US 20070269297 A1
Modular wafer transport and handling facilities are combined in a variety of ways deliver greater levels of flexibility, utility, efficiency, and functionality in a vacuum semiconductor processing system. Various processing and other modules may be interconnected with tunnel-and-cart transportation systems to extend the distance and versatility of the vacuum environment. Other improvements such as bypass thermal adjusters, buffering aligners, batch processing, multifunction modules, low particle vents, cluster processing cells, and the like are incorporated to expand functionality and improve processing efficiency.
1. A method for moving a wafer in a semiconductor manufacturing process that includes a tunnel having a vacuum environment, a plurality of ports, and a track for guiding cart motion within the tunnel, each one of the plurality of ports having an isolation valve that opens and closes the port and a robotic arm operable to reach through the port from outside the tunnel, the method comprising:
retrieving a wafer with a robotic arm;
position the wafer outside a port of the tunnel;
positioning a cart inside the port of the tunnel;
opening the port;
inserting the robotic arm into the tunnel and placing the wafer on the cart;
withdrawing the robotic arm from the tunnel; and
closing the port.
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66. A system comprising:
a tunnel including a plurality of ports, each one of the ports including an isolation valve for selective access to a vacuum environment of the tunnel through the port;
a passive cart operable to move within the vacuum environment of the tunnel among the plurality of ports; and
a plurality of robotic arms associated with the plurality of ports and outside the tunnel, each one of the plurality of robotic arms operable to move work pieces between the passive cart and at least one resource outside the tunnel.
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This application is a continuation-in-part of U.S. application Ser. No. 10/985,834 filed on Nov. 10, 2004 which claims the benefit of U.S. Prov. App. No. 60/518,823 filed on Nov. 10, 2003 and U.S. Prov. App. No. 60/607,649 filed on Sep. 7, 2004.
This application claims the benefit of U.S. Prov. App. No. 60/777,443 filed on Feb. 27, 2006; U.S. Prov. App. No. 60/779,684 filed on Mar. 5, 2006; U.S. Prov. App. No. 60/779,707 filed on Mar. 5, 2006; U.S. Prov. App. No. 60/779,478 filed on Mar. 5, 2006; U.S. Prov. App. No. 60/779,463 filed on Mar. 5, 2006; U.S. Prov. App. No. 60/779,609 filed on Mar. 5, 2006; U.S. Prov. App. No. 60/784,832 filed on Mar. 21, 2006; U.S. Prov. App. No. 60/746,163 filed on May 1, 2006; U.S. Prov. App. No. 60/807,189 filed on Jul. 12, 2006; and U.S. Prov. App. No. 60/823,454 filed on Aug. 24, 2006.
The entire contents of each of the foregoing applications is incorporated herein by reference.
1. Field of the Invention
The invention herein disclosed generally relates to semiconductor processing systems, and specifically relates to vacuum semiconductor processing work piece handling and transportation.
2. Description of the Related Art
Current semiconductor manufacturing equipment takes several different forms, each of which has significant drawbacks. Cluster tools, machines that arrange a group of semiconductor processing modules in a radius about a central robotic arm, take up a large amount of space, are relatively slow, and, by virtue of their architecture, are limited to a small number of semiconductor process modules, typically a maximum of about five or six. Linear tools, while offering much greater flexibility and the potential for greater speed than cluster tools, do not fit well with the current infrastructure of most current semiconductor fabrication facilities. Moreover, linear motion of equipment components within the typical vacuum environment of semiconductor manufacturing leads to problems in current linear systems, such as unacceptable levels of particles that are generated by friction among components. Several hybrid architectures exist that use a combination of a radial process module arrangement and a linear arrangement.
As semiconductor manufacturing has grown in complexity, it becomes increasingly necessary to transfer wafers among a number of different process modules or clusters of process modules, and sometimes between tools and modules that are separated by significant distances. This poses numerous difficulties, particularly when wafers are transferred between separate vacuum processing facilities. Transfers between vacuum environments, or between a vacuum and other processing environments often results in increased risk of particle contamination (due to the pumping and venting of wafers in load locks) as well as higher thermal budgets where wafers are either heated or cooled during transfers.
There remains a need for improved wafer transport and handling system for use in semiconductor manufacturing environments.
Provided herein are methods and systems used for improved semiconductor manufacturing handling, and transport. Modular wafer transport and handling facilities are combined in a variety of ways deliver greater levels of flexibility, utility, efficiency, and functionality in a vacuum semiconductor processing system. Various processing and other modules may be interconnected with tunnel-and-cart transportation systems to extend the distance and versatility of the vacuum environment. Other improvements such as bypass thermal adjusters, buffering aligners, batch processing, multifunction modules, low particle vents, cluster processing cells, and the like are incorporated to expand functionality and improve processing efficiency.
As used herein, “robot” shall include any kind of known robot or similar device or facility that includes a mechanical capability and a control capability, which may include a combination of a controller, processor, computer, or similar facility, a set of motors or similar facilities, one or more resolvers, encoders or similar facilities, one or more mechanical or operational facilities, such as arms, wheels, legs, links, claws, extenders, grips, nozzles, sprayers, end effectors, actuators, and the like, as well as any combination of any of the above. One embodiment is a robotic arm.
As used herein “drive” shall include any form of drive mechanism or facility for inducing motion. In embodiments it includes the motor/encoder section of a robot.
As used herein, “axis” shall include a motor or drive connected mechanically through linkages, belts or similar facilities, to a mechanical member, such as an arm member. An “N-axis drive” shall include a drive containing N axes; for example a “2-axis drive” is a drive containing two axes.
As used herein, “arm” shall include a passive or active (meaning containing motors/encoders) linkage that may include one or more arm or leg members, bearings, and one or more end effectors for holding or gripping material to be handled.
As used herein, “SCARA arm” shall mean a Selectively Compliant Assembly Robot Arm (SCARA) robotic arm in one or more forms known to those of skill in the art, including an arm consisting of one or more upper links connected to a drive, one or more lower links connected through a belt or mechanism to a motor that is part of the drive, and one or more end units, such as an end effector or actuator.
As used herein, “turn radius” shall mean the radius that an arm fits in when it is fully retracted.
As used herein, “reach” shall include, with respect to a robotic arm, the maximum reach that is obtained when an arm is fully extended. Usually the mechanical limit is a little further out than the actual effective reach, because it is easier to control an arm that is not completely fully extended (in embodiments there is a left/right singularity at full extension that can be hard to control).
As used herein, “containment” shall mean situations when the arm is optimally retracted such that an imaginary circle can be drawn around the arm/end effector/material that is of minimum radius.
As used herein, the “reach-to-containment ratio” shall mean, with respect to a robotic arm, the ratio of maximum reach to minimum containment.
As used herein, “robot-to-robot” distance shall include the horizontal distance between the mechanical central axis of rotation of two different robot drives.
As used herein, “slot valve” shall include a rectangular shaped valve that opens and closes to allow a robot arm to pass through (as opposed to a vacuum (isolation) valve, which controls the pump down of a vacuum chamber). For example, the SEMI E21.1-1296 standard (a published standard for semiconductor manufacturing) the slot valve for 300 mm wafers in certain semiconductor manufacturing process modules has an opening width of 336 mm, a opening height of 50 mm and a total valve thickness of 60 mm with the standard also specifying the mounting bolts and alignment pins.
As used herein, “transfer plane” shall include the plane (elevation) at which material is passed from a robot chamber to a process module chamber through a slot valve. Per the SEMI E21.1-1296 standard for semiconductor manufacturing equipment the transfer plane is 14 mm above the slot valve centerline and 1100 mm above the plane of the factory floor.
As used herein, “section” shall include a vacuum chamber that has one or more robotic drives in it. This is the smallest repeatable element in a linear system.
As used herein, “link” shall include a mechanical member of a robot arm, connected on both ends to another link, an end effector, or the robot drive.
As used herein, “L1,” “L2”, “L3” or the like shall include the numbering of the arm links starting from the drive to the end effector.
As used herein, “end effector” shall include an element at an active end of a robotic arm distal from the robotic drive and proximal to an item on which the robotic arm will act. The end effector may be a hand of the robot that passively or actively holds the material to be transported in a semiconductor process or some other actuator disposed on the end of the robotic arm.
