CA2000449C - Diode laser soldering system - Google Patents

Diode laser soldering system

Info

Publication number
CA2000449C
CA2000449C CA002000449A CA2000449A CA2000449C CA 2000449 C CA2000449 C CA 2000449C CA 002000449 A CA002000449 A CA 002000449A CA 2000449 A CA2000449 A CA 2000449A CA 2000449 C CA2000449 C CA 2000449C
Authority
CA
Canada
Prior art keywords
lead
laser
laser light
fiber optic
circuit board
Prior art date
Legal status (The legal status 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 status listed.)
Expired - Fee Related
Application number
CA002000449A
Other languages
French (fr)
Other versions
CA2000449A1 (en
Inventor
Joseph R. Adamski
Christopher Ferguson
William E. Prifti
William E. Nothe
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Raytheon Co
Original Assignee
Raytheon Co
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 Raytheon Co filed Critical Raytheon Co
Publication of CA2000449A1 publication Critical patent/CA2000449A1/en
Application granted granted Critical
Publication of CA2000449C publication Critical patent/CA2000449C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C66/00General aspects of processes or apparatus for joining preformed parts
    • B29C66/80General aspects of machine operations or constructions and parts thereof
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K1/00Soldering, e.g. brazing, or unsoldering
    • B23K1/005Soldering by means of radiant energy
    • B23K1/0056Soldering by means of radiant energy soldering by means of beams, e.g. lasers, E.B.
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00Working by laser beam, e.g. welding, cutting or boring
    • B23K26/02Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
    • B23K26/06Shaping the laser beam, e.g. by masks or multi-focusing
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00Working by laser beam, e.g. welding, cutting or boring
    • B23K26/02Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
    • B23K26/06Shaping the laser beam, e.g. by masks or multi-focusing
    • B23K26/0604Shaping the laser beam, e.g. by masks or multi-focusing by a combination of beams
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00Working by laser beam, e.g. welding, cutting or boring
    • B23K26/02Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
    • B23K26/06Shaping the laser beam, e.g. by masks or multi-focusing
    • B23K26/0604Shaping the laser beam, e.g. by masks or multi-focusing by a combination of beams
    • B23K26/0613Shaping the laser beam, e.g. by masks or multi-focusing by a combination of beams having a common axis
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00Working by laser beam, e.g. welding, cutting or boring
    • B23K26/02Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
    • B23K26/06Shaping the laser beam, e.g. by masks or multi-focusing
    • B23K26/064Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00Working by laser beam, e.g. welding, cutting or boring
    • B23K26/02Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
    • B23K26/06Shaping the laser beam, e.g. by masks or multi-focusing
    • B23K26/064Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms
    • B23K26/0648Shaping the laser beam, e.g. by masks or multi-focusing by means of optical elements, e.g. lenses, mirrors or prisms comprising lenses
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23KSOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00Working by laser beam, e.g. welding, cutting or boring
    • B23K26/02Positioning or observing the workpiece, e.g. with respect to the point of impact; Aligning, aiming or focusing the laser beam
    • B23K26/06Shaping the laser beam, e.g. by masks or multi-focusing
    • B23K26/0665Shaping the laser beam, e.g. by masks or multi-focusing by beam condensation on the workpiece, e.g. for focusing
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C65/00Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
    • B29C65/02Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
    • B29C65/14Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using wave energy, i.e. electromagnetic radiation, or particle radiation
    • B29C65/16Laser beams
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C65/00Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
