JP5388279B2 - Substrate transfer processing apparatus and method - Google Patents

Description

  The present invention generally relates to a novel substrate transfer processing apparatus and method, and more particularly to a wafer transfer processing apparatus and method.

  In semiconductor manufacturing, a common tool called a cluster tool is one of the important units used in wafer manufacturing. A typical commercial device has a generally circular central region, along which the chamber is mounted. Each chamber extends outward around the central region. As wafers are processed, each wafer is first moved from the I / O station on the outer periphery of the central chamber into the central chamber, and then moved from the central chamber into the attached or peripheral chamber for respective processing. Is done. With this tool, as with almost all manufacturing systems in use today, wafers are typically processed one at a time. After the wafer has been moved into the chamber for processing, it can be returned to the central chamber. Subsequently, after moving to another peripheral chamber, subsequent processing can be performed and returned to the central chamber. When the wafer processing is finally completed, the entire wafer is moved out of the tool. Such outward movement is similarly performed via an input / output station or chamber coupled to a vacuum system, and such processing is commonly referred to as “load lock”. In the load lock, the wafer is moved from a vacuum to an atmosphere (atmosphere). This type of unit is described in Patent Document 1, for example.

  In another tool, wafers are indexed along a central axis and fed through a surrounding processing chamber. With this tool, all wafers are fed simultaneously to the next processing stop. Each wafer can be processed independently, but cannot be moved independently. All wafers remain at the processing station for the same amount of time, but it goes without saying that the processing at each station can be controlled independently only for the maximum time allowed for each processing start point. The first described tool can be operated as described above, but in practice, each wafer does not move sequentially into the adjacent processing chamber, and not all wafers have a residence time in the processing chamber. The wafers can be moved so that they do not need to be the same.

  When any of the above systems are operating, the central region is typically located on the vacuum side, but may be located in some other preselected controlled environment or a predetermined controlled environment. In this central section there may be gases useful for processing performed, for example, in a processing chamber. The chamber or compartment along the outer surface of the central zone is also typically located on the vacuum side, but may have a preselected controlled gas environment. Processing is also performed in a vacuum, typically by moving a wafer in vacuum from a central chamber to an attached chamber or compartment. In general, when a wafer reaches a chamber or compartment for processing, the chamber or compartment is sealed off from the central chamber. This prevents the materials and / or gases used in the processing chamber or compartment from reaching the central zone, thus preventing contamination of the atmosphere in the central zone and the attached processing chamber and / or Contamination of a wafer waiting for processing or a wafer waiting for subsequent processing located in the central zone is prevented. This also allows the processing chamber to be set to a vacuum level that is different from the vacuum level used in the central chamber for the particular processing performed in the chamber. For example, if a chamber processing technique requires more vacuum, it should be in place between the central zone and the chamber to meet the processing requirements of a particular process performed within that chamber. A seal can be provided to further depressurize the chamber itself. On the other hand, if less vacuum is required, pressurization can be performed without affecting the pressure in the central chamber. After wafer processing is complete, the wafer is returned to the central chamber and then moved out of the system. In this manner, the wafer can be sequentially advanced through the chamber utilizing the tools described above and can receive all available processes. Alternatively, the wafer may only pass through selected chambers and receive only selected processing.

Various variations of the above processes are also used in equipment provided in the art. However, these variations tend to depend on the central region or central zone that is essential for the various processes. Also, since the primary use of such equipment is to make wafers, this specification primarily discusses wafers. However, it should be understood that most of the processes discussed herein are generally applicable to substrates, and that the teachings herein should be construed to apply to such substrates and manufacturing equipment as well. I want you to understand.
In recent years, systems have been described that differ from those described above in that they are linear rather than circular in shape and that the wafer moves from one chamber to the next for processing. Since the wafers move sequentially from one chamber to adjacent chambers, there is no need to provide a central zone as part of the equipment. With this tool, when a wafer enters the unit, it is typically attached to a chuck that moves with the wafer as it moves through the system. In this unit, the processing time performed in each chamber is the same.

  The footprint of this system is smaller than the typical footprint of the art because it approximates the footprint of the process chamber only and does not include a large central zone. This is the advantage of this type of equipment. This system is described in Patent Document 2. In this particular system, the residence time at each processing station is uniform. Of course, this allows some processing differences to be limited by the length of the longest residence time. Another approach may be preferred if the residence time needs to be controlled independently at various stations. This type of equipment also has the disadvantage that if one station goes down for repair or maintenance, the entire system becomes unusable for processing.

US Pat. No. 4,951,601 US Patent Application Publication No. 2006/0102078 A1

  The present invention is directed to a novel wafer processing unit that aims to maintain a small footprint and to control the residence time for each processing station individually. The present invention also allows ongoing operation even if one or more stations are down for one or other reasons. There is some recognition that the cost of manufacturing semiconductors is extremely high, and this cost is increasing. The higher the cost, the greater the risk when investing in this area. Its purpose is to define equipment that lowers costs by a reasonable percentage and to provide improved systems and services in accordance with “lean” manufacturing principles. Thus, an object of the present invention is to maximize the processing chamber while maintaining a small footprint. Another objective is to maximize the utilization of the processing station. Another object is to simplify robotics and service of this equipment. This system also provides considerable redundancy. It includes the possibility of using up to 100% of the processing system even during mainframe inspection. In such cases, fewer chambers are used, but all processes can continue to be used for wafer processing. The chamber can be inspected and processed from the back or front of the processing chamber. In addition, in a preferred embodiment, the processing chamber is prepared in a linear arrangement. This ensures a minimum footprint for a system that allows individual programs for wafers to be executed at various processing stations.

The processing chamber may generally have the ability to perform any of a variety of processes used in connection with wafer processing. For example, in wafer fabrication, the wafer is typically subjected to one or more etching steps, one or more sputtering or physical vapor deposition processes, ion implantation, chemical vapor deposition (CVD), and heating and / or cooling processes, among others. .

  The number of processing steps to make a wafer will require multiple tools, or tools with large subsystems, when using conventional equipment to perform these various processes. Can mean that. However, the system of the present invention has the additional advantage that additional functional stations can be added without a significant increase in size and without the need to add a new overall system. provide.