As used herein, the term “SCARA arm” refers to a robotic arm that includes one or more links and may include an end effector, where the arm, under control, can move linearly, such as to engage an object. A SCARA arm may have various numbers of links, such as 3, 4, or more. As used herein, “3-link SCARA arm” shall include a SCARA robotic arm that has three members: link one (L1), link two (L2) and an end effector. A drive for a 3-link SCARA arm usually has 3 motors: one connected to L1, one to the belt system, which in turn connects to the end effector through pulleys and a Z (lift) motor. One can connect a fourth motor to the end effector, which allows for some unusual moves not possible with only three motors.
As used herein, “dual SCARA arm” shall include a combination of two SCARA arms (such as two 3 or 4-link SCARA arms (typically designated A and B)) optionally connected to a common drive. In embodiments the two SCARA arms are either completely independent or share a common link member L1. A drive for a dual independent SCARA arm usually has either five motors: one connected to L1-A, one connected to L1-B, one connected to the belt system of arm A, one connected to the belt system of arm B, and a common Z (lift) motor. A drive for a dual dependent SCARA arm usually has a common share L1 link for both arms A and B and contains typically four motors: one connected to the common link L1, one connected to the belt system for arm A, one connected to the belt system for arm B, and a common Z (lift) motor.
As used herein, “4-link SCARA arm” shall include an arm that has four members: L1, L2, L3 and an end effector. A drive for a 4-link SCARA arm can have four motors: one connected to L1, one to the belt systems connected to L2 and L3, one to the end effector and a Z motor. In embodiments only 3 motors are needed: one connected to L1, one connected to the belt system that connects to L2, L3 and the end effector, and a Z motor.
As used herein, “Frog-leg style arm” shall include an arm that has five members: L1A, L1B, L2A, L3B and an end effector. A drive for a frog-leg arm can have three motors, one connected to L1A—which is mechanically by means of gearing or the like connected to L1B—, one connected to a turret that rotates the entire arm assembly, and a Z motor. In embodiments the drive contains three motors, one connected to L1A, one connected to L1B and a Z motor and achieves the desired motion through coordination between the motors.
As used herein, “Dual Frog-leg style arm” shall include an arm that has eight members L1A, L1B, L2A-1, L2A-2, L2B-1, L2B-2 and two end effectors. The second link members L2A-1 and L2B-1 form a single Frog-leg style arm, whereas the second link members L2A-2 and L2B-2 also form a single Frog-leg style arm, however facing in an opposite direction. A drive for a dual frog arm may be the same as for a single frog arm.
As used herein, “Leap Frog-leg style arm” shall include an arm that has eight members L1A, L1B, L2A-1, L2A-2, L2B-1, L2B-2 and two end effectors. The first link members L1A and L1B are each connected to one of the motors substantially by their centers, rather than by their distal ends. The second link members L2A-1 and L2B-1 form a single Frog-leg style arm, whereas the second link members L2A-2 and L2B-2 also form a single Frog-leg style arm, however facing in the same direction. A drive for a dual frog arm may be the same as for a single frog arm.
Disclosed herein are methods and systems for combining a linkable, flexible robotic system with a vacuum tunnel system using moveable carts for carrying one or more wafers in vacuum between process modules. The vacuum tunnel cart may be employed to transfer wafers between process modules or clusters, while a linkable robotic system is employed within each module or cluster for local wafer handling. The carts may employ any transportation medium suitable for a vacuum environment, such as magnetic levitation/propulsion.
Disclosed herein are also various configurations of vacuum transport systems in which heterogeneous handling systems are combined in a modular fashion to allow for more diverse functionality within a single process environment. In general, robots may be provided for wafer handling inside and between process modules that are in proximity to each other, while allowing for rapid, convenient transport of wafers between process cells that are relatively distant. Such heterogeneous handling systems may include, for example, systems in which robotic arms, such as SCARA arms, are used to handle wafers within process modules or clusters, while carts or similar facilities are used to transport wafers between process modules or clusters. A cart or similar facility may include a levitated cart, a cart on a rail, a tube system, or any of a wide variety of cart or railway systems, including various embodiments disclosed herein.
The methods and systems disclosed herein also include various configurations of robot handling systems in combination with cart systems, including ones in which cart systems form “U” and “T” shapes, circuits, lines, dual linear configurations (including side-by-side and above and below configurations) and the like.
Disclosed herein are methods and systems for supporting vacuum processing and handling modules in vacuum semiconductor processing systems. The pedestal support systems herein disclosed may precisely position vacuum modules to facilitate proper vacuum sealing between adjacent modules. In embodiments, the pedestal's cylindrical shape affords opportunity for convenient manufacturing methods while providing stability to the supported vacuum module with a small footprint.
In embodiments, the pedestal support system further may incorporate a robot motor mechanism for a robot operating within the vacuum module, further reducing the overall size and cost of the vacuum processing system.
A pedestal support system with a rolling base may also provide needed flexibility in reconfiguring processing and handling modules quickly and cost effectively.
These and other systems, methods, objects, features, and advantages of the present invention will be apparent to those skilled in the art from the following detailed description of the preferred embodiment and the drawings. All documents mentioned herein are hereby incorporated in their entirety by reference.
The foregoing and other objects and advantages of the invention will be appreciated more fully from the following further description thereof, with reference to the accompanying drawings, wherein:
In embodiments the components of the system can be controlled by a software controller, which in embodiments may be a central controller that controls each of the components. In embodiments the components form a linkable handling system under control of the software, where the software controls each robot to hand off a material to another robot, or into a buffer for picking up by the next robot. In embodiments the software control system may recognize the addition of a new component, such as a process module or robot, when that component is plugged into the system, such as recognizing the component over a network, such as a USB, Ethernet, firewire, Bluetooth, 802.11a, 802.11b, 802.11g or other network. In such embodiments, as soon as the next robot, process module, or other component is plugged in a software scheduler for the flow of a material to be handled, such as a wafer, can be reconfigured automatically so that the materials can be routed over the new link in the system. In embodiments the software scheduler is based on a neural net, or it can be a rule-based scheduler. In embodiments process modules can make themselves known over such a network, so that the software controller knows what new process modules, robots, or other components have been connected. When a new process module is plugged into an empty facet, the system can recognize it and allow it to be scheduled into the flow of material handling.
In embodiments the software system may include an interface that permits the user to run a simulation of the system. The interface may allow a user to view the linking and configuration of various links, robotic arms and other components, to optimize configuration (such as by moving the flow of materials through various components, moving process modules, moving robots, or the like), and to determine what configuration to purchase from a supplier. In embodiments the interface may be a web interface.
The methods and system disclosed herein can use optional buffer stations 4010 between robot drives. Robots could hand off to each other directly, but that is technically more difficult to optimize, and would occupy two robots, because they would both have to be available at the same time to do a handoff, which is more restrictive than if they can deposit to a dummy location 4010 in-between them where the other robot can pick up when it is ready. The buffer 4010 also allows higher throughput, because the system does not have to wait for both robots to become available. Furthermore, the buffers 4010 may also offer a good opportunity to perform some small processing steps on the wafer such as heating, cooling, aligning, inspection, metrology, testing or cleaning.
In embodiments, the methods and systems disclosed herein use optional vacuum isolation valves 4006 between robot areas/segments 4012. Each segment 4012 can be fully isolated from any other segment 4012. If a robot handles ultra clean and sensitive materials (e.g., wafers) in its segment 4012, then isolating that segment 4012 from the rest of the system may prevent cross-contamination from the dirtier segment 4012 to the clean segment 4012. Also the manufacturer can now operate segments 4012 at different pressures. The manufacturer can have stepped vacuum levels where the vacuum gets better and better further into the machine. The big advantage of using vacuum isolation valves 4006 between segments 4012 may be that handling of atomically clean wafers (created after cleaning steps and needing to be transported between process modules without contamination from the environment) can be done without out-gassing from materials or wafers in other parts of the system entering the isolated chamber segment 4012.
In embodiments, vacuum isolation between robots is possible, as is material buffering between robots, such as using a buffer module 4010, a mini-process module or an inspection module 4010.