    • B29C65/02Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
    • B29C65/44Joining a heated non plastics element to a plastics element
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C66/00General aspects of processes or apparatus for joining preformed parts
    • B29C66/70General aspects of processes or apparatus for joining preformed parts characterised by the composition, physical properties or the structure of the material of the parts to be joined; Joining with non-plastics material
    • B29C66/74Joining plastics material to non-plastics material
    • B29C66/742Joining plastics material to non-plastics material to metals or their alloys
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C66/00General aspects of processes or apparatus for joining preformed parts
    • B29C66/80General aspects of machine operations or constructions and parts thereof
    • B29C66/84Specific machine types or machines suitable for specific applications
    • B29C66/843Machines for making separate joints at the same time in different planes; Machines for making separate joints at the same time mounted in parallel or in series
    • B29C66/8432Machines for making separate joints at the same time mounted in parallel or in series
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01RELECTRICALLY-CONDUCTIVE CONNECTIONS; STRUCTURAL ASSOCIATIONS OF A PLURALITY OF MUTUALLY-INSULATED ELECTRICAL CONNECTING ELEMENTS; COUPLING DEVICES; CURRENT COLLECTORS
    • H01R43/00Apparatus or processes specially adapted for manufacturing, assembling, maintaining, or repairing of line connectors or current collectors or for joining electric conductors
    • H01R43/02Apparatus or processes specially adapted for manufacturing, assembling, maintaining, or repairing of line connectors or current collectors or for joining electric conductors for soldered or welded connections
    • H01R43/0221Laser welding
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C65/00Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
    • B29C65/02Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
    • B29C65/14Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure using wave energy, i.e. electromagnetic radiation, or particle radiation
    • B29C65/16Laser beams
    • B29C65/1603Laser beams characterised by the type of electromagnetic radiation
    • B29C65/1612Infrared [IR] radiation, e.g. by infrared lasers
    • B29C65/1616Near infrared radiation [NIR], e.g. by YAG lasers
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B29WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29CSHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C66/00General aspects of processes or apparatus for joining preformed parts
    • B29C66/01General aspects dealing with the joint area or with the area to be joined
    • B29C66/05Particular design of joint configurations
    • B29C66/20Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines
    • B29C66/21Particular design of joint configurations particular design of the joint lines, e.g. of the weld lines said joint lines being formed by a single dot or dash or by several dots or dashes, i.e. spot joining or spot welding
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00Apparatus or processes for manufacturing printed circuits
    • H05K3/30Assembling printed circuits with electric components, e.g. with resistor
    • H05K3/32Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits
    • H05K3/34Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits by soldering
    • H05K3/341Surface mounted components
    • H05K3/3421Leaded components
    • HELECTRICITY
    • H05ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
    • H05KPRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
    • H05K3/00Apparatus or processes for manufacturing printed circuits
    • H05K3/30Assembling printed circuits with electric components, e.g. with resistor
    • H05K3/32Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits
    • H05K3/34Assembling printed circuits with electric components, e.g. with resistor electrically connecting electric components or wires to printed circuits by soldering
    • H05K3/3494Heating methods for reflowing of solder