In order to achieve these various objectives, wafer transport is constructed to be independent of chamber design. For this reason, the chamber is designed to act as a chamber with a certain throughput. The transfer system is then configured to operate independently of the chamber design and is configured to supply wafers to or from the processing chamber.
The delivery of the preferred embodiment disclosed relies on a simple linkage arm that is based on linear / rotational motion through a vacuum wall.
In connection with keeping costs low, chamber design is based on modularity. Thus, in an embodiment, the system can have three chambers. Alternatively, a matching structure can be utilized and the system can have six chambers. Alternatively, this last sentence can be repeated for 4 or 8 chambers, or a plurality of others, or can be matched to modules having different numbers of processing stations.

The system is scalable and in addition can be extended independent of technologies that may be applied to future processes and applications. Linear wafer transport is used. As a result, a high throughput can be obtained in a system having a small area that does not exceed the size requirement of the clean room. In addition, different processing steps can be built on the same processing platform.
According to one aspect of the invention, a substrate processing system is disclosed. The system includes an elongated substrate transfer chamber having a vacuum part and an atmosphere part, a first linear track attached to the transfer chamber in the vacuum part, and a second linear track attached to the transfer chamber in the atmosphere part; A first base linearly mounted on the first linear track; a second base linearly mounted on the second linear track; and a magnetically coupled follower mounted on the first base as an input A speed reducer that provides a reduced rotational speed as an output, a rotary motor that is mounted on the second base and that rotates a magnetic driver that imparts rotational motion to the magnetically coupled follower via a vacuum wall; and A robot arm coupled to the output. A linear motor may be attached to the second base to provide linear motion, and a magnetizing wheel may be attached to the second base. A linear motion encoder may be coupled to the second base, and a rotary encoder may be coupled to the rotary motor. In a system having two robot arms, the arm extension may be coupled to one of the robot arms so that the rotation axes of the plurality of robot arms coincide.
According to another aspect of the invention, a method is provided for transporting a wafer through a vacuum transport chamber from a load lock to a processing chamber. This method provides a robot arm in a transfer chamber, magnetically couples linear motion to the robot arm via a vacuum wall, and magnetically couples rotary motion to the robot arm via a vacuum wall, The speed of the rotational motion is decelerated in the interior. The method further includes the following steps.
Determine that the first center point defined as the center of the wafer is located within the loadlock. Determine that the second center point defined as the center of the wafer is located within the processing chamber. Determine the position of the center of rotation of the arm. ・ Move the linear and rotational motion of the robot arm so that the wafer located on the robot arm moves only linearly between the load lock and the processing chamber. Calculate combinations

1 is a schematic diagram of a prior art cluster tool for PVD applications. FIG. FIG. 2 is a schematic diagram of the system described in the aforementioned US Patent Application Publication No. 2006/0102078 A1, and is a schematic diagram illustrating the nature of the prior art system. 1 is a schematic diagram of a processing system according to the present invention. FIG. 2 is a schematic top view showing the transfer chamber in more detail (in this figure, three processing stations are shown, but this number of stations is used for illustrative purposes only). 1 is a schematic diagram illustrating a portion of a system from a load lock to a transfer or transfer chamber. FIG. 2 is a schematic diagram of a wafer transfer mechanism shown outside a container for the system. 1 is a schematic diagram of a track drive system employed in a preferred embodiment. 2 illustrates an example of a linear motion assembly. FIG. 5A is a cross-sectional view taken along line AA of FIG. 4 and illustrates another example of a linear motion assembly. FIG. 3 is a cross-sectional view illustrating an example of a linear track in an atmosphere and a linear track in a vacuum. 6 illustrates another embodiment of an atmospheric linear track and a vacuum linear track. 1 is a schematic diagram of a 4-station physical vapor deposition (PVD) or sputtering system according to the present invention. FIG. 1 is a schematic diagram of an 8-station system according to the present invention. FIG. 1 is a schematic diagram of a 6-chamber system according to the present invention. FIG. Figure 2 is one of the schematic views of two different embodiments of the present invention. Figure 2 is one of the schematic views of two different embodiments of the present invention. An embodiment of an innovative mainframe system applied to a tandem-type processing chamber is shown. Figure 7 shows yet another embodiment of an innovative mainframe having a combination of different processing chambers. Figure 3 shows another embodiment in which different types of processing chambers are attached to a linear transfer chamber. Fig. 4 illustrates another embodiment in which an innovative mainframe is utilized for high throughput processing of substrates. Illustrates an embodiment in which two linear transport systems are stacked vertically. 3 illustrates an example of an innovative mainframe system in which induced current is used to power a robot arm.

  Referring now to FIG. 1, a cluster tool of the type commonly used today is shown. In general, the cluster tool includes processing chambers 21 that are radially disposed and attached to surround a central chamber 22. There are two central chambers in the system. It may be a chamber having only a single central chamber. If neglected, there may be systems with more than two central chambers, but the user will generally choose another system. In operation, a robot is typically placed in each central chamber 22. The robot receives the wafer into the system, transports the wafer from the central chamber to the processing chamber, and returns the wafer to the central chamber after processing is performed.

  In some prior art systems, the central robot can only access one wafer and one chamber at a time. Thus, the robot can become full or busy while the wafer is in a single chamber and the associated process is being performed. The throughput of this type of cluster tool is limited by the fact that there is only one robot and that such robot is constrained to a processing station during processing. More modern units use multi-arm robotics.

  The processing chamber may comprise any form of processor, such as a physical vapor deposition chamber, a chemical vapor deposition (CVD) chamber, an etching chamber, or other processes performed on the wafer during wafer fabrication. Chambers and the like. With this type of tool, the processing time can be varied. This is because when a wafer is processed, transfer to the chamber by the robot arm and removal of the wafer from the chamber are performed independently of other factors and are computer controlled. Needless to say, the processing can be set at the same time and in a defined order.