Different forms of robots can be used in semiconductor manufacturing equipment, whether a cluster tool or a linear processing machine such as disclosed in connection with
The 4-link arm 6004 is advantageous in that it folds in a much smaller containment ratio than a 3-link SCARA arm 6002, but it reaches a lot further than a conventional 3-link SCARA 6002 for the same containment diameter. In combination with the ability to have a second drive and second 4-link arm 6004 mounted on the top of the system, it may allow for a fast material swap in the process module. The 4-link SCARA arm 6004 may be mounted, for example, on top of a stationary drive as illustrated, or on top of a moving cart that provides the transmission of the rotary motion to actuate the arms and belts. In either case, the 4-link arm 6004, optionally together with a second 4-link arm 6004, may provide a compact, long-reach arm that can go through a small opening, without colliding with the edges of the opening.
Another feature is that only two motors, just like a conventional SCARA arm, may be needed to drive the 4-link arm. Belts in the arm may maintain parallelism. Parallelism or other coordinated movements may also be achieved, for example, using parallel bars instead of belts. Generally, the use of only two motors may provide a substantial cost advantage. At the same time, three motors may provide a functional advantage in that the last (L4) link may be independently steered, however the additional belts, bearings, connections, shafts and motor may render the system much more expensive. In addition the extra belts may add significant thickness to the arm mechanism, making it difficult to pass the arm through a (SEMI standard) slot valve. Also, the use of fewer motors generally simplifies related control software.
Another feature of the 4-link SCARA arm disclosed herein is that the wrist may be offset from centerline. Since the ideal system has a top-mount 9008 as well as a bottom 9004 mount 4-link arm, the vertical arrangement of the arm members may be difficult to adhere to if the manufacturer also must comply with the SEMI standards. In a nutshell, these standards specify the size and reach requirements through a slot valve 4006 into a process module. They also specify the level above centerline on which a wafer has to be carried. Many existing process modules are compliant with this standard. In systems that are non-compliant, the slot valves 4006 are of very similar shape although the opening size might be slightly different as well as the definition of the transfer plane. The SEMI standard dimensional restrictions require a very compact packaging of the arms. Using an offset wrist allows the top 9008 and bottom 9004 arms to get closer together, making it easier for them to pass through the slot valve 4006. If the wrist is not offset, then the arms need to stay further apart vertically and wafer exchanges may take more time, because the drives need to move more in the vertical direction. The proposed design of the top arm does not require that there is a wrist offset, but a wrist offset may advantageously reduce the turn radius of the system, and allows for a better mechanical arm layout, so no interferences occur.
Referring still to
In embodiments the air return mechanism may feature a storage area 14014 for empty carriers 14008, probably located at the very end and behind the location of the load lock 14010. The reason for this is that when the load lock 14010 releases a carrier 14018, the gripper 14004 can grip the carrier 14018 and move it forward slightly. The gripper 14004 can then release the full carrier 14018, move all the way back and retrieve an empty carrier 14008, place it on the load lock 14010. At this point the load lock 14010 can evacuate. The gripper 14004 can now go back to the full carrier 14018 and move it all the way to the front of the system. Once the carrier 14018 has been emptied by the EFEM, it can be returned to the very back where it waits for the next cycle.
It is also possible to put the lift in the load lock rather than using the vertical motion in the gripper, but that would be more costly. It would also be slightly less flexible. A manufacturer may want a vertical movement of the carrier 14018 in a few places, and putting it in the gripper 14004 would be more economical because the manufacturer then only needs one vertical mechanism.
The methods and systems disclosed herein offer many advantages in the handling of materials or items during manufacturing processes. Among other things, vacuum isolation between robots may be possible, as well as material buffering between robots. A manufacturer can return finished wafers over the top of the system without going through vacuum, which can be a very substantial advantage, requiring only half the necessary handling steps, eliminating cross contamination between finished and unfinished materials and remaining compatible with existing clean room designs. When a manufacturer has relatively dirty wafers entering the system, the manufacturer may want to isolate them from the rest of the machine while they are being cleaned, which is usually the first step in the process. It may be advantageous to keep finished or partially finished materials away from the cleaning portion of the machine.
Other advantages may be provided by the methods and systems disclosed herein. The dual arms (top mounted and bottom mounted) may work in coordinated fashion, allowing very fast material exchanges. Regardless of the exact arm design (3-link, 4-link or other), mounting an arm in the lid that is not mechanically connected to the arm in the bottom can be advantageous. The link lengths of the 4-link SCARA arm provided herein can be quite advantageous, as unlike conventional arms they are determined by the mechanical limits of slot valves and chamber radius. The 4-link SCARA arms disclosed herein are also advantageous in that they can use two motors for the links, along with a Z motor, rather than three motors plus the Z motor.
A linear vacuum system where materials exit in the rear may offer substantial benefits. Another implementation may be to have both the entry system and exit system installed through two opposing walls.
The 4-link SCARA arm disclosed herein may also allow link L3 to swing into and over link L2 for the top robot drive. This may not be easily done with the 3-link SCARA, nor with existing versions of 4-link SCARA arms, because they have the wrong link lengths.
The gripper for carriers and the multiple carrier locations in the linear system may also offer substantial benefits in materials handling in a linear manufacturing architecture. Including vertical movement in the gripper and/or in the rear load lock may offer benefits as well.
While the invention has been described in connection with certain preferred embodiments, one of ordinary skill in the art will recognize other embodiments that are encompassed herein.
Several automated training applications have been developed, but they may involve running the robotic arm into a physical obstacle such as a wall or edge. This approach has significant downsides to it: physically touching the robot to an obstacle risks damage to either the robot or the obstacle, for example many robot end effectors are constructed using ceramic materials that are brittle, but that are able to withstand very high wafer temperatures. Similarly, inside many process modules there objects that are very fragile and easily damaged. Furthermore, it may not be possible to employ these auto-training procedures with certain materials, such as a wafer 31008 present on the robot end effector. Moreover, the determination of vertical position is more difficult because upward or downward force on the arm caused by running into an obstacle is much more difficult to detect.
In the systems described herein, a series of sensors 35002-35010 may include horizontal sensors 35004-35010 and vertical sensors 35002. This combination of sensors 35002-35010 may allow detection, for example through optical beam breaking, of either a robotic end effector, arm, or a handled object. The vertical sensor 35002 may be placed slightly outside the area of the wafer 31008 when the robotic arm 35018 is in a retracted position. The vertical sensor 35002 may also, or instead, be placed in a location such as a point 35012 within the wafer that is centered in front of the entrance opening and covered by the wafer when the robot is fully retracted. In this position the sensor may be able to tell the robotic controller that it has successfully picked up a wafer 31008 from a peripheral module.
Horizontal sensors 35004-35010 may also be advantageously employed. In vacuum cluster tools, horizontal sensors 35004-35010 are sometimes impractical due to the large diameter of the vacuum chamber, which may make alignment of the horizontal sensors 35004-35010 more complicated. In the systems described above, the chamber size may be reduced significantly, thus may make it practical to include one or more horizontal sensors 35004-35010.
Additionally, during a subsequent rotation and movement, a second line segment “c-d” 37008 37010 may be detected when the wafer 37001 edges pass through the sensor. Again, the midpoint between “c” 37008 and “d” 37010 should coincide with the center of the end effector, and may permit a measurement or confirmation of wafer centering.
The above method may allow the robot to detect the wafer 37001 as well as determine if the wafer 37001 is off-set from the expected location on the end effector.
The combination of horizontal and vertical sensors 35002-35010 may allow the system to be taught very rapidly using non-contact methods: the robotic arm and end effectors may be detected optically without the need for mechanical contact. Furthermore, the optical beams can be used during real-time wafer 37001 handling to verify that wafers 37001 are in the correct position during every wafer 37001 handling move.
In many instances it may be difficult or impossible to put instrumentation on an object 44014 used to train a robot, because the wires that are needed to power and communicate to the instruments and sensors interfere with proper robotic motion or with the environment that the robot moves through. By employing a wireless connection to the object, the problem of attached wires to the object may be resolved.
The object 44014 can be equipped with numerous sensors of different types and in different geometrically advantageous patterns. In the present example, the sensors 1 through 6 (44010) are laid out in a radius equal to the radius of the target object 44008. In embodiments these sensors are proximity sensors. By comparing the transient signals from the sensors 44010, for example sensor 1 and sensor 6, it can be determined if the object 44014 is approaching a target 44008 at the correct orientation. If the target 44008 is not approached correctly, one of the two sensors 44010 may show a premature trigger. By monitoring multiple sensors 44010, the system may determine if the object 44010 is properly centered above the target 44008 before affecting a handoff. The sensors 44010 can be arranged in any pattern according to, for example, efficiency of signal analysis or any other constraints. Radio frequency signals also advantageously operate in a vacuum environment.