Abstract

A laser soldering system wherein a plurality of laser beams are simultaneously directed to a plurality of spatially separate locations on a printed circuit board for simultaneously soldering. Each of the laser beams is formed by combining the outputs of a plurality of fiber cables, each of which is connected to an individual laser diode.

Description

Zli~ 9 DIODE LASF:R ~;OLDERI~JG SYSTEr~l Backqround of the Invention The ~ield of the invention generally relates to diode laser soldering systems that combine laser liqht from a plurality of laser sources to qenerate a higher intensity laser beam to melt materials that are used to connect inte-qrated circuit packages to a Printed circuit boarA. More particularly, this invention relates to a diode laser soldering system that can simultaneously melt solder at different locations on a Printed circuit board.
As is known in the electronics industry, electronic circuits are formed by placing integrated circuits (IC's) on printed circuit boards. During manu~acture, the IC packa~es are inserted onto the printed circuit board, with the leads extending through eyelets in the board. Next, the board is passed thouqh a wave solde~ machine that applies a thin laver of molten solder to the lead projection regions on the bottom of the printed circuit board.
With the advent of surface mount ComPonents, IC packaaes are mounted on both sides of a circuit board. With such arranqement, a wave solder ~achine may not be practical to use because the wave solder machine could damaqe comPonents.
One ~ethod surface mount IC's are beinq soldered to the printed circuit boards is by hand. A printed circuit hoard that is to hold surface mount components is constructed with solder attached to the location where the IC lead is to be placed. The integrated circuit packages are then attached to the printed circuit board. A technician then applies heat to the lead of the IC component with a soldering iron. The soldering iron then causes the lead to heat up and melt the pre-deposited solder onto the IC leads~ Hand construction of surface mount components has drawbacks, as the technician may apply heat to the lead too long, which can cause daMage to the inteyrated circuit. Further, the technician may not apply the soldering iron to the integrated circuit le~d long enough, which results in a cold solder joint and an unreliable connection. Another drawback to using the soldering iron is that the operator may apply the solder iron to the wrong location on the printed circui~ boardJ thereby damaging the board.
Another method of soldering surface mount components to a printed circuit board is by using a laser system. Current laser systems use a mirror and a glass lens to focus a beam of a YAG laser onto the IC lead loeation on the printed circuit board where the solder is to be melted. The laser is applied to that point for a period of 0.5 to ~00 seconds to heat the IC lead, resulting in the IC component being soldered to the board. When another location is to be soldered, the mirror rotates slightly, which directs the laser beam to another location. One drawback to this system is that the .:

.

' 2~J~

laser only solders one or two locations at a time (see U.S.