  Referring now to FIG. 2, a wafer processing tool is shown in which the wafer residence time in the chamber is the same for each chamber. In the present embodiment, the processors 23 are arranged in a straight line, and the chambers of this example are arranged adjacent to each other and on top of each other so as to overlap each other. At the ends of these chambers, there is an elevator that moves the wafer to be processed from one level to the other. The wafer enters from the inlet 26 and is placed on the support. The wafer remains on this support as it moves through the system. In one embodiment of the system, after the wafer has been raised to the upper level of the processor by the support, the wafer moves continuously through the processing chamber 23 at that level. The elevator 25 changes the level of the wafer, then moves along the other level, moves again from one processing chamber to the next, and so on, and then moves out of the system.

  Next, referring to FIG. 3, the processing chamber 31 is arranged linearly along the transfer chamber 32. The wafer enters the system 34 via an EFEM (Equipment Front End Module) 33 or some equivalent feed device. The EFEM 33 includes a station 30 in which a FOUP (from front opening unified pod) can be installed.

  A FOUP (not shown) includes a housing or housing in which a wafer is received and kept clean while waiting for processing operations. The EFEM 33 can also be associated with a feed mechanism. The feed mechanism is for placing the wafer in the system for processing, removing the wafer from the system after processing, and temporarily storing the wafer. Located on the EFEM 33 is a wafer FOUP where the wafer is lifted from the FOUP in the EFEM 33 and loaded into the load lock compartment 35 to place the wafer into the system. It is conveyed one by one.

  The wafer moves from the load lock compartment 35 along the transfer chamber 32 and is transferred from the transfer chamber 32 into the processing chamber 31. After entering the processing chamber, the substrate leaves the support arm and is instead placed on the substrate support in the chamber. At this point, the valve is closed to separate the atmosphere in the processing chamber and the atmosphere in the transfer chamber. This allows changes to be made inside the processing chamber without contaminating the transfer chamber or other processing chambers. After processing is performed, the valve that separates the processing chamber and the transfer chamber is opened, and the wafer is removed from the processing chamber and transferred to another processing chamber along the transfer chamber 32 for additional processing. Or is transferred to the load lock and returned from the load lock to the FOUP on the EFEM 33. In FIG. 3, four processing chambers 31 are shown.

  FIG. 3 also shows four processing power sources 37 and a power distribution unit 36. These are combined to provide the system electronics and provide power to each individual processing chamber. A process gas cabinet 38 and an information processing cabinet 40 exist on the processing chamber 31. Utilizing these units, information input to the system controls the movement of the substrate along the transfer chamber 32 and controls whether the substrate is transferred into the processing chamber for further processing. These units also provide a record of events that have occurred in the processing chamber. Gas used during processing in the chamber is supplied. Here, a robot operation mechanism for feeding a wafer between the system and each processing station in the system is described as a two-arm system. However, in reality, three or more arms may exist, The arms can be set to move independently within the transfer movement chamber or can be set to move together.

The processing chamber in the system can perform various processes as desired during wafer manufacturing. Today, many manufacturers purchase dedicated systems where the entire system is dedicated to sputtering or etching processes. In essence, there is a sufficient degree of sputtering or etching in wafer manufacturing that the entire system of four or more stages is dedicated to the sputtering process.
On the other hand, each wafer can be transported through a series of various processes required to reach the final process. For example, in the case of 5 processing stations, it is sufficiently assumed that the processing can be performed in the following order at the time of use. In the first processing station, the wafer is subjected to a degassing process, the second processing station is a pre-cleaning station, the third processing station is a sputtering station for depositing, for example, titanium, and the fourth processing station is a sputtering station for depositing, for example, nickel vanadium. In the fifth processing station, gold can be sputter deposited.

Referring now to FIG. 4, a three station system is shown with the top cover removed. The purpose of FIG. 4 is to enhance understanding of the transfer chamber 32. A wafer to be processed enters the system from the load lock 35 side. The load lock 35 is a dual level load lock and can process two wafers simultaneously. One is on the lower level and the other is on the upper level. Wafers that enter the system from the loadlock side enter a vacuum or controlled environment. Also, the processed wafers pass through the load lock 35 and move into the FOUP (not shown in FIG. 4) while they move away from the system and the vacuum or other controlled state within the system. Return to.
When the transition from the non-vacuum state to the vacuum state is completed, the wafer is lifted onto the arm 41 and the arm 41 moves into the transfer chamber 32. In FIG. 4, one such arm can be seen, the other arm being partially covered by the element on the left side of the first processing chamber. FIG. 4 shows a state in which the arm that can be entirely confirmed delivers a wafer into the processing chamber 31 (or a state in which a processed wafer is taken out from the chamber). The arm 41 moves on the straight rail 43 along the transfer chamber. In this embodiment, the rail in the transfer chamber 32 holds the support arm 41 above the floor surface of the chamber 32. Although not shown in FIG. 4, there is a drive mechanism that operates from the outside of the vacuum via the housing wall of the chamber 32. This drive mechanism allows for approximately linear as well as rotational movement of the arm 41 when it is desired to extend the arm 41 into the chamber or into the load lock 35.

Therefore, the arm is used to move the wafer in and out of the transfer chamber 32, in and out of the processing chamber 31, or in and out of the load lock chamber 35. By avoiding such contact with the base of the chamber, the generation of particles can be suppressed, and as a result, the environment can be kept cleaner or a particle-free state can be maintained.
In the following, further details of the transport system will be discussed with reference to the subsequent figures. Also, although two arms are shown in FIG. 4, the system can have more or less than three arms on the rail, and 3 at any given time. It will also be readily appreciated that more than one wafer transfer device can be handled.

  In accordance with the method of the present invention, the support arm 41 is operated using a combination of rotational and linear motion so that the wafer is moved only in a straight line. That is, as shown in FIG. 4, the arm 41 is moved using a combination of a linear motion exemplified by the double-headed arrow A and a rotational motion exemplified by the double-headed arrow B. However, the movement of the arm 41 is programmed so that the center of the wafer follows the linear motion indicated by the dashed lines BLl, BLm and BL. This allows any opening in the chamber 31 and load lock 35 to have a diameter that is slightly greater than the chamber diameter. Also, the combination of linear motion and arc motion of the arm 41 is actuated by a programmable controller, for example via the user interface UI (FIG. 3), according to any situation, so that any type and any combination of chambers Can also be mounted on the transfer chamber 32.

