31 2019-10-15 Texas Instruments Incorporated Galvanic signal path isolation in an encapsulated package using a photonic structure
US10371891B2 (en) 2017-10-31 2019-08-06 Texas Instruments Incorporated Integrated circuit with dielectric waveguide connector using photonic bandgap structure
US10557754B2 (en) 2017-10-31 2020-02-11 Texas Instruments Incorporated Spectrometry in integrated circuit using a photonic bandgap structure
US10555427B2 (en) * 2017-11-08 2020-02-04 Microsoft Technology Licensing, Llc Electronic device with a magnetically attached electronic component
US10607515B2 (en) * 2018-04-19 2020-03-31 Lg Electronics Inc. Display device using semiconductor light emitting device and method for manufacturing the same
CN108682312B (en) * 2018-05-12 2020-11-06 汕头超声显示器技术有限公司 Manufacturing method of LED array device
CN111129245B (en) * 2018-10-31 2022-09-06 成都辰显光电有限公司 LED chip, display panel and display panel's equipment
CN110265424B (en) * 2019-06-25 2022-06-10 京东方科技集团股份有限公司 Display panel, manufacturing method thereof and mother board
KR102173349B1 (en) * 2019-06-28 2020-11-03 엘지전자 주식회사 Substrate for manufacturing display device and method for manufacturing display device
KR102173350B1 (en) * 2019-06-28 2020-11-03 엘지전자 주식회사 Method for manufacturing display device and substrate for manufacturing display device
DE102019210177B4 (en) 2019-07-10 2021-05-20 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. Process for the production of an oppositely magnetized magnetic structure
WO2021054508A1 (en) 2019-09-19 2021-03-25 엘지전자 주식회사 Self-assembly apparatus for semiconductor light-emitting elements
WO2021054548A1 (en) 2019-09-19 2021-03-25 Lg Electronics Inc. Substrate chuck for self-assembling semiconductor light-emitting diodes
WO2021054550A1 (en) * 2019-09-19 2021-03-25 Lg Electronics Inc. Device for self-assembling semiconductor light-emitting diodes
EP4071789A4 (en) 2019-09-19 2024-02-14 Lg Electronics Inc Substrate chuck for self-assembly of semiconductor light-emitting diodes
KR102323256B1 (en) * 2019-09-19 2021-11-08 엘지전자 주식회사 Self assembly device for semiconductor light emitting device
WO2021054507A1 (en) 2019-09-19 2021-03-25 엘지전자 주식회사 Self-assembly apparatus for semiconductor light-emitting elements
KR20210072194A (en) 2019-12-06 2021-06-17 삼성디스플레이 주식회사 Method for aligning a light emitting element, method for fabricating a display device using the same and display device

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3228133A (en) * 1965-03-02 1966-01-11 Baermann Max Permanent magnet display board
US3439416A (en) * 1966-02-03 1969-04-22 Gen Telephone & Elect Method and apparatus for fabricating an array of discrete elements
US20030234401A1 (en) * 2002-01-24 2003-12-25 Fonstad Clifton G. Method and system for magnetically assisted statistical assembly of wafers
WO2005089184A2 (en) * 2004-03-12 2005-09-29 New Jersey Institute Of Technology Method of magnetic field assisted self-assembly