Patent No. 4,327,277), resulting in a lengthy amount of time to solder a complete printed circuit board. An addi-tional drawback of the YAG laser is that it is expensive to construct. Another drawback of the YAG laser system is that the laser's associated reflecting and focusing glass requires a great deal of space, thereby preventing a multi-plicity of laser sources.
Laser diodes have been used for generating lasers light;
however, a laser diode radiates a single beam having a small amount of laser light, thereby making it difficult to use laser diodes when heating materials. Further, individual laser diodes are too large to allow a multiplicity of diodes to join together to combine their light. Accordingly, 15- laser diodes have not been used to melt solder.

. , , , , ,~ . . . ~ , 2'~ 9 Summary of the Invention It is an object of this invention to provide an improved soldering system.
It is another object of this invention to provide an apparatus that combines light from a plurality of sources and maintains the original intensity of the light.
It is a object of this invention to provide a soldering system that simultaneously melts different points on a printed circuit board at the same time.
It is also an object of this invention to provide an improved apparatus for soldering components to surface mount printed circuit board.
These and other objects of the invention are obtained genérally by providing an apparatus for directing laser light at an electronic circuit, where the apparatus comprises means for generating a plurality of laser light beams and means optically coupled to the generating means for combining the laser light to form a single laser beam and for directing the single laser beams onto the electronic circuit. It may be preferable that the generating means comprises a plurality of laser diodes. It may also be preferable that the combining means comprises a plurality of fiber optic cables which are bundled together at one end adjacent the circuit. It may additionally be preferable that the apparatus comprise means for focusing the laser light from the generating means into ., .

2i'~ (P'~

the combining means.
The invention may be further practiced by an apparatus for reflowing solder contacting an integrated circuit lead to connect the integrated circuit lead to a printed circuit board comprising means for generating a plurality of laser light beams, a plurality of fiber optic cables having an input end and an output end where said input end is optically coupled to the generating means to allow light from the generating means to propagate through the cables and having the output end of the cables being bundled together.
Homogenizer means optically coupled to the output end for combining the propagated light, within the fiber optic cables, so as to form a single laser light beam, and means for directing the single laser light beam from the homogenizer onto the integrated circuit lead so as to heat the lead, thereby reflowing the solder. It may be preferable that the apparatus further comprise means for enabling and dis-abling the generating means, and means for moving the circuit board so that the combined laser light beam can reflow another solder location on the printed circuit board.
The invention may also be practiced by an apparatus for melting solder, contacting an integrated circuit lead to connect the integrated circuit lead to a printed circuit board, where the apparatus comprises a plurality of laser diodes generating laser light, a plurality of fiber optic 2~