  In accordance with the method of the present invention, the following processing is performed to calculate the combination of linear and circular motion of the arm performed by the controller. The center position of the wafer when the wafer is placed in the load lock is determined. The center of the wafer is determined when the wafer is placed in each attached processing chamber. The pivot point of each arm is determined (note that the pivot points of both arms can be matched in some embodiments, as described below). A transfer sequence is determined, ie whether each wafer needs to move between the load lock and a single chamber or between the load lock and multiple chambers. These values can be programmed in the controller using the UI. The linear and rotational motion of each arm is then moved so that the wafers placed on each arm move only within a straight line between the determined pivot point and the center determined for the load lock and each chamber. Calculated.

  In one embodiment, in part, the following features of the present invention are implemented to simplify the combination of linear and arc motion of arm 41. In FIG. 4, one of the support arms 41, specifically, the arm 41 that is completely exposed in FIG. 4, is coupled to the arm extension 41 ′, and the other arm 41 is connected to the internal drive support mechanism 45 (see FIG. 4). 5 and also see FIG. 6). In the illustrated embodiment, the arm extension 41 ′ is fixed, that is, only follows the linear motion of the drive support mechanism 45, and cannot rotate. In other words, the rotational movement is only effected on the arm 41 secured to the end of the arm extension 41 '. Further, in the illustrated embodiment, the arm extension 41 ′ is configured so that the center of rotation of both arms 41, that is, the center of the turning center point can coincide with each other, that is, as illustrated, the straight broken line BLm is The arm 41 is fixed so as to pass through the center of the rotation point or pivot point. Furthermore, as shown in the embodiment of FIG. 5, the arm 41 can be moved in a linear direction so that the centers of rotation of both arms 41 are exactly aligned vertically. When such a design is used, the two arms 41 follow the combination of the same linear motion and arc motion from the same turning point center line, so that the arms 41 are manufactured in the same shape. It becomes possible.

  Referring now to FIG. 5, each part of the system 34 with the lid sealing the internal elements removed, i.e., the load lock 35, continues to the beginning of the transfer chamber 32 and continues to the first processing chamber 31. Each part including is shown. FIG. 5 shows a state in which the wafer 42 in the load lock 35 is placed on the arm 41. Another arm 41 is shown extending into the processing chamber 31. As shown, each arm 41 that works independently and can be located at different levels can be extended to enter different areas simultaneously. Each arm moves the wafer along the transfer chamber 32 from the load lock into the system 34 and then from the processing chamber around the system 34 to the processing chamber.

  Finally, after each wafer is processed, each arm moves them into the load lock 35 along the transfer chamber and then moves outside the system 34. When processing is complete, the wafer can be returned from the load lock into the FOUP where the processed wafer is collected. The wafer in the load lock or processing chamber is transported by lifting itself onto the support surface associated with arm 41. Lift pins on the support surface raise the wafer, allowing the arm to enter the lower part of the wafer, so that the arm can lift the wafer and move the wafer to the next step in the system. Become.

  Alternatively, slide down the wafer and use a structure that acts as a shelf to support the wafer during transport, supporting and holding the wafer when it is taken out or taken out of the chamber or compartment The wafer can be received from the arm and released from the arm. Each arm is arranged to pass above and below each other without contact, and can pass each other.

  Each arm is connected to an internal drive support mechanism 45. The drive support mechanism 45 is provided with a linear drive track, and the drive support mechanism 45 moves in the transport chamber 32 along the linear drive track. The operation of the drive support mechanism 45 is caused by an external drive source such as a motor. One form of drive source causes the drive support mechanism 45 to move linearly along the drive track 46. Another form of driving source rotates the arms 41 such that each arm 41 extends from the transfer chamber 32 into the load lock 35 or the processing chamber 31 in the process of moving the wafer 42 into and passing through the system. Inside the drive track 46 is an individual rail 47 (details are shown in FIG. 6) on which each drive support mechanism rests independently so that each arm 41 moves independently of each other. It can be arranged to act. The movement of the wafer into the processing chamber results in a parallel movement from the linear drive path into the chamber. This is because, in the preferred embodiment, the wafer experiences two modes of motion simultaneously. The wafer rotates as it moves linearly. By using an external motor or other form of drive mechanism to drive the mechanism in the vacuum of the transfer chamber 32, undesirable particles in the sealed vacuum region are reduced.

  Referring now to FIG. 6, the drive system utilized in the preferred embodiment of the present invention is shown. In FIG. 6, each rail 47 of the drive track 46 can be independently confirmed. In this figure, a wafer 42 is shown on one support arm 41. In this figure, the other support arm is shown in a state where it is simply extended. Each of the drive support mechanisms 45 is placed on one of the rails 47. Thereby, the arm 41 is easily arranged at various levels. A magnetic head or a magnetically coupled follower 48 is disposed at the base of each drive support mechanism 45.

  A magnetic drive source 50 is disposed at a position away from the magnetic head 48. The magnetic head 48 is placed in the vacuum of the transfer chamber, and the vacuum chamber wall (53 in FIG. 7A) passes below each magnetic head 48 and between the magnetic head 48 and the drive source 50. Therefore, the drive source 50 is outside the vacuum wall of the transfer chamber 32. As described above, the arm 41 moves the wafer 42 into the processing system and passes it through the processing system, and moves independently of each other. These arms 41 are driven by a magnetic coupler device including a drive source 50 and a magnetic head 48. This coupler provides both linear and rotational movement with respect to the arm 41. The drive source 50 is placed on the outer rail 51 that appears outside the vacuum and appears on both sides of the rail system. One rail set is shown in opposing relationship with another rail set appearing on the opposite side. The rotation of the arm is transmitted through the magnetic coupler and is driven by the rotary motor 52. In FIG. 6, although magnetic coupling is shown as being used for linear motion and rotation, it will be readily appreciated that separate magnetic couplers and drive sources can also be used. Thus, although linear and rotational motion is preferably transmitted through the same coupler, it is possible to use separate couplers for linear and rotational motion.