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4227848B4 (en) * 1991-11-28 2009-05-07 Robert Bosch Gmbh Component carrier and method for holding a formed of a ferromagnetic material component
US5355577A (en) * 1992-06-23 1994-10-18 Cohn Michael B Method and apparatus for the assembly of microfabricated devices
US5596304A (en) * 1994-03-29 1997-01-21 The Board Of Trustees Of The Leland Stanford Junior University Permanent magnet edge-field quadrupole
KR100862131B1 (en) * 2000-08-22 2008-10-09 프레지던트 앤드 펠로우즈 오브 하버드 칼리지 Semiconductor nanowires manufacturing method
US6780696B1 (en) * 2000-09-12 2004-08-24 Alien Technology Corporation Method and apparatus for self-assembly of functional blocks on a substrate facilitated by electrode pairs
US6653919B2 (en) * 2001-02-02 2003-11-25 Wistron Corp Magnetic closure apparatus for portable computers
TW507979U (en) * 2001-04-04 2002-10-21 Benq Corp magnetic hinge apparatus
FR2844158B1 (en) * 2002-09-06 2004-11-05 Techpack Int PACKAGING, TYPICALLY A CASE, WITH MAGNET CLOSURE
US6929291B2 (en) * 2003-07-28 2005-08-16 Inventec Corp. Magnetic lock
US7251882B2 (en) * 2004-09-03 2007-08-07 Eastman Kodak Company Method for assembling micro-components to binding sites
US7629026B2 (en) * 2004-09-03 2009-12-08 Eastman Kodak Company Thermally controlled fluidic self-assembly
US7804966B2 (en) * 2004-12-20 2010-09-28 Fender Musical Instruments Corporation Audio amplifier attachable to speaker system by way of magnetic coupler and method therefor
US7615836B2 (en) 2005-03-07 2009-11-10 Sensormatic Electronics Corporation Magnetic self-assembly for integrated circuit packages
US7671712B2 (en) * 2005-03-25 2010-03-02 Ellihay Corp Levitation of objects using magnetic force
US7644489B2 (en) * 2005-08-31 2010-01-12 Massachusetts Institute Of Technology Thin membrane alignment method using patterned nanomagnets
TWI285305B (en) * 2005-11-07 2007-08-11 High Tech Comp Corp Auto-aligning and connecting structure between electronic device and accessory

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3228133A (en) * 1965-03-02 1966-01-11 Baermann Max Permanent magnet display board
US3439416A (en) * 1966-02-03 1969-04-22 Gen Telephone & Elect Method and apparatus for fabricating an array of discrete elements
US20030234401A1 (en) * 2002-01-24 2003-12-25 Fonstad Clifton G. Method and system for magnetically assisted statistical assembly of wafers
WO2005089184A2 (en) * 2004-03-12 2005-09-29 New Jersey Institute Of Technology Method of magnetic field assisted self-assembly

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107072069A (en) * 2017-05-27 2017-08-18 潍坊路加精工有限公司 Pin welds correcting device

Also Published As

Publication number Publication date
WO2007062268A8 (en) 2007-10-11
US20080218299A1 (en) 2008-09-11
US8138868B2 (en) 2012-03-20
WO2007062268A3 (en) 2007-08-09

Similar Documents

Publication Publication Date Title
WO2007062268A2 (en) Method and structure for magnetically-directed, self-assembly of three-dimensional structures
US8586410B2 (en) Enhanced magnetic self-assembly using integrated micromagnets
US6687987B2 (en) Electro-fluidic assembly process for integration of electronic devices onto a substrate
US8082660B2 (en) Xerographic micro-assembler
Cohn et al. Microassembly technologies for MEMS
US7217592B2 (en) Method of magnetic field assisted self-assembly
US20100170086A1 (en) Device, unit, system and method for the magnetically-assisted assembling of chip-scale, and nano and micro-scale components onto a substrate
JP3817815B2 (en) Electromagnetic connector
WO2003063570A2 (en) A method and system for magnetically assisted statistical assembly of wafers
US6049974A (en) Magnetic alignment apparatus and method for self-alignment between a die and a substrate
Shetye et al. Self-assembly of millimeter-scale components using integrated micromagnets
Shetye et al. Magnetic self-assembly of millimeter-scale components with angular orientation
Tkachenko et al. Directed self-assembly of mesoscopic electronic components into sparse arrays with controlled orientation using diamagnetic levitation
US20060022784A1 (en) Microtechnological device comprising magnetically assembled structures and assembly process
Kuran et al. Integration of laser die transfer and magnetic self-assembly for ultra-thin chip placement
Kuran et al. Magnetic self-assembly of ultra-thin chips to polymer foils
Park et al. Optimization of angular alignment in self-assembly of thin parts at an air–water interface
Fang et al. Self-assembly of flat micro components by capillary forces and shape recognition
Shet et al. Microassembly techniques: A review
Shetye Magnetic self-assembly of small parts
Tkachenko et al. Directed self-assembly of mesoscopic dies using magnetic force and shape recognition
Fang Self-assembly techniques for massively parallel packaging of MEMS devices
JP2007514555A (en) Method and system for self-aligning parts of a MEMS
Kasisomayajula et al. Magnetic field assisted heterogeneous device assembly
Kuran et al. Magnetic force driven self-assembly of ultra-thin chips

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 06838540

Country of ref document: EP

Kind code of ref document: A2