cables, each fiber cable having one end optically coupled to the laser diode, and the opposite end bundled together with the fiber cables such that the output from the bundle forms a plurality of closely spaced beams. A homogenizer means is connected to the bundled end of the fiber optic cables for comhining said plurality of light beams to form a single laser beam. Also provided is means for focusing the single laser beam on the integrated circuit so as to heat the lead, thereby melting the solder.
The invention may additionally be practiced by a system for melting solder contacting an integrated circuit lead to connect the integrated circuit lead to a printed circuit board comprising means for generating a plurality of focused light beams to simultaneously melt solder located at a plurality of locations on the circuit board, where the generating means comprises a plurality of laser diodes generating laser light, a plurality of fiber optic cable, each fiber optic cable having one end optically coupled to the laser diode so as to propagate the light through said cables and the opposite end of the fiber cables being bundled together with the other fiber optic cables, means for combining the light output from the plurality of fiber optic cables to form a single laser beam, means for focusing the single laser light beam on the integrated circuit lead so as to heat the lead, thereby reflowing solder. Also 2~ 4g provided is means for moving the circuit board so that the focused beams can heat another location on the circuit board.
It may be preferable that the invention further be practiced by a method of soldering an electronic chip lead having solder under the lead on a printed circuit board substrate, comprising the steps of generating a laser light beam from a diode laser, optically coupling the laser light beam into a fiber optic cable, forming a laser light beam from the iight output of the fiber optic cable, and focusing the formed laser light beam on the electronic chip lead so as to heat the lead, thereby melting solder.

2ilO(~-~49 Brief Description of the Drawings FIG. 1 is a perspective view of multi-branch fiber optic bundle having an array of fiber optic elements combining outputs from an array of laser diodes; and FIG. 2 is a perspective view of the soldering system having a plurality of fiber optic bundles, as shown in FIG. 1, operating on a printed circuit board.

2~ 9 Description of the Preferred Embodiments Referring to FIG. 1, there is shown a laser diode soldering system 10 including power supplies 12(a-n) and laser diode 14 being optically coupled to a fiber optic cables 16(a-n). An exemplary laser diodes 14(a-n) is Sld 304, manufactured by Sony Corporation. One end of the fiber optic cable 16 is optically coupled to each one of the laser diodes 14 through a series of optic focusing lenses 18 and 20. The other end of the fiber optic cable 16a is optically coupled to a homogenizer 21 and a series of PCB focusing lenses 22 and 24 which are mounted in a fiber jig 26.
- The power supplies 12(a-n) are held in place with a power supply mounting plate 27. The power supplies 12(a-n) are supported by a cooling plate 28. Protruding through the cooling plate 28 and connected to power supplies 12(a-n) are laser diode leads 30.
Mounted below the laser diode 14a is an optic focusing element holder 32 which holds optic focusing lenses 18 and 20. Optic focusing lenses 18 and 20 include a first optic focusing lens 18 and second optic focusing lens 20 for fo-cusing the laser diode 14a into fiber optic cable 16. Each lens is approximately 2mm in diameter. The fiber optic cable 16 is connected to the optic focusing element holder 32 through an optic connector 34.
The fiber optic cable 16a includes a shell 36 and a fiber 2i~ 49 optic strand 38. The fiber optic cable 16a is connected to the pptic focusing element holder 32 at one end and a fiber optic combiner 40 at the other end. The fiber optic combiner 40 bunches the fiber optic strands 38 disposed within a plurality of fiber optic cables 16(a-n) to form a single fiber optic bundle 41.
The homogenizer 21 is constructed by stretching silicon or glass to form an object as shown in ~IG. 1. The preferable dimensions are 2.5 inches long by .160 inches in diameter on the wide end and .004 inches in diameter on the small end.
The dimensions listed for homogenizer 21 are only suggested;
however, any dimension would be accepted as long as the wide diameter dimension can encompass the light output from the fiber strands and the small diameter dimension permit the PCB
focal lens 22 and 24 to focus the homogenizer 21 output laser lS light. It is also preferable that the homogenizer 21 butt up against the fiber optic strands. The homogenizer 21 combines a plurality of light outputs from fiber optic strands 38 within fiber optic bundle 81 and converts the combined light into a single laser beam that has enought intensity to reflow solder.
The fiber optic combiner 40 is inserted into the fiber jig 26. Also disposed in the fiber jig 26 is homogenizer 21, a first PC8 focusing lens 22 and a second PCB focusing lens 24. Disposed below the fiber jig 26 is integrated circuit package 42 mounted on a printed circuit board 44. The first PCB focusing lens 22 and the second PCB focusing lens 24 .