  One type of arm that can be used for wafer movement and manipulation, including stop motion at the processing station 31, is described as a selectively compliant articulated robotic arm, also referred to as SCARA robot for short. The SCARA systems tend to be faster and cleaner than Cartesian systems that are likely to be replaced by themselves.

  A repulsion magnet that reduces the attractive force generated by the motion coupling magnet may also be included to reduce and / or eliminate load factors associated with the magnetic drive system. Magnets that couple rotational and linear motion to a vacuum have a considerable attractive force. This is a load on the mechanical mechanism that supports the component. As the load increases, the life of the bearing is shortened and more particles are generated. By using repulsive magnets arranged in a magnetic coupler or separate device, the attractive force can be reduced. In practice, the innermost magnet in the magnetic coupler does not achieve a very high coupling stiffness. However, their inner magnets can be used to create repulsive forces with coupled magnets that are placed at NS pole locations that alternate around the diameter of the coupler and are used to attract each other.

  Of course, it should be understood that a drive mechanism can be included in the sealed chamber if there is no concern of particle dust entering the sealed chamber.

  Referring now to FIG. 7A, a side view of the track drive system with the lid removed is shown. In FIG. 7A, the vacuum wall or vacuum partition 53 is disposed at a position between the magnetic coupler 48 and the magnetic coupler 50 that drive and control the position of the arm 41. The drive track 46 houses a rail 47 that provides linear motion provided by the outer rail 51 to the drive support mechanism 45 and the arm 41. Rotational motion is provided by a rotary motor 52. In FIG. 7A, the side indicated by Va is in a vacuum, and the side indicated by AT is in an atmosphere. As shown in FIG. 7A, the magnetic coupler 50 is driven by a rotary motor 52 and directs the magnetic coupler 48 to perform the same rotational operation by magnetic coupling through the vacuum partition 53. On the other hand, the magnetic coupling hysteresis may cause the accuracy of the rotational motion of the arm to decrease.

  In practice, due to the length of the arm, a small angular error between the coupler 48 and the coupler 50 may greatly displace the wafer placed at the end of the arm 41. Also, transient motion may last for an unacceptable time due to the length and weight of the arm and due to the change in weight depending on whether the arm supports the wafer. In order to avoid these problems, a reduction gear (sometimes referred to as a reduction gear or a gear reduction gear) 55 is interposed between the magnetic coupler 48 and the rotary coupler 56 or the arm 41. The speed reducer is for reducing the operating speed given to the robot arm by power. The gear reducer 55 receives the rotation of the magnetic coupler 48, and the gear reducer 55 obtains a lower rotational speed output in order to operate the arm 41 at a rotational speed lower than the rotational speed of the motor 52. It is done. In this specific example, the reduction ratio of the gear reducer 55 is set to 50: 1. This greatly improves the accuracy of the angular arrangement of the arm 41, greatly reduces transient motion and greatly reduces the moment of inertia of the drive assembly technology.

  In FIG. 7A, the reduction gear assembly 55 is mounted on the base 49. The base 49 is non-motorized and can be freely placed on the straight rail 47. On the other hand, the rotary motor 52 is mounted on a base 54 that is placed on the straight rail 51 using mechanized power. Since the base 54 is moved linearly by the mechanized power, the magnetic coupling between the magnetic coupler 50 and the magnetic follower 48 provides a linear motion to the base 49 that is freely mounted on the linear rail 47, thereby causing the arm 41 to move linearly. Move. This device is therefore advantageous in that all motorized motion, i.e. linear motion and rotational motion, is performed under ambient conditions and there is no motor drive system in the vacuum environment. In the following, various embodiments relating to motor driven movement in atmosphere and free non-motor driven movement in vacuum will be described by way of example.

  FIG. 7B shows an example of a linear motion assembly. In FIG. 7B, a belt or chain drive source is coupled to the base 54. The belt or chain 58 is placed on a rotating body 59, and as indicated by an arrow C, one of the rotating bodies 59 is motor-driven so that it can move in both directions. In order to control the linear motion, the encoder 57a sends a signal identifying the linear motion of the base 54 to the controller. For example, the encoder 57a may be an optical encoder that reads the encoding provided on the linear track 46. Further, a rotary encoder 47b is provided on the motor 52, and the rotary encoder 47b transmits the encoding of the rotary motion to the controller. Using these read data for rotational and linear motion, the rotational and linear motion of arm 41 can be controlled so that the centerline of the wafer moves only within the straight line.

  7C is a cross-sectional view taken along line AA of FIG. 4 showing another embodiment of a linear motion assembly. In FIG. 7D, the drive track 46 supports the rail 47, and wheels 61 and 62 are placed on the rail 47. These wheels can improve traction by being magnetized. The wheels 61 and 62 are coupled to the base portion 54, and the rotary motor 52 is mounted on the base portion 54. A linear motor 63 that interacts with a series of magnets 64 mounted on the drive track 46 is attached to the lower portion of the base 54. The linear motor 63 interacts with the magnet 64 to bring the linear power toward the inside and outside of the drawing sheet to the base 54. The linear motion of the base 54 is monitored and reported by an encoder 57b that reads a position / motion encoding 57c provided on the track 46. In this specific example, the accuracy of the encoder 57b is 1 / 5,000th of an inch.

  FIG. 7D is a cross-sectional view illustrating an example of a straight track in an atmosphere and a straight track in a vacuum. The vacuum side and the atmosphere side are separated by a vacuum partition wall 53 and a chamber wall 32 interposed therebetween. On the atmosphere side, the rider 61 is placed on the straight track 47. Since this is in the atmosphere, the generation of particles is not as important as the vacuum side. Therefore, the rider 61 may include a wheel or may be made of a sliding material such as a fluororesin. The base 54 is attached to the slider 61 and supports a rotary motor that rotates the magnetic coupler 50. On the vacuum side, a linear track 78 is adapted to receive a sliding bearing 73 attached to the base 70 via a coupler 72. The straight track 78 can be made of stainless steel and is manufactured to minimize particle generation. In addition, lids 74 and 76 are provided to keep the generated particles within the bearing assembly. Base 70 extends beyond the bearing assembly and supports a gear reducer 55 coupled to magnetic follower 48.