Preheating the wafers 48008 may reduce condensation and particles while reducing process time. At the same time, the wafers 48008 may be too hot when exiting the system, such that they present a safety hazard, or melt handling and support materials such as plastic. Internal temperatures of about 80 to 100° C. degrees, and external temperatures of about 50° C. degrees or less may, for example, meet these general concerns.
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A variety of techniques may be used to handle and transport wafers within semiconductor manufacturing facilities such as those described above. It will be understood that, while certain processing modules, robotic components, and related systems are described above, other semiconductor processing hardware and software may be suitably employed in combination with the transport and handling systems described below. All such variations and modifications that would be clear to one of ordinary skill in the art are intended to fall within the scope of this disclosure.
In order to facilitate discussion of various transport/handling schemes, the combination of the transfer robot 6131 with one or more process modules 2002 is referred to herein as a process cell 6170. It should be understood that process cells may have many configurations including conventional or unconventional process modules and/or cluster tools that perform a wide range of processes, along with associated or additional robotics for transferring wafers. This may include commercially available process modules, custom process modules, and so forth, as well as buffers, heaters, metrology stations, or any other hardware or combination of hardware that might receive wafers from or provide wafers to a wafer transportation system. Process modules 2002 and/or process cells 6170 may be disposed in various configurations, such as in clusters, aligned along the sides of a line or curve, in square or rectangular configurations, stacked vertically, or the like. Similarly, one or more robots 6131 that service process cells 6170 can be configured many ways, to accommodate different configurations of process modules, including in vertically stacked or opposing positions, in line with each other, or the like.
The process group 6100 may further include one or more isolation valves 6180 such as slot valves or the like that selectively isolate vacuum zones within the group 6100 and facilitate work piece interchange between vacuum zones. The isolation valves 6180 may provide control to maintain a proper vacuum environment for each work piece during one or more processing steps, while permitting intermittent movement of work pieces between vacuum zones.
In the embodiment of
The transport cart 6140 may transport a work piece, such as a semiconductor wafer, to a position accessible by the work piece handling vacuum module 6130, and may selectively transport items such as wafers or other workpieces to a process module 2002 for processing. The transport cart 6140 can be realized in many embodiments, including a magnetically levitated and/or driven cart, a cart on a railway, a cart with an arm or extending member, a cart on wheels, a cart propelled by a telescoping member, a cart propelled by an electric motor, a cart that is capable of tipping or tilting, a cart that may traverse a sloping tunnel to move a work piece or work pieces from one height to another, an inverted cart suspended from a transport track, a cart that performs processing or one of several functions on a work piece during transport, or the like.
The cart 6140 may be on gimbals, or suspended as a gondola, to accommodate variations in horizontal alignment of the path of the cart 6140. Similarly, the cart may include a wafer holder (e.g., supports, shelves, grippers, or the like) that is on gimbals, or that is suspended from a wire or the like, such that the wafer holder maintains a substantially level orientation while the cart traverses an incline. Thus, in certain embodiments, the cart may traverse inclines, declines, or direct vertical paths while maintaining a wafer or other workpiece in substantially uniform, level horizontal alignment. Such a cart may have a selectively fixed horizontal alignment so that movements such as acceleration or deceleration in a horizontal plane do not cause tipping of the workpiece. In other embodiments, the cart may be permitted to tip during acceleration or deceleration in order to stabilize a position of the work piece on the cart 6140.
The cart 6140 may be made of materials suitable for use in vacuum, such as materials that mitigate generation of undesirable particles or materials that have low outgassing characteristics. In an embodiment, the cart 6140 is a simple cart, without a robotic arm. As a significant advantage, using an armless cart mechanically simplifies the cart, thus saving on maintenance, repairs, and physical contamination of vacuum environments. In such embodiments, each entrance/egress from the cart path preferably includes a robot or similar device to place and retrieve workpieces on the cart.
In order to distinguish between various possible implementations, the following description employs the term “passive cart” to denote a cart without a robotic arm or other mechanism for loading and unloading wafers. As noted above, this configuration provides a number of advantages in terms of simplicity of design and in-vacuum implementation, and provides the additional advantage of mitigating the creation of contaminants from mechanical activity. The term “active cart” is employed herein to denote a cart that includes a robotic arm. Active carts present different advantages, in particular the improved versatility of having a robotic arm available arm at all times with the cart and a relaxation of the corresponding requirement for wafer handling hardware at each port 6180 of the tunnel 6150. It will be understood that, while providing a useful vocabulary for distinguishing between carts with and without robots, a so-called “passive cart” may nonetheless have other mechanical or active components such as wheels, sensors, and so forth.
The cart 6140 may include space for a single wafer or the like. In some embodiments, the cart 6140 may include a plurality of shelves so that multiple wafers can be transported by the cart. The shelves may have a controllable height or the like in order to accommodate access to different ones of the wafers by a fixed-height robot, or the shelves may have a fixed height for use with robotic handlers having z-axis control. In still other embodiments, the cart 6104 may include a single surface having room for multiple wafers. While multi-wafer variations require an additional degree of processing control (to account for multiple possible positions of a wafer on each cart), they also provide increased flexibility and capacity to the systems described herein. In other embodiments, the cart 6140 may be adapted to carry a multi-wafer carrier or for concurrent handling and/or processing of multiple wafers.
The cart 6140 may provide supplemental functionality. For example, the cart 6140 may include a wafer cooling or heating system that controls wafer temperature during transport. The cart 6104 may also, or instead, include wafer center finding sensors, wafer metrology sensors, and the like. It will be appreciated that, while a range of possible supplemental functions may be supported by the cart 6104, those functions that employ solid state sensing and processing may be preferably employed to facilitate preservation of a clean processing environment.
The tunnel 6150 may be of any cross-sectional shape and size suitable for accommodating the transport cart 6140 and any associated payload. In general, the tunnel 6150 will be capable of maintaining an environment similar or identical to various process cells connected thereto, such as a vacuum. The vacuum environment may be achieved, for example by providing slot valves or the like for independent vacuum isolation of each port 6180 (generally indicated in
In some embodiments, the tunnel 6150 may maintain an intermediate environment where, for example, different process cells employ different vacuum levels, or include other gasses associated with processing. While depicted as a straight line, the tunnel 6150 may include angles, curves, and other variations in path suitable for accommodating travel of the transport cart 6140. In addition, the tunnel 6150 may include tracks or other surfaces consistent with the propulsion system used to drive the transport cart 6140 from location to location. In some embodiments, the tunnel 6150 may include inclines or other variations that accommodate changes in height among various process cells connected thereto. All such variations that can be used with a cart 6140 to move wafers or other workpieces within a processing environment are intended to fall within the scope of this disclosure.
In operation, work pieces may move into the linear process cell by manipulation with the transfer robot 6131 from transport cart 6140. The transfer robot 6131 may either transfer the work piece to transfer robot 6632 or to one of two process modules 2002A or 2002B. The transfer robot 6632 may receive a work piece to be processed from the transfer robot 6631 and either transfers it to the transfer robot 6633 or to one of two process modules 2002C or 2002D. The transfer robot 6633 may receive a work piece to be processed from the transfer robot 6632. Finished work pieces may be transferred to consecutive, adjacent transfer robots until passing through the transfer robot 6131 onto tunnel transport cart 6140. In one embodiment, a load lock may be provided at one end of the linear system 6610 to permit the addition or removal of wafers at an opposing end of the linear system 6610 from the transport cart interface.
In one aspect, the selection of process cells connected to the tunnel 6150 may be advantageously made to balance or control system-wide throughput. Thus, for example, process cells with relatively quick process times can be combined with a suitable number of parallel process cells providing a different process with a slower process time. In this manner, a process cell with quick process time can be more fully utilized by servicing multiple downstream or upstream process cells within a single vacuum environment. More generally, using the transport cart 6140 and tunnel 6150, or a number of such carts and tunnels, greater design flexibility is provided for fabrication process layouts to balance load and/or improve utilization among process cells with varying process times and throughput limitations.