.

2i~ 49 focuses the laser light output from homogenizer 21 and direct that light onto the printed circuit board 44.
Connected to the power supplies 12(a-n) are power lines 46 and on/off control lines 48a-48n. The on/off control lines 48a-48n are connected to an external computer 49 to select-ively turn on and turn off each power supply 12(a-n).
During operation, the external computer turns on power supply 12(a-n) which enables laser diode 14(a-n). Laser diode 14a then generates a dispersing beam 50 of 1.06 microns of laser light which is then focused by first optic focusing lens 18. The focused beam 52 is then directed at fiber optic cable 16 by second optic focusing lens 20. The directed laser beam 54 is then propagated through fiber optic cable 16a along with directed laser beams from fiber optic cables 16b-16n toward the fiber jig 26. The light beam output 56 from the fiber optic bundle 41 is combined by homogenizer 21, focused by first PCB focusing lens 22 and then (light 58) directed by second PCB focusing lens 24 at integrated circuit package 42 on printed circuit board 44.
By using the fiber optic combiner 40 with homogenizer 21 to direct a multiplicity of fiber optic strands 38 at a first and second PCB focusing lens 22 and 24, laser diodes 14 can be used to solder integrated circuit packages 42 to printed circuit boards 44. Further, by using laser diodes 14 in combination with a plurality of fiber optic cables 16 connect ZiJ'(.~ 9 to combiner 40, and homogènizer 21, the magnitude of a laser diode 14 output energy (typically 0.5 to 1.0 watts) is magnified by an amount proportional to the number of laser diodes used. Ideally, enough laser diodes to generate 4 to 8 watts should be used to melt solder.
Referring to FIG. 2, there is shown a diode laser soldering system 60 using a multiplicity of fiber bundles 41.
This system has the power supplies 12(a-n), laser diodes 14(a-n), fiber bundles 41, jig 26 and printed circuit board 44, as shown in FIG. 1. Further, in this diode laser solder-ing system 60, a multiplicity of fiber bundles 41 are used to simultaneously solder multiple locations on the printed circuit board 44.
The power supplies 12(a-n) shown are mounted on a power supply mounting plate 27 and cooling plate 28, as shown in FIG. 1. Cooling plate 28 is mounted on support structure 29. Flowing between the power supply mounting plate 26 is a cool liquid (not shown) to provide a means for cooling the power supply 12(a-n) and laser diodes 14(a-n). The cooling plate 28 is kept at a cool temperature to increase the relia-bility and life expectancy of the laser diodes 14(a-n). Each of the power supplies 12(a-n) are individually controlled by an external computer.
The fiber optic combiners 40 are positioned in a single row in fiber jig 26. The spacing between fiber optic - 2~ 49 combiners 40 in fiber jig 26 is typically 50 to 100 mills.
There is shown in FIG. 2 is a single jig 26; however, a multiple number of jigs may be used. Ideally, two opposing jigs will be used which will be positioned to simultaneously heat solder on opposing sides of integrated circuit package.
Further, the jig 26 may be positioned on a bar 46 that allows the jig 26 to be finely adjusted to solder a variety of integrated circuit package shapes.
Printed circuit board 44 is mounted on a piece of posi-tioning e~uipment (not shownj such as Asymteck, Automove 300 System. This positioning equipment is electrically connected to an external computer 49 which changes the position of printed circuit board 44 to solder other locations.
Resting on top of printed circuit board 44 are inte-grated circuit packages 42 that have leads 62 along their outer edges which become soldered to printed circuit board 44.
The leads 62 are typically spaced .01 to .05 inches apart for surface mount packages. Constructed with printed circuit board 44 under leads 62 is a small amount of solder 64 which adheres leads 62 to printed circuit board 44 when lead 62 is heated.
During operation, printed circuit board 44 is positioned at a location where the laser light from the fiber optic bundles 41 will heat lead 62. The power supply 12 is then preferably enabled for a .75 to 1.25 second interval by the 2'~ 4~g external computer which energizes various sets of laser diodes 14. The laser light then propagates throughout the various fiber bundles, homogenizer 21, and is directed by PCB
focusing lenses 22 and 24 within jig 26, thereby simultan-eously heating different leads 62 of the integrated circuit packages 42. Accordingly, a multiplicity of locations on the integrated circuit package leads are simultaneously soldered.
The external computer, after soldering a first set of leads 62, will move the printed circuit board 44 in an X
and/or Y direction to heat a second set of leads 62. Thus, by having a multiplicity of laser diodes 12 turned on simul-taneously and combining the laser light output of those laser diodes 12(a-n) along with other sets of combined laser light from other laser diodes, a multiplicity of leads on an inte-grated circuit package 44 can be simultaneously heated.
Further, simultaneously heating different leads on an IC
package 42 located on a printed circuit board 44 will substantially speed up the soldering process.
This concludes the Description of the Preferred Embodiments. A reading of those skilled in the art will bring to mind many modifications and alternatives without departing from the spirit and scope of the invention.
Accordingly, it is intended that the invention only be limited by the following claims.