  FIG. 7E shows another example of a straight track in the atmosphere and a straight track in vacuum. In FIG. 7E, the atmosphere side can be constructed similar to that of FIG. 7D. On the other hand, on the vacuum side, magnetic levitation is used instead of sliding bearings to minimize contamination. As shown in FIG. 7E, the electromagnetic assembly 80 in the active state cooperates with the permanent magnet 82 to form magnetic levitation, allowing free linear movement of the base 70. In particular, the permanent magnet 82 maintains the free space 84 and is not in contact with the electromagnetic assembly 80. As the base 54 moves linearly with the slider 61, the magnetic coupling between the coupler 50 and the follower 48 provides a linear motion of the levitated base 70. Similarly, the follower 48 is rotated by the rotation of the coupler 50, and this rotation is transmitted to the gear reducer 55.

  Referring now to FIG. 8, a processing system according to the present invention is shown. As in the case of FIG. 3, the EFEM 33 receives and receives a wafer that is passed to a system 34 that includes a processing chamber 31. In the present embodiment, the processing chamber 31 exemplifies a chamber in which sputter deposition is performed by first transferring a wafer to the load lock 35 and then transferring the wafer along the transfer chamber 32. The processed wafer is then fed along the transfer chamber 32 to the load lock 35 and then to the outside of the system and returned to the EFEM 33.

  Referring now to FIG. 9, an eight station processing system according to the present invention is shown. The EFEM 33 feeds the wafer to the load lock 35. The wafer is then moved along the transfer chamber 32 from the transfer chamber 32 to the processing chamber 31. In FIG. 9, both transfer chamber sets are arranged in the central region, and the respective processing chambers 31 are arranged outside thereof. In FIG. 10, all processing sections are aligned so that one processing chamber set is a duplicate of the next processing chamber set. Thus, the processing chambers of this system appear to be aligned in parallel.

  Of course, other variations are possible and will be readily envisaged. For example, instead of arranging the processing chambers in the form shown in FIG. 9 and FIG. When each set is arranged in sequence, each set is arranged so that the second set is arranged in a row following the first set, or the second set forms an angle with the first set. And can be aligned so that they can be set. Since the transfer chamber can feed wafers to the chamber on each side, two sets of processors can be set around a single transfer chamber and can be fed by the same transfer chamber (FIG. 11A). Reference: Each reference number in FIG. 11A indicates elements similar to those discussed with respect to the previous drawings).

  11A and 11B show a state in which the processing chamber 31 and the transfer chamber 32 are separated by the valve 39 as described above). If a second set of processors is connected to the first set of processors, it may be beneficial to place additional load locks along the system. Needless to say, it is also possible to add an EFEM to the end portion and place a load lock in front of the EFEM so that the wafer can move linearly and enter from one side (see FIG. 11B). Each reference numeral in FIG. 11B indicates the same elements as those in the previous drawings). In the latter case, the wafer can be programmed to enter and exit from one side or both sides. The processing chambers can be arranged at irregular intervals along the transfer chamber, that is, with a space between the processing chambers. An important feature of this arrangement is that each processing chamber is arranged so that the transfer chambers can feed the wafers to the individual processing chambers in the desired form and in response to computer-controlled commands for the system. .

In the known example, one having a tandem processing chamber is known. Each of the processing chambers is configured to process two side-by-side wafers. However, these known systems have a main frame and a robot configured to load two wafers that are always at a predetermined distance from each other. That is, the two arms of the known series loading robot cannot be controlled independently, and are installed at a fixed distance from each other. Therefore, the configuration of the main frame, the load lock, and the chamber is limited to a stack of two wafers separated by the same distance.
In addition, care must be taken to ensure that everything in the system, such as load locks, robot arms, chamber chucks, etc., are adjusted to be at exactly the same distance. This is a tremendous limitation and burden in system design, operation and maintenance.

  This innovative mainframe system is easy to configure to mount in-line chambers with increased design freedom and reduces the need for adjustment and maintenance. FIG. 12 shows an embodiment of an innovative mainframe system applied to an in-line processing chamber. The main frame includes a linear transfer chamber 1232. The linear transfer chamber 1232 includes robot arms 1241 and 1243 that move independently from each other, and a single-layer load lock chamber 1235. To illustrate the versatility of this innovative mainframe (one stack in this example), in this example a single layer or non-series load lock chamber 1235 is shown. In particular, unlike the prior art where the mainframe designed as a series chamber must have a series loadlock, here the robot arm is operated independently, so a single layer loadlock is connected in series. Wafers can be loaded onto multiple processing chambers of the mold.

  For example, two wafers can be placed one above the other inside the load lock 1235, with one arm taking the lower wafer and the other arm taking the upper wafer. Each arm places its wafer on one side of a series chamber. According to the innovative features of this embodiment, each robot can place the substrate on either side of the serial processing chamber. That is, unlike the conventional technique in which there is a one-to-one correspondence between the robot arm and the chamber, in other words, unlike the conventional technique in which the right robot arm can be carried only to the right side of the series-type chamber, Any arm can carry into either side of the series chamber.

In the example of FIG. 12, five chambers 1201, 1203, 1205, 1207 and 1209 are mounted on the upper part of the transfer chamber 1232.
Each of the chambers 1201, 1203, 1205 forms a series-type chamber configured to process two substrates simultaneously. Chambers 1201 and 1205 are shown with the top cover in place, while chamber 1203 is shown with the top cover removed. One advantage of this innovative mainframe is that the pitch (ie, center-to-center distance) of each serial processing chamber need not match that of the other. For example, the pitch of chamber 1205 shown as distance X need not be the same as the pitch of chamber 1203 shown as distance Y. Rather, each robot can be “trained” to know the center of each processing area of each chamber placed on the mainframe. As a result, each robot arm can distribute the wafer to any processing area and can be accurately centered.

  In addition, a single valve in the prior art system must be provided for the in-line chamber and load lock. In contrast, in the present invention, since the robot arm is independent, each process region can have its own independent isolation valve, as shown at 1251 and 1253 for the chamber 1201. Alternatively, a single valve may be used, as shown at 1255 for chamber 1203.