In the embodiment of
It will be appreciated that the system may handle multiple wafers at one time. In some embodiments, wafers may flow uniformly from one entrance (e.g., a first front end module 7020) to one exit (e.g., a second front end module 6110). However, the depicted layout can readily accommodate wafers simultaneously traveling in the opposing direction, or wafers entering and exiting through a single one of the front end modules, or combinations of these. As noted above, this permits the deployment of fabrication facilities that significantly improve utilization of particular processing tools, and permits the implementation of numerous, different processes within a single fabrication system.
For configurations that include process steps of substantially different durations, slower processes 7410 may be supported by a relatively large number of associated tools (which may be deployed as clusters or linear groups) in order to balance throughput for the combined processing system 7400. Thus, using the transport systems described herein, conceptual bottlenecks in complex semiconductor manufacturing processes can be addressed by simply expanding capacity around longer processes, thereby improving utilization of tools having relatively shorter processes. By way of example and not of limitation, processes having relative durations of 1 (preclean):2 (PVD):10 (CVD) can be supported by a facility having 2 preclean tools, 20 CVD processing tools, and 4 PVD processing tools working together in a single vacuum environment supported by a cart 6140 and tunnel 6150. While preserving this ratio, the total number of each tool type may be expanded or contracted according to further process constraints such as the throughput capacity of front end modules or other separate systems within a fabrication facility.
An alternate embodiment may include a tunnel configured as a loop to allow transport carts that have reached the end process cell to continue in a loop to an input interface module to accept a new work piece for transport. The loop may be configured either as a horizontal loop or a vertical loop, or a combination of these.
In the configuration of
This configuration permits a work piece to be processed on one or more of the processes associated with one or more of the transport vacuum tunnels without the work piece having to be removed from the vacuum environment. Linking transport vacuum tunnels by transfer robots allows for isolation of one or more of the transport vacuum tunnels, thus permitting adjacent use of different vacuum environments and enabling independent operation of the processes associated with each of the transport vacuum tunnels.
While numerous arrangements of semiconductor handling and processing hardware have been described, it will be understood that numerous other variations are possible to reduce floor space usage and shorten the distance between related processing groups. For example, vacuum transport systems may be usefully deployed underneath floors, behind walls, on overhead rails, or in other locations to improve the layout of fabrication facilities, such as by clearing floor space for foot traffic or additional machinery. In general, these embodiments may employ vertical lifts in combination with robotic arms and other handling equipment when loading or transferring wafers or other work pieces among processing modules.
In such a situation it may be desirable to provide a vacuum cart and tunnel system as generally disclosed herein to remove one or more wafers from the flow under vacuum to a standalone metrology or lithography system 9205. A cart 9208 may be positioned in the flow at a location 9201 between process modules to receive a wafer. It will be understood that, while a particular location is identified in
As depicted in
As noted above, the cart and work piece handling vacuum module systems described herein may be combined with simple vacuum tube extensions that may be disposed in-line with, or adjacent to work piece handling vacuum modules 6130 to facilitate greater levels of flexibility in the arrangement and interconnection of different processing hardware. Referring to
In addition one or more link modules 9302, 9308 may be provided to interconnect any of the above hardware. In addition to accommodating hardware spacing (in the same manner as vacuum extensions), a module 9302, 9308 may provide a variety of supplemental functions associated with a semiconductor processing system. For example, a link module 9308 may provide storage, operating as a buffer in a wafer process flow. A link module 9302 may provide metrology, measurement, or testing of wafers. A link module 9308 may provide operator access to a work piece, in which case the link module 9308 may include an isolation valve and vacuum pump. A link module 9302, 9308 may provide thermal management, such as by cooling or heating a wafer between processes. A link module may provide buffering and/or aligning capacity for single and/or multiple wafers such as provided by the buffering aligner apparatus 9700 described below. With respect to the buffering aligner, it will be understood that this use in a link module is an example only, and that a buffering alignment module may also or instead be usefully employed at other points in a process, such as in an equipment front end module. For example, if process chambers process wafers in mini-batches of 2, 3, 4 or 5 or more wafers, then it may be efficient to employ a buffering system at an aligner to prevent the alignment time from becoming a bottleneck in a larger process. Once the proper number of wafers has been prepared in the buffer of an EFEM, an atmospheric robot can affect a batch transfer of these (aligned) wafers to a load lock.
A link module may provide bypass capabilities, permitting two or more wafers to cross paths between process modules. More generally, a link module 9302, 9308 may provide any function that can be usefully performed in a vacuum environment between processing tools, including any of those identified above as well as combinations of same.
As a significant advantage, such multi-function link modules can reduce the need for additional processing modules, and reduce wait times between processing modules in a variety of ways. For example, bypass capabilities alleviate the need to complete remove one wafer from a cluster or linear processing module before adding another, since conflicting paths can be resolved within the bypass module. As another example, thermal management within link modules can reduce the need to wait for heating or cooling once a wafer reaches a particular tool. Other advantages will be apparent to one of ordinary skill in the art.
More generally, using the systems and methods described herein, a workpiece may be processed during transport and/or wait time between process tools. This may include processing in a link module 9302, 9308 as described above, as well as processing on a transport cart 6150, processing in a tunnel 6150, processing in a buffer, processing in a load lock, or processing at any other point during wafer handling between process tools.
Such a vacuum module may include an environmentally sealable enclosure to capture and thermally adjust a work piece in transition before the work piece is transferred to the next process step, while allowing coordinated pass through of other work pieces during the heating or cooling process.
It may be advantageous to include such a vacuum module in close proximity to a process chamber in a vacuum semiconductor processing system, such that a work piece may be heated or cooled to meet the particular needs of the process chamber for improved processing. Additionally, including and utilizing such a vacuum module can facilitate effective use of process chambers in the system by allowing a second work piece to be brought up to temperature as a first work piece is being processed.
Additionally, a work piece may be returned to ambient temperature immediately after it is taken from a process chamber, before it is handled by additional transfer robots, thereby eliminating any waiting time while the work piece cools before transferring another work piece to the process chamber.
It may also be beneficial to include a bypass thermal adjuster in combination with cart/tunnel systems in a semiconductor processing system to further facilitate flexibility, utility, process efficiency, and the like. Disclosed in this specification are examples of beneficial configurations of the bypass thermal adjuster in combination with work piece handling vacuum modules, carts 6140, tunnels 6150, and other process and function modules.
Various embodiments of tunnel and cart systems have been described above, as well as other linking hardware such as vacuum extensions and linking modules. In general, these systems support modular use and reuse of semiconductor processing tools from different vendors, and having different processing times and other characteristics. In one aspect, such systems may be further improved through variations such as different tunnel shapes (curvilinear, L, U, S, and/or T shaped tunnels) and shapes supporting two, three, four, or more equipment front end modules. In another aspect, additional hardware may be employed to provide further flexibility in the design and use of semiconductor manufacturing systems. The following description identifies a number of additional components suitable for use with the systems described herein.
The configurable vacuum module 9502 may include a removable bottom plate which may include a work piece heater for preheating a work piece before the handling robot 6130 transfers the work piece into an attached processing module.
The configurable vacuum module 9502 may include storage for a plurality of work pieces. As an example, work pieces may be placed by the handling robot 6130 on a rotating platform within the configurable vacuum module 9502. The maximum number of work pieces may be determined by the size of each work piece and the size of the rotating platform. Alternatively the configurable vacuum module 9502 may include a surface adapted to support semiconductor work pieces, with the surface sufficiently large to allow a plurality of work pieces to be placed on the surface in a non-overlapping arrangement. The storage within the configurable vacuum module 9502 may be enabled by a work piece elevator with a plurality of work piece support shelves, wherein the elevator can be controlled to adjust height for selection of a particular shelf to be accessed by the handling robot 6130.
The configurable vacuum module 9502 may include metrology devices for purposes of collecting metrics about the work piece. As an example, a metrology device such as an optical sensor, can be used to detect the presence of a work piece in the configurable vacuum module 9502 and initiate an automated inspection of the work piece by a machine vision system. Such metrics are useful to maintain and improve control and quality of the fabrication processes being performed on the work piece in associated process modules.