.

Claims (16)

1. An apparatus for directing laser light at an electronic circuit, said apparatus comprising:
means for generating a plurality of laser light beams;
and means optically coupled to said generating means for combining said laser light beams to form a single laser beam and for directing said single laser beam onto said electronic circuit.
2. The apparatus as recited in Claim 1 wherein said generating means comprises a plurality of laser diodes.
3. The apparatus as recited in Claim 1 wherein said combining means comprises a plurality of fiber optic cables being bundled together at one end adjacent said circuit.
4. The apparatus as recited in Claim 1 further comprising means for focusing said laser light from said generating means into said combining means.
5. An apparatus for reflowing solder contacting an integrated circuit lead to connect the integrated circuit lead to a printed circuit board, said apparatus comprising:
means for generating a plurality of laser light beams;

a plurality of fiber optic cables having an input end and an output end, said input end being optically coupled to said generating means to allow light from said generating means to propagate through said cables and said output end being bundled together;
homogonizer means optically coupled to said output end for combining said propagated light, within said fiber optic cables, so as to form a single laser light beam; and means for directing said single laser light beam from said homogonizer means onto the integrated circuit lead so as to heat said lead, thereby reflowing said solder.
6. The apparatus as recited in Claim 5 wherein said generating means has a plurality of laser diodes.
7. The apparatus as recited in Claim 5 further comprising means for focusing laser light from said generating means into said fiber optic cable.
8. The apparatus as recited in Claim 5 further comprising:
means for enabling and disabling said generating means;
and means for moving said circuit board so that said combined laser light beam can reflow another solder location on said printed circuit board.
9, An apparatus for melting solder contacting an integrated circuit lead to connect the integrated circuit lead to a printed circuit board, said apparatus comprising:
a plurality of laser diodes generating laser light;
a plurality of fiber optic cables, each fiber cable having one end optically coupled to said laser diode, and the opposite end bundled together with the other fiber cables such that the output from said bundle forms a plurality of closely spaced light beams; and homogonizer means connected to said bundled end of said fiber optic cables for combining said plurality of light beams to form a single laser beam; and means for focusing said single laser beam on said integrated circuit lead so as to heat said lead, thereby melting said solder.
10. The apparatus as recited in Claim 9 further comprising:
means for enabling and disabling said laser light beams;
and means for moving said circuit board so that said focused beam can heat another integrated circuit lead location.
11. The apparatus as recited in Claim 9 further comprising means for setting the duration that said laser diode is turned on to a time period between .75 and 1.25 seconds.
12. A system for melting solder contacting an integrated circuit lead to connect the integrated circuit lead to a printed circuit board comprising:
means for generating a plurality of focused laser beams to simultaneously melt solder located at a plurality of locations on said circuit board, said generating means comprising:
(a) a plurality of laser diodes generating laser light;
(b) a plurality of fiber optic cables, each fiber optic cable having one end optically coupled to said laser diode so as to propagate the light through said cables and the opposite end of said fiber cables being bundled together with the other fiber optic cables;
(c) means for combining the light output from said plurality of fiber optic cables to form a single laser light beam;
(d) means for focusing said single laser light beam on said integrated circuit lead so as to heat said lead, thereby reflowing solder; and means for moving said circuit board so that said focused beams can heat another lead location on said circuit board.
13. The apparatus as recited in Claim 12 wherein said soldering locations on an integrated circuit lead are located between .010 and .500 inches apart.
14. A method of soldering an electronic chip lead having solder under the lead on a printed circuit board substrate, comprising the steps of:
generating a laser light beam from a diode laser;
optically coupling said laser light beam into a fiber optic cable;
forming a laser light beam from the light output of said fiber optic cable; and focusing the formed laser light beam on said electronic chip lead so as to heat said lead, thereby melting solder.
15. The method as recited in Claim 14 further comprising the steps of:
enabling and disabling said generating means; and moving said electronic chip so that said focused laser beam can heat another electronic chip lead location.
16. The method as recited in Claim 14 further comprising the steps of setting the duration that said generating means is enabled to a time between .75 and 1.25 seconds.
CA002000449A 1988-10-24 1989-10-11 Diode laser soldering system Expired - Fee Related CA2000449C (en)

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US07/261,064 US4963714A (en) 1988-10-24 1988-10-24 Diode laser soldering system
US261,064 1988-10-24

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CA2000449C true CA2000449C (en) 1998-08-18