One advantage of using a serial chamber is that resources can be shared by two serial processing zones. For example, the two processing zones of the chamber 1201 share a processing gas source 1210 and a vacuum pump 1212. That is, each processing zone has its own gas distribution mechanism 1214, 1216 (eg, a showerhead and associated elements), while the gas distribution mechanisms of the two processing zones have the same gas supply 1210 (eg, gas To the stick).
The vacuum pump 1212 can be connected to an exhaust manifold leading to both processing zones. Thereby, both zones are maintained at the same pressure.
Other elements, such as RF elements, may be common to both processing zones, or may be provided separately for each zone.

Chambers 1207 and 1209 form a combined single-series processing chamber. That is, each of the chambers 1207 and 1209 is configured to process a single wafer. However, some features of the serial processing chamber are realized in this embodiment. For example, the processing gas supply source 1211 and the vacuum pump 1213 may be common to both chambers. The gas source and bias energy can be supplied from the same or separate sources.
Further, optionally, a key 1202 may be provided so that the two chambers are arranged and arranged while being mounted on the main frame to function as a normal series chamber. This does not involve the complexity and cost of manufacturing a larger serial processing chamber.

  FIG. 13 further illustrates an innovative mainframe with two series chambers 1301 and 1305, two independent single wafer chambers 1303 and 1304, and one composite single-series chamber 1307, 1309. Another embodiment is illustrated. That is, using the innovative mainframe 1332 where the robots 1341 and 1343 are independent can eliminate the need to ensure that the pitch is the same in all chambers. Therefore, a series chamber having the same pitch, a series chamber having different pitches, and a single wafer chamber can be mixed. Since the robots 1341 and 1343 can be handed over to each other, they can be loaded into each of the series chambers simultaneously. Also, they can be loaded into each of a plurality of single wafer chambers independently or in parallel, thus eliminating the need for utilizing complex series chambers and thus increasing the throughput of the chamber arrangement. Can be increased.

  Another feature illustrated in FIG. 13 is the use of a single central shut-off valve 1357 for loading into the in-line chamber 1305. As shown, valve 1357 is sized to allow only a single wafer to pass through. However, the two wafers are set in a series chamber 1305 as indicated by the curved arrows. This is not possible with prior art systems.

FIG. 14 illustrates another embodiment in which different types of processing chambers are attached to the linear transfer chamber 1432. In this example, a multi-wafer processing chamber 1405, a triple series chamber 1401, a single chamber 1404, a combined single-series chamber 1407 and 1409 are attached to the innovative mainframe.
Chamber 1405 may be a conventional batch processing chamber (eg, a thermal or plasma enhanced CVD chamber having four wafer stations (four circular arrays of processing regions defined therein)). Only one station may be loaded at a time, or two stations may be loaded.
The single chamber 1404 may be a single substrate processing chamber or a stacked multiple wafer cooling station. For example, a cooling station in which 25 wafers are stacked may be used.

Furthermore, since the robot arm is independent in the present invention, the series processing is not limited to processing two wafers at a time. In this example, a three substrate serial processing chamber is shown, allowing parallel processing of three wafers.
Here, only two arms are shown, and one arm needs to move twice to fully load the chamber 1401, while two or more arms as shown in FIG. It is also possible to use a device having

  Another optional feature shown in FIG. 14 is the use of robotic legs 1441, 1443, commonly referred to as SCARA (Selective Compliance Assembly Robot Arm). The robot arms 1441 and 1443 are mounted on linear rails as in the other embodiments of the present invention.

The embodiment of FIG. 14 also utilizes a series / stacked load lock chamber 1435. The load lock chamber 1435 has two wafers side by side.
While the load lock 1435 may be a conventional in-line load lock, the innovative mainframe allows the load lock to be given features that were not previously available. For example, by having a threshold 1438 while the load lock is in series, the load lock can be composed of two separate chambers. Two isolation gates 1437 and 1439 can also be provided (for each series wafer). With such a configuration, in the present invention, one gate can be opened and closed independently of the other gate. In this regard, the prior art differs from the present invention in that only a single gate is used and both sides of the series loadlock are opened together. In this way, both shut-off valves can be opened when the robot loads two wafers simultaneously. However, when a single wafer is loaded, only a single isolation gate needs to be opened.

FIG. 15 illustrates another embodiment in which the innovative mainframe is utilized for high throughput processing of substrates. This apparatus is useful when the processing of a substrate is repeated at a high throughput (for example, substrate processing for manufacturing a solar cell).
In this example, two linear rails 1543 and 1543 ′ are located in the transfer chamber 1532. Each supports two linear robot arms 1541. In one example, the robot arm on the linear track 1543 supplies the processing chamber 1501 on the left side of the transfer chamber 1532 while the other robot arm supplies the chamber on the other side. However, the robotic arm can be configured to supply either side of the transfer chamber 1532.

Another optional feature of the embodiment of FIG. 15 is the provision of two load locks. A load lock 1535 is used to load a substrate for processing. On the other hand, the load lock 1537 is used to lower the substrate after the processing is completed.
In this example, a series load lock is illustrated, but it should be understood that a single substrate load lock or a stacked load lock may be used as well.
By having an unloading load lock on the side opposite the loading load lock, other systems can be connected directly to the loading load lock, as indicated by the dashed silhouette, if desired. In this way, the system can be modularized to include various numbers of processing chambers as needed depending on the particular situation.

According to another embodiment of the invention, the innovative mainframe is laminated. As shown in FIG. 16, the upper linear transfer chamber 1633 is above the lower linear transfer chamber 1632. Each linear transfer chamber has a plurality of openings 1601 with suitable attachment devices for connecting the processing chambers.
The elevator 1662 moves the substrate between the upper and lower linear transfer chambers. In this particular example, the substrate is loaded from loading chamber 1671 and removed via unloading chamber 1673. However, if necessary, other elevators can be provided in front of the system as well. As a result, the chamber is loaded and lowered at the same level.