The configurable vacuum module 9502 may further include interface ports 9504 capable of supporting ultra high vacuum operation. The ultra high vacuum may be achieved by configurable vacuum module 9502 wherein the configurable vacuum module 9502 is constructed with materials such as stainless steel known to support an ultra high vacuum environment. Such an environment may be useful for removing trace gasses in the environment and reducing the introduction of gasses caused by outgassing of materials in the environment.
The configurable vacuum module 9502 may provide a load lock function for the vacuum processing environment. Such a function may be useful in work piece exchange between a user ambient environment and the vacuum processing environment by allowing work pieces supplied by a user to be introduced into the vacuum environment by sealing the work pieces in the configurable vacuum module 9502 and generating a vacuum environment around the sealed work pieces.
The configurable vacuum module 9502 may support fabrication processing of a work piece such as rapid thermal anneal or in-situ wafer cleaning. Rapid thermal anneal may be beneficial in a semiconductor vacuum processing environment for achieving specific changes in a semiconductor work piece such as activating dopants, and densifying deposited films. In-site wafer cleaning can be needed to remove residue or particles deposited during processing in the chambers from the wafer surfaces or edges.
The configurable vacuum module 9502 may also include combinations of any of the above, as well as any other capabilities suitable for use between processing tools in a semiconductor manufacturing environment.
In general, it is expected that the configurable vacuum module 9502 may be configured at a fabrication site through the addition or removal of hardware associated with desired functions. Thus, for example, temperature sensors and a heating element may be removed, and replaced with multiple shelves for wafer storage. Other aspects, such as construction from materials appropriate for high vacuum, may be implemented during manufacture of the module 9502. In general, a configurable vacuum module 9502 as described herein is characterized by the removability/replaceability of module hardware, or by an adaptation to a particular process using a combination of hardware that provides multiple capabilities (e.g., heating, cooling, aligning, temperature sensing, cleaning, metrology, annealing, scanning, identifying, moving, storing, and so forth).
The functions described above may also be implemented directly within the cart and tunnel systems described above, either as link modules within a tunnel, or in association with a cart or tunnel, to provide various processing functions during transportation of a wafer. As described herein, combining work piece handling vacuum modules and carts/tunnels provides greater flexibility to a semiconductor processing system by facilitating the interconnection of local processing groups that are separated by a large distance, and by facilitating the interconnection of large processing systems that are in close proximity. Combining a multifunction module 9502 with a cart/tunnel system can facilitate the productive use of transport time to achieve more rapid wafer processing.
As shown in
A vacuum tunnel extension 9602 can also be used with load locks 14010 to create service access between vacuum modules. Two such examples illustrated in
A vacuum tunnel extension 9602 may be employed in a variety of other locations within a system. For example, a vacuum tunnel extension 9602 may be employed to connect a linear processing system, a cluster tool, a shared metrology system or an equipment front end module to a cart and tunnel transport system. A vacuum tunnel extension 9602 may facilitate forming various layout shapes of semiconductor processing systems, and may be provided in various extension lengths.
More generally any of the above systems may be used in combination. For example, a linear processing system including work piece transport, such as that provided by a work piece handling vacuum module combined with a transport cart 6140 may be associated with a bypass thermal adjuster. A work piece handling vacuum module may facilitate transfer of a work piece to/from the bypass thermal adjuster. A linear processing system including work piece transport, such as that provided by a work piece handling vacuum module combined with a transport cart 6140 may be associated with a wafer center finding method or system. A work piece handling vacuum module may facilitate collecting data of a work piece being handled by the work piece handling vacuum module to support the wafer center finding methods and systems. A work piece handling vacuum module may include a plurality of work piece sensors to support wafer center finding. Wafer center finding may also be performed while the work piece is being transported by the transport cart 6140. In one embodiment, a work piece handling vacuum module, adapted to facilitate wafer center finding, may be assembled to a transport cart 6140 so that a wafer/work piece held within the work piece handling vacuum module may be subjected to a wafer finding process during transport.
A linear processing system including work piece transport, such as that provided by a work piece handling vacuum module combined with a transport cart 6140 may be associated with a process chamber. A work piece handling vacuum module may facilitate transfer of a work piece to/from the process chamber. As herein described, processing chambers of various types, sizes, functionality, performance, type, and the like may be combined with one or more transport carts 6140 to facilitate processing flexibility of a semiconductor processing system. A linear processing system including work piece transport, such as that provided by a work piece handling vacuum module combined with a transport cart 6140 may be associated with a load lock 10410 as herein described. In an example a work piece handling vacuum module may facilitate transfer of a work piece between the load lock and a transport cart 6140. A linear processing system including work piece transport, such as that provided by a work piece handling vacuum module combined with a transport cart 6140 may be associated with a work piece storage and handling cassette. A work piece handling vacuum module may facilitate transfer of a work piece to/from the cassette as shown in
A linear processing system including work piece transport, such as that provided by a work piece handling vacuum module combined with a transport cart 6140 may be associated with an equipment front end module 6110. A work piece handling vacuum module may facilitate transfer of a work piece to/from the equipment front end module 6110. The work piece handling vacuum module may transfer one or more work pieces between two equipment front end modules 6110 wherein one module is an input module, and one module is an output module, or wherein one of the modules is a mid entry input/output module. A transport cart 6140 may be associated with an equipment front end module 6110 through a work piece handling vacuum module as shown in
A linear processing system including work piece transport, such as that provided by a work piece handling vacuum module combined with a transport cart 6140 may be associated with a work piece elevator. A work piece handling vacuum module may facilitate transfer of a work piece to/from the work piece elevator for transporting one or more work pieces between vertically separated work piece handling and/or processing systems. Vertically separated vacuum processing systems may include a processing level and a work piece return level that is vertically separated. The work piece return level may include a work piece transport cart or vehicle in a vacuum tunnel for transporting one or more work pieces to a different location in the vacuum processing system.
A linear processing system including work piece transport, such as that provided by a work piece handling vacuum module combined with a transport cart 6140 may be associated with a cluster system as shown in
The work piece handling vacuum module may be modularly connected to the cluster system so that the work piece handling vacuum module may provide handling of work pieces while the cluster processing system may provide processing of semiconductor work pieces. The work piece handling vacuum module may be connected to the cluster system through a buffer module, such as a multifunction module, a passive single work piece buffer, a passive multi work piece buffer, a thermal bypass adapter, a buffering aligner 9700, and the like. The buffer module may provide a temporary storage facility for work pieces being transferred between the work piece handling vacuum module and the cluster system. A robot controller of the cluster system may access or deposit a work piece in the buffer module for the work piece handling vacuum module to transfer. A plurality of cluster systems may be connected to one work piece handling vacuum module so that the work piece handling vacuum module facilitates transfer from one cluster system to another. Such a configuration may include a load lock 1401 and/or equipment front end module 6110 for exchange of the work pieces with an operator. The work piece handling vacuum module may further include facilities for determining a center of a work piece being handled by the work piece handling vacuum module so that the work piece can be transferred to the cluster system centered accurately to a center reference of the cluster system.
A linear processing system including work piece transport, such as that provided by a work piece handling vacuum module combined with a transport cart 6140 may be associated with other work piece handling vacuum modules. A work piece handling vacuum module may facilitate transfer of a work piece to/from the other work piece handling vacuum module.
A linear processing system including work piece transport, such as that provided by a work piece handling vacuum module combined with a transport cart 6140 may be associated with a buffer. A work piece handling vacuum module may facilitate transfer of a work piece to/from the buffer. The buffer may facilitate holding work pieces queued to be processed. The buffer may further facilitate reducing bottlenecks associated with robotic work piece handlers, differences in processing time, delays associated with vacuum environment changes, and the like.
A linear processing system including work piece transport, such as that provided by a work piece handling vacuum module combined with a transport cart 6140 may be associated with a controller. The controller may direct the work piece handling vacuum module to facilitate transfer of a work piece from a first section of a semiconductor processing system to a second section of the system. Transfer from the first to second section of the system may be accomplished by using a transport cart 6140. A section may include one or more of a buffer, a buffering aligner 9700, another work piece handling vacuum module, a cluster system, a work piece storage, a work piece elevator, an equipment front end module, a load lock, a process chamber, a vacuum tunnel extension, a module including a low particle vent, a module including a pedestal, a module including a modular utility supply facility, a bypass thermal adjuster, a multifunction module, a robot (e.g. single arm, dual arm, dual end effector, frog leg, and the like), variously shaped process systems, and the like.