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Families Citing this family (28)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5269056A (en) * 1992-09-16 1993-12-14 Oea, Inc. Laser welding of wire strands to an electrode pin
DE4234342C2 (en) * 1992-10-12 1998-05-14 Fraunhofer Ges Forschung Process for material processing with laser radiation
ES2106520T3 (en) * 1993-05-19 1997-11-01 Fraunhofer Ges Forschung PROCEDURE THAT ALLOWS THE WORK OF MATERIALS BY RADIATION ISSUED BY DIODES.
US5422456A (en) * 1993-08-31 1995-06-06 Dahm; Jonathan S. Orbital head laser welder
US5580471A (en) * 1994-03-30 1996-12-03 Panasonic Technologies, Inc. Apparatus and method for material treatment and inspection using fiber-coupled laser diode
US5904868A (en) * 1994-06-16 1999-05-18 International Business Machines Corporation Mounting and/or removing of components using optical fiber tools
DE4429913C1 (en) * 1994-08-23 1996-03-21 Fraunhofer Ges Forschung Device and method for plating
US5509597A (en) * 1994-10-17 1996-04-23 Panasonic Technologies, Inc. Apparatus and method for automatic monitoring and control of a soldering process
US5562842A (en) * 1994-10-17 1996-10-08 Panasonic Technologies, Inc. Material treatment apparatus combining a laser diode and an illumination light with a video imaging system
DE19514285C1 (en) * 1995-04-24 1996-06-20 Fraunhofer Ges Forschung Device for forming workpieces with laser diode radiation
US5565119A (en) * 1995-04-28 1996-10-15 International Business Machines Corporation Method and apparatus for soldering with a multiple tip and associated optical fiber heating device
US5614113A (en) * 1995-05-05 1997-03-25 Texas Instruments Incorporated Method and apparatus for performing microelectronic bonding using a laser
US6072148A (en) * 1996-12-10 2000-06-06 Fraunhofer-Gesellschaft Zur Forderung Der Angewandten Forschung E.V. Device for producing connections between two respective contact elements by means of laser energy
US6160568A (en) * 1997-05-27 2000-12-12 Sdl, Inc. Laser marking system and method of energy control
KR100265066B1 (en) * 1997-08-28 2000-09-01 윤종용 Bonding apparatus of optical components for used non-contact soldering and method thereof
US6275250B1 (en) 1998-05-26 2001-08-14 Sdl, Inc. Fiber gain medium marking system pumped or seeded by a modulated laser diode source and method of energy control
US6043454A (en) * 1998-05-27 2000-03-28 Beamworks Ltd. Apparatus and method for in-line soldering
EP0964608A3 (en) 1998-06-12 2001-09-05 Ford Motor Company Method for laser soldering
US6168070B1 (en) 1998-10-14 2001-01-02 Visteon Global Technologies, Inc. Method for soldering DPAK-type electronic components to circuit boards
US6278078B1 (en) 1999-06-02 2001-08-21 Lockheed Martin Corporation Laser soldering method
DE10046361A1 (en) * 2000-09-20 2002-04-04 Hella Kg Hueck & Co Device and method for welding workpieces
US6627847B1 (en) * 2001-06-28 2003-09-30 Nortel Networks Limited Method and apparatus for through-body optical component attachment using laser soldering
KR100443987B1 (en) * 2002-02-14 2004-08-09 삼성전자주식회사 Soldering apparatus for collimator and soldering method thereof
DE10361521A1 (en) 2003-12-03 2005-07-07 Pac Tech - Packaging Technologies Gmbh Method of alternate contacting of two wafers especially a semiconductor and a functional component wafer uses selected laser wavelength to fuse contact metallization only
DE102004001276A1 (en) * 2004-01-08 2005-08-04 Mtu Aero Engines Gmbh Method for heating components
KR101522434B1 (en) * 2007-01-24 2015-05-21 팩 테크-패키징 테크놀로지스 게엠베하 Method and device for contacting, positioning and impinging a solder ball formation with laser energy
US8822881B2 (en) * 2007-10-31 2014-09-02 HGST Netherlands B.V. Selective soldering using fiber optic device
US20090120916A1 (en) * 2007-11-12 2009-05-14 L3 Communications Corporation Through-Via Laser Reflow Systems And Methods For Surface Mount Components

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3229095A (en) * 1963-05-20 1966-01-11 Ibm Apparatus for obtaining the difference of two incident optical radiations
US3383491A (en) * 1964-05-05 1968-05-14 Hrand M. Muncheryan Laser welding machine
US4327277A (en) * 1978-08-24 1982-04-27 Raytheon Company Method for laser soldering
NL8101826A (en) * 1981-04-14 1982-11-01 Philips Nv OPTICAL MULTIPLEX DEVICE.
US4535219A (en) * 1982-10-12 1985-08-13 Xerox Corporation Interfacial blister bonding for microinterconnections
JPH0797688B2 (en) * 1987-03-10 1995-10-18 富士通株式会社 Semiconductor device

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CA2000449A1 (en) 1990-04-24

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