FIG. 17 illustrates an embodiment of an innovative mainframe system in which the induced current is used to provide a starting force to the robot arm. This example is similar to the example shown in FIG. 7D, but with one major difference. That is, in the above-described embodiment, the magnetic force is used to give linear and rotational motion to the robot arm. However, in this embodiment, the induced current is used to provide the starting force. For example, the robot arm assembly can include a stepper motor for rotational motion, for linear motion, or for performing both rotational and linear motion. In this embodiment, the stepper motor is energized using an induced current to avoid routing electrical wiring in the vacuum portion of the transfer chamber. Each of the stepper motors is located in a vacuum environment and is coupled to a conductive coil (eg, coil 48).

  The drive coil 50 is located outside the vacuum environment at a position facing the coil 48. When the stepper motor needs to be energized, current is passed through the appropriate coil 50. This coil 50 induces a current in the corresponding coil 48. And this energizes a motor.

  Although the chamber has been described as being in a vacuum, in practice, in some cases, the chamber may be provided in an area containing a particular gas or other fluid. Thus, the term “vacuum” as used herein should also be interpreted as a self contained environment, including for example a special gas that can be employed in the overall system.

In FIG. 1, the cluster tool includes seven processing chambers. In FIG. 9, the disclosed system includes eight processing chambers. The total installation area of the tool and peripheral equipment of FIG. 1 is about 38 m ² . The total footprint of the tool of FIG. 9 (and additional processing chambers and peripherals) is 23 m ² . Therefore, if the linear arrangement according to the present invention is used, the installation area of the system is considerably reduced even when the number of chambers is increased. For the most part, such improvements are achieved when utilizing an improved feed system, shown as transfer chamber 32 in FIG. 9, rather than using a central section associated with a system of the type shown in FIG. The

  The linear architecture of the present invention is extremely flexible and accommodates multiple substrate sizes and shapes. Wafers used for semiconductor fabrication are typically circular and have a diameter of 200 or 300 mm. In the semiconductor industry, attempts are constantly being made to increase the number of devices per wafer, and the wafer size has steadily increased to 75 mm, 100 mm, 200 mm, and 300 mm, and efforts aimed at wafers with a diameter of 450 mm continue. It has been. With the architecture unique to the present invention, the floor space required in a clean room wafer manufacturing plant is not as large as with typical cluster tools where each process is located in the vicinity.

  In addition, if it is desired to increase the size of this type (FIG. 1) of cluster tools to increase power, the overall dimensions will increase exponentially, while the system described herein is unidirectional Increase in size, i.e. the width of the system is the same and the length is only increased. In a similar process such as aluminum processing, the apparatus of FIG. 9 is similar to the apparatus shown in FIG. 9 in terms of throughput when the system of the type shown in FIG. Produces approximately twice as many wafers (approximately 170% increase) as the system shown in FIG. Thus, using the system disclosed herein, the measured wafer power per clean room area is greatly improved compared to prior art units. As a result, it goes without saying that the purpose of cost reduction during wafer manufacture is achieved.

  The design of this device is not limited to circular substrates. A cluster tool that moves a wafer in a circular path is particularly advantageous when the substrate is rectangular and the tool needs to be sized to handle a circular substrate inscribed in the rectangular shape of the actual substrate. On the other hand, the linear tool may be smaller than the size required to pass the actual shape in either direction. For example, when processing a 300 mm square substrate, the cluster tool needs to be sized to handle a 424 mm circular substrate, while the linear tool may be smaller than the size required for a 300 mm circular substrate.

  The size of the transfer chamber 32 is also a space necessary for moving a substrate that passes through the entrance chamber and enters the processing chamber and is moved from the processing chamber to the outside of the system. You just have to provide it. Therefore, the width of this chamber is only slightly larger than the size of the substrate being processed. However, smaller members can be processed in the system, or multiple members can be processed together at the substrate holder.

  Although the invention has been described with reference to specific embodiments having specific materials and specific steps, it should be understood by those skilled in the art that these specific examples can be modified or used. Such structures and methods are then discussed in terms of the practices described and illustrated, and operations that facilitate modifications that may be made without departing from the scope of the present invention as defined by the appended claims. It will also be appreciated by those skilled in the art that the resulting understanding will be obtained.

Claims (12)

A substrate processing system,
A transfer chamber for an elongated substrate;
A linear track added in the transfer chamber;
At least two robot arms mounted linearly on the linear track;
A connection disposed on a wall of the elongated substrate transfer chamber and configured to connect at least one multi-substrate processing chamber to the elongated substrate transfer chamber ; and
The multi-substrate processing chamber has a plurality of processing regions defined therein,
The connecting portion provides access to each of the plurality of processing regions, and each of the at least two robot arms is independently operable along the linear track, whereby each robot arm Independently access different processing areas,
Each of the robot arms is a substrate processing system having a structure in which a substrate is loaded in an arbitrary processing region of the multiple substrate processing chamber. The substrate processing system according to claim 1, further comprising a single layer load lock chamber.   The substrate processing system according to claim 1, further comprising a series-type stacked load lock chamber.   The substrate processing system according to claim 1, wherein the multi-substrate processing chamber has a single chamber body having a plurality of processing regions defined therein and arranged linearly. The multi-substrate processing chamber includes two chamber bodies mounted in alignment with each other, each of the two chamber bodies having a single processing region defined therein;
Furthermore,
The substrate processing system according to claim 1, wherein the two chamber bodies share at least one of a processing gas supply unit and a vacuum pump. The substrate processing system according to claim 1, wherein the multi-substrate processing chamber has a single chamber body, and the single chamber body has a plurality of circularly arranged processing regions defined therein. The substrate processing system according to claim 1, wherein at least one of the robot arms includes a SCARA robot arm. The substrate processing system according to claim 1, further comprising a load lock for loading and unloading connected to the transfer chamber for the elongated substrate on a side opposite to the load lock. The substrate processing system according to claim 8, wherein the loading / unloading load lock is configured to be attached to two linear transfer chambers simultaneously. The substrate processing system of claim 1, further comprising a second linear track having at least one robot arm mounted linearly. The substrate processing system according to claim 1, further comprising a multiple substrate cooling station mounted on the transfer chamber for the elongated substrate . An upper linear transfer chamber mounted on the elongate substrate transfer chamber ;
The substrate processing system according to claim 1, further comprising an elevator coupled to the elongated substrate transfer chamber and the upper linear transfer chamber and configured to transfer a substrate therebetween.

Images