The aligner vision system 9708 may sense a notch or other marking on the semiconductor work piece, and the controller may use the notch to determine a correct alignment of the work piece, such as by stopping rotation of the work piece when the notch is in a particular location. The aligner vision system 9708 may also employ optical character recognition (OCR) capabilities or other image processing techniques to read and record information presented on the semiconductor work piece, which may include alignment marks as well as textual information relating to the work piece. The controller may also, or instead, provide close-loop sense and control for the alignment of semiconductor work piece placed on the buffer aligner module 9700.
A linear processing system including work piece transport, such as that provided by a work piece handling vacuum module combined with a transport cart 6140 may be associated with a buffering aligner 9700. A work piece handling vacuum module may facilitate transfer of a work piece to/from the buffering aligner 9700 such as to/from an equipment front end module, load lock, and other semiconductor fabrication system modules, handlers, and processors. A buffering aligner 9700 may be beneficially combined with other elements of a linear processing system to improve throughput. In an example, a buffering aligner 9700 may be combined with a transport cart 6140 system that provides transport of a plurality of aligned wafers in a vacuum environment. A buffering aligner can be employed when a process chamber requires delivery of multiple wafers at the same time, in which case buffering at the alignment can significantly increase the system throughput by allowing the system to align wafers in the background during processing and effecting a batch transfer to the process module or load lock.
A robot drive mechanism 10120 may be integrated within the pedestal 10110. Integration of the robot drive mechanism 10120 into the support structure may advantageously eliminate the need for separate conduits or encasements to house the robot drive mechanism 10120. An access port 10125 within the pedestal 10110 may provide user access to various components of the robot drive 10120 such as motors, amplifiers, seals etc., so that these components can be removed as individual units for servicing and the like.
The pedestal configuration depicted in
The pedestal 10110 may include a rolling base 10130 (with adjustable stand-offs for relatively permanent installation) on which additional controls, or equipment 10140 may be included. The rolling base 10130 further facilitates integration of vacuum modules 6130 into a modular vacuum processing and handling system.
A linear processing system including work piece transport, such as that provided by a work piece handling vacuum module combined with a transport cart 6140 may be associated with a pedestal. A work piece handling vacuum module may be modularly mounted to the pedestal so that the pedestal may provide at least support for the work piece handling vacuum module. The pedestal may further support drive mechanism that provide rotation and other motion of a robotic work piece handler in the work piece handling vacuum module. The pedestal may be integrated with the work piece handling vacuum module as herein described. The pedestal may further facilitate supporting a work piece handling vacuum module in a position that facilitates transferring a work piece to a transport cart 6140 in a tunnel 6150.
Linking modules 10149 between the vacuum modules 6130 may provide any of the functions or tools described herein with reference to, for example, the configurable vacuum modules 9502 described above. This includes auxiliary equipment 10150 such as a vacuum pump, machine vision inspection tool, heating element, or the like, as well as various machine utilities (gas, electric, water, etc.) which may be removably and replaceably affixed in a vacuum or other functional seal to an opening 10155 in the linking module 10149.
Processing tools can connect to the work piece handling system 10200 at any one of the ports of one of the linkable modules 6130. By applying industry standards for utility hookup type and position in a process chamber, the position of the utility hookups outside the volume of the linking modules may be substantially predetermined based on the position of the linkable module(s) 6130. Due to the pedestal configuration, however, it is also possible to allocate the void space around each pedestal to ensure a buffer zone 10240, 10250, 10260 around the linking modules that affords substantially arbitrary routing of utilities throughout an installation using the linkable modules. The handling system 10200 enables a user to take advantage of modular utility delivery components 10240, 10250, and 10260 when preparing to install process chambers.
The buffer zones 10240, 10250, and 10260 facilitate delivery of utilities such as gas, water, and electricity to any process chambers connected to the linkable modules 6130. These buffer zones 10240, 10250, and 10260 may specifically accommodate positioning requirements of industry standards, and may also accommodate any industry standard requirements for capacity, interfacing, cleanliness, delivery pressure, and the like (without, of course, requiring conformity to these standards within the buffer zones).
Conceptually, the buffer zones 10240, 10250, and 10260 may have a structural frame which supports a plurality of conduits 10270 adequate for delivery of the corresponding utilities. Each conduit 10270 may be constructed with appropriate materials selected to meet the specific requirements for delivery of a specific utility, and may be arranged within the buffer zones in any preferred pattern. Additionally, each conduit device port hookup 10280, may be arrayed in a predetermined pattern (e.g. meeting industry standards for utility hookup position) to facilitate connections outside the buffer zones while ensuring alignment of utility conduits from module to module within the buffer zones.
Device port hookups 10280 may be selected for each utility type. For example, a hookup for water may provide reliable interconnect that can withstand water pressure, temperature, and flow rate requirements, while a hookup for electricity may provide a reliable interconnect or conduit that meets electrical impedance, safety, and current capacity requirements. In embodiments, the position of the device port hookups 10280 within the buffer zones may be mechanically identified and/or adjustable (e.g. by means of a flexible conduit).
In an embodiments, a physical device such as a foam mold or other structural frame containing hookups 10280 and conduits for various utilities in each buffer zone 10240, 10250, and 10260 may be provided as a kit, which may allow for a variety of configurations to meet installation needs such as height, width, position of conduit, position of device hookups, and frame mounting within the constraints of the corresponding standard(s).
In embodiments, the buffer zones 10240, 10250, 10260 may be fully customized to meet a specific user installation and operational needs. In such an embodiment the user may provide specifications covering aspects of the system such as height, width, position of conduit, position of device hookups, mounting method, and optional aspects such as enclosure, and base to a manufacturer.
In embodiments, the buffer zones 10240, 10250, and 10260 may be arranged with one or more of the conduits 10270 in predetermined patterns forming one or more standard layers for utilities, and one or more customizable layers. The standard layers for example, may be for water and electricity, while the customizable layers may be for gas. The standard layers may additionally incorporate predetermined conduits for water electrical wiring.
As shown in
In embodiments with differently shaped process chambers, such as a chamber that is wider in the isolation valve connection area than in the utility components connection area, the width of the buffer zones 10240 and 10260 may be different than the embodiment shown in
The embodiment shown in
In embodiments, the utility delivery components 10404, 10406, 10408 may include sensors for sensing aspects of each utility (e.g., fluid flow, gas flow, temperature, pressure, etc.) and may include a means of displaying the sensed aspects or transmitting sensor data to a controller or other data acquisition system. Sensors and associated displays may be useful for installation, setup, troubleshooting, monitoring, and so forth. For example, a modular utility delivery component 10404 delivering water may include a water pressure sensor, a water flow rate sensor, and/or a water temperature sensor, while a display may display the corresponding physical data. Other sensors for display or monitoring may include gas pressure, type, flow rate, electricity voltage, and current. Additionally, the sensors may transmit an externally detectable signal which may be monitored by a utility control computer system.
A linear processing system including work piece transport, such as that provided by a work piece handling vacuum module combined with a transport cart 6140 may be associated with a modular utility delivery component 10240 that may supply utilities such as air, water, gas, and electricity to a sections of a semiconductor processing system through modular connection. Groups of vacuum modules that are being provided utilities though the modular utility delivery component, such as process chambers 2002, multifunction modules 9702, bypass thermal adjusters 9402, work piece handling vacuum modules, one or more load locks 14010, wafer storage, and the like may be combined with a transport cart 6140 to facilitate transport of one or more work pieces between distal groups. Referring to
In general operation, the system 10500 seals in work pieces with a door 10501 that may be opened and closed using any of a variety of techniques known to one or ordinary skill in the art to isolate the interior 10502 from an exterior environment. In operation, the system opens and closes the door 10501 to the chamber 10502, opens the gas valve 10530 to supply gas to an interior 10502 of the system 10500, closes the gas valve 10530, and then evacuates the interior 10502 to form a vacuum for the work pieces 10510. Unloading the work pieces 10510 may be accomplished in a similar way except that the system 10500 begins with a vacuum environment and is pressurized by the gas flowing through the open gas line valve 10530 and the adapted gas line 10520.
