Substrate processing apparatus with vertically stacked load lock and substrate transport robot

A substrate processing apparatus substrate transport and load lock assembly comprising a first load lock, a first substrate elevator, and a transport robot. The substrate elevator has a first vertical drive and a first substrate support connected to the vertical drive. The support is vertically movable by the vertical drive along a path including a first position outside of the load lock and a second position inside the load lock. The transport robot has a movable arm for supporting at least one substrate thereon. The arm is movable into and out of the path while the support is located in the load lock.

BACKGROUND OF THE INVENTION
 1. Field of the Invention
 The present invention relates to processing of substrate and, more
 particularly, to an assembly of a vertically arranged load lock and
 substrate transport robot assembly.
 2. Prior Art
 U.S. Pat. Nos. 5,562,383 and 5,882,413 disclose different types of
 substrate processing apparatus. It is known in the art to provide a
 substrate transport robot between a station holding a cassette of
 substrates and a load lock into a main transfer chamber of the substrate
 processing apparatus. A problem with this type of arrangement is that the
 footprint is relatively large because the cassette holding station,
 substrate transport robot and load lock are arranged in series along a
 horizontal plane.
 SUMMARY OF THE INVENTION
 In accordance with one embodiment of the present invention a substrate
 processing apparatus substrate transport and load lock assembly is
 provided comprising a first load lock, a first substrate elevator, and a
 transport robot. The first substrate elevator has a first vertical drive
 and a first substrate support connected to the vertical drive. The support
 is vertically movable by the vertical drive along a path including a first
 position outside of the load lock and a second position inside the load
 lock. The transport robot has a movable arm for supporting at least one
 substrate thereon. The movable arm is movable into and out of the path of
 the substrate support while the support is located in the load lock.
 In accordance with another embodiment of the present invention a substrate
 processing apparatus substrate transport and load lock assembly is
 provided comprising a frame, a substrate elevator, and a transport. The
 frame has a first load lock chamber and a substrate pod receiving chamber
 vertically orientated relative to each other. The substrate elevator has a
 vertical drive and a first substrate support connected to the vertical
 drive. The support is vertically movable by the vertical drive between a
 position inside the first load lock chamber and a position inside the
 substrate pod receiving chamber. The transport has a movable arm for
 supporting a portable substrate pod thereon and for moving a portable
 substrate pod into and out of the substrate pod receiving chamber to
 transfer substrates between the substrate pod and the substrate support.
 In accordance with another embodiment of the present invention a substrate
 processing apparatus substrate transport and load lock assembly is
 provided comprising a frame, a first substrate elevator, and a substrate
 transport robot. The frame has a first load lock chamber and a substrate
 transport robot chamber vertically orientated one above the other. The
 first substrate elevator has a vertical drive and a first substrate
 support connected to the vertical drive. The support is vertically movable
 by the vertical drive between a position inside the load lock chamber and
 a position inside the substrate transport robot chamber. The substrate
 transport robot has a movable arm assembly and an end effector connected
 to the movable arm assembly. The end effector is sized and shaped to
 support at least one substrate thereon. The movable arm assembly is
 located in the substrate transfer robot chamber. When the substrate
 support is located in the load lock chamber the movable arm assembly is
 movable in an area of the substrate transport robot chamber vertically
 offset and aligned, at least partially, with the substrate support.
 In accordance with one method of the present invention a method of
 transporting substrates between a first load lock chamber and a portable
 substrate container is provided comprising steps of moving the substrates
 from the portable substrate container to a first substrate elevator. The
 substrate elevator having a first substrate support for directly
 individually supporting the substrates thereon, the substrate support
 being located in a receiving chamber vertically aligned with the load
 lock; and moving the substrate elevator to vertically move the substrate
 support from the receiving chamber into the load lock chamber, wherein the
 portable substrate container is directly connected to the receiving
 chamber while the substrates are moved from the container to the substrate
 elevator.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
 Referring to FIG. 1, there is shown a schematic top plan view of a
 substrate processing apparatus 10 incorporating features of the present
 invention. Although the present invention will be described with reference
 to the embodiments shown in the drawings, it should be understood that the
 present invention can be embodied in many alternate forms of embodiments.
 In addition, any suitable size, shape or type of elements or materials
 could be used.