Once the work pieces 10510 are placed in the interior 10502, venting and pumping may be performed. During this process, the particle filter 10540, configured in-line with the adapted gas line 10520 or across the opening of the chamber interior 10502, filters large particles being transported by the gas. In addition, the baffle 10550 and the adapted gas line 10520 combine to absorb the supersonic shock waves that result from releasing a vacuum seal for the interior 10502, thereby preventing or mitigating disruption of particles within the interior 10502.
The gas line, typically a cylindrical shaped tube for passing gas from the valve 10530 to the module, is adapted by modifying its shape to facilitate absorbing the supersonic shock wave. In one embodiment, the adapted gas line 10520 may be shaped similar to a firearm silencer, in that it may have inner wall surfaces that are angled relative to the normal line of travel of the gas. More generally, the gas line may include any irregular interior surfaces, preferably normal to a center axis of the gas line. Such surfaces disperse, cancel, and or absorb the energy of the supersonic shock wave (e.g., from releasing a vacuum seal).
To further reduce the impact of the supersonic shock wave, the baffle 10550 obstructs travel of any remaining shock wave and protects the work pieces 10510 from perturbations that might otherwise carry particle contamination. The baffle 10550 may be positioned to reflect incident portions of the supersonic shock wave, canceling some of its energy, resulting in a substantially reduced shock wave impacting surfaces throughout the interior which may have particles. The baffle 10550 may be larger than the opening, as large as the opening, or smaller than the opening, and may be generally displaced toward the interior of the chamber from the opening. In one embodiment, the baffle 10550 may be moveable, so that it may be selectively positioned to obstruct shockwaves or admit passage of workpieces.
A low particle vent system as described above may be deployed at any location within any of the above systems where a vacuum seal might be released or created.
Many of the above systems such as the multi-function modules, batch storage, and batch end effectors may be employed in combination with the highly modular systems described herein to preserve floor space and decrease processing time, particularly for processes that are complex, or for installations that are intended to accommodate several different processes within a single vacuum environment. A number of batch processing concepts, and in particular uses of a batch aligner, are now described in greater detail.
The front opening unified pods 10614 may store wafers in groups, such as four. While a four wafer system is provided for purposes of illustration, it will be understood that the system 10600 may also, or instead, be configured to accommodate groups of 2, 3, 4, 5, 6, or more wafers, or combinations of these, and all such groupings may be considered batches as that term is used herein.
An in-atmosphere robot 10612 may operate to retrieve groups of wafers from the FOUPs 10614 which generally manage atmospheric handling of wafers for processing in the system 10600. The robot 10612 may travel on a track, cart or other mechanism to access the FOUP's 10614, the load lock 10604, and the buffering aligner 10608. The robot may include a batch end effector for simultaneously handling a batch of wafers (or other workpieces. The robot 10612 may also, or instead, include dual arms or the like so that a first arm can pick and place between the FOUPs 10614 and the batch aligner 10608 while the other arm provides a batch end effector for batch transfers of the aligned wafers in the buffer 10608 to the batch load lock 10604 and from the load lock 10604 back to the FOUPs 10614.
The buffering aligner 10608 may accommodate a corresponding number of wafers (e.g., four) that are physically aligned during the buffering process. It will be understood that while a single buffering aligner is shown, a number of buffering aligners may be arranged around the in-atmosphere robot, or may be vertically stacked, in order to accommodate groups of batches for processing. It will also be understood that the buffering aligner 10608 may employ any active or passive techniques, or combinations of these, known to one of skill in the art to concurrently align two or more wafers for subsequent batch handling.
As a significant advantage, an aligned batch of wafers can be processed more quickly in batch form downstream. Thus, for example, an aligned batch of wafers can be transferred to the batch load lock 10604 by the robot 10612 in a manner that preserves alignment for transfer to the in vacuum robot 10610, which may include a dual arm and/or dual end effectors for batch handling of wafers within the vacuum. Further, the in-vacuum batch buffer 10606 may accommodate batches of wafers using, e.g., shelves or the like to preserve alignment during in vacuum buffering and/or hand off between robots. The batch buffer 10606 may, of course, provide cooling, temperature control storage, or any of the other functions described above that might be useful between processing modules in a semiconductor manufacturing process.
Using this robotic arm configuration, the single end effector 10704 may be employed for individual picks and placements of wafers within modules while the dual end effector 10708 may be employed for batch transfers between processing modules via, e.g., batch buffers 10606, robot-to-robot hand offs, or any other suitable batch processing technique.
It will be appreciated that numerous variations to this batch technique are possible. For example, the batch end effector may include two blades, three blades, or any other number of blades (or other suitable wafer supports) suitable for use in a batch process. At the same time, each robotic arm 10702, 10706 may be a multi-link SCARA arm, frog leg arm, or any other type of robot described herein. In addition, depending on particular deployments of manufacturing processes, the two arms may be fully independent, or partially or selectively dependent. All such variations are intended to fall within the scope of this disclosure. In addition to variations in batch size and robotic arm configurations, it will be understood that any number of batch processing modules may be employed. In addition, it may be efficient or useful under certain circumstances to have one or more non-batch or single wafer process modules incorporated into a system where process times are suitably proportional to provide acceptable utilization of the single and batch process modules in cooperation.
Having thus described several illustrative embodiments, it is to be appreciated that various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to form a part of this disclosure, and are intended to be within the spirit and scope of this disclosure. While some examples presented herein involve specific combinations of functions or structural elements, it should be understood that those functions and elements may be combined in other ways according to the present invention to accomplish the same or different objectives. In particular, acts, elements, and features discussed in connection with one embodiment are not intended to be excluded from similar or other roles in other embodiments. Accordingly, the foregoing description and attached drawings are by way of example only, and are not intended to be limiting.
The elements depicted in flow charts and block diagrams throughout the figures imply logical boundaries between the elements. However, according to software or hardware engineering practices, the depicted elements and the functions thereof may be implemented as parts of a monolithic software structure, as standalone software modules, or as modules that employ external routines, code, services, and so forth, or any combination of these, and all such implementations are within the scope of the present disclosure. Thus, while the foregoing drawings and description set forth functional aspects of the disclosed systems, no particular arrangement of software for implementing these functional aspects should be inferred from these descriptions unless explicitly stated or otherwise clear from the context.
Similarly, it will be appreciated that the various steps identified and described above may be varied, and that the order of steps may be adapted to particular applications of the techniques disclosed herein. All such variations and modifications are intended to fall within the scope of this disclosure. As such, the depiction and/or description of an order for various steps should not be understood to require a particular order of execution for those steps, unless required by a particular application, or explicitly stated or otherwise clear from the context.
The methods or processes described above, and steps thereof, may be realized in hardware, software, or any combination of these suitable for a particular application. The hardware may include a general-purpose computer and/or dedicated computing device. The processes may be realized in one or more microprocessors, microcontrollers, embedded microcontrollers, programmable digital signal processors or other programmable device, along with internal and/or external memory. The processes may also, or instead, be embodied in an application specific integrated circuit, a programmable gate array, programmable array logic, or any other device or combination of devices that may be configured to process electronic signals. It will further be appreciated that one or more of the processes may be realized as computer executable code created using a structured programming language such as C, an object oriented programming language such as C++, or any other high-level or low-level programming language (including assembly languages, hardware description languages, and database programming languages and technologies) that may be stored, compiled or interpreted to run on one of the above devices, as well as heterogeneous combinations of processors, processor architectures, or combinations of different hardware and software.
Thus, in one aspect, each method described above and combinations thereof may be embodied in computer executable code that, when executing on one or more computing devices, performs the steps thereof. In another aspect, the methods may be embodied in systems that perform the steps thereof, and may be distributed across devices in a number of ways, or all of the functionality may be integrated into a dedicated, standalone device or other hardware. In another aspect, means for performing the steps associated with the processes described above may include any of the hardware and/or software described above. All such permutations and combinations are intended to fall within the scope of the present disclosure.
While the invention has been disclosed in connection with the preferred embodiments shown and described in detail, various modifications and improvements thereon will become readily apparent to those skilled in the art. Accordingly, the spirit and scope of the present invention is not to be limited by the foregoing examples, but is to be understood in the broadest sense allowable by law.
All documents referenced herein are hereby incorporated by reference.