 The apparatus 10 generally comprises a main transfer chamber 12, substrate
 processing modules 14, and a substrate transport and load lock assembly
 16. The chamber 12 is shown as having four sides, but in alternate
 embodiments the chamber could have any suitable shape with any suitable
 number of sides. The substrate processing modules 14 are well known in the
 art and are used for processing substrates such as semi-conductor wafers
 or flat panel display substrates. In this embodiment, the modules 14 are
 mounted to three sides of the chamber 12. In alternate embodiments the
 modules 14 could be mounted to more or less than three sides. The assembly
 16 is mounted to the fourth side of the chamber 12. In alternate
 embodiments more than one assembly 16 could be provided and, could be
 mounted to one or more sides of the main transfer chamber. Referring also
 to FIG. 2, the chamber 12 has a frame 18 and vertically spaced apertures
 20. The chamber 12 may be comprised of multiple chambers stacked or
 otherwise connected to each other; perhaps with a common frame or multiple
 frames. The processing modules 14 are mounted to the frame 18 at the
 apertures 20. Thus, vertical arrays or columns of modules 14 are attached
 to the frame 18. The chamber 12 also has a substrate transport robot 22
 (see FIG. 1) located, at least partially, inside the frame 18 for
 transporting substrates into, through and out of the frame 18. Any
 suitable type of robot could be provided in the chamber 12, but it needs
 to be vertically movable to pass through the vertically spaced apertures
 20. The chamber 12 could also have more than one robot located in main
 transfer area inside the frame 18. An example of one such robot is
 described in U.S. patent application Ser. No. 08/662,930, now U.S. Pat.
 No. 606,278 which is hereby incorporated by reference in its entirety.
 Although FIG. 2 shows columns of four apertures 20 on sides of the frame
 18, more or less apertures could be provided on each side, the apertures
 20 could be staggered on each side, and/or more than one column of
 apertures could be provided on a single side.
 Referring also to FIG. 3, the substrate transport and load lock assembly 16
 is connected to one side 24 of the frame 18. In this embodiment the side
 24 has two vertically spaced apertures 26, 28. The assembly 16 generally
 comprises a frame 30, a substrate elevator 32, and a transport 34. The
 frame 30 has two apertures aligned with the apertures 26, 28. Movable
 doors (not shown) can be provided at the apertures 26, 28 either connected
 to the frame 18 or the frame 30. The frame 30 has three stacked areas 36,
 37, 38. The top area 36 is located at the top aperture 26 and the bottom
 area 38 is located at the bottom aperture 28. In this embodiment the frame
 30 has a ledge 44 with an aperture 46 therethrough located between the top
 and middle area 36, 37. The frame 30 also has a ledge 48 with an aperture
 50 located between the middle and bottom areas 37, 38. The middle area 37
 has an aperture 40 on an opposite side of the frame 30 from the apertures
 26, 28. A movable door 42 is connected to the frame 30 for opening and
 closing the aperture 40.
 The substrate elevator 32 is similar to the elevator disclosed U.S. patent
 application Ser. No. 09/049,314, now Pat. No. 6,059,507 which is hereby
 incorporated by reference in its entirety. In this embodiment the elevator
 32 has two independently movable sections 52, 54. However, in an alternate
 embodiment a single elevator with multiple substrate receiving areas
 connected for unison vertical movement with each other could be used. The
 top elevator section 52 generally comprises a drive 56 and a substrate
 support 58. The substrate support 58 is adapted to separately support
 individual substrates thereon in a spaced configuration. The support 58 is
 connected to the drive 56 by a drive rod 60. The drive 56 can move the
 drive rod 60 vertically up and down to move the support 58 vertically up
 and down between positions in the top area 36 and the middle area 37. The
 top elevator section 52 also has two plates 62, 63 located on opposite top
 and bottom sides of the support 58. The top plate 62 makes a sealing
 engagement with a top side of the ledge 44 when the top elevator section
 52 is in a down position with the support 58 in the middle area 37. The
 bottom plate 63 makes a sealing engagement with an underside of the ledge
 44 when the top elevator section 52 is in an up position with the support
 58 in the top area 36. In one embodiment the drive 56 can also axially
 rotate the rod 60 and, thus, rotate the support 58 and substrates thereon.
 The bottom elevator section 54 generally comprises a drive 66 and a
 substrate support 68. The substrate support 68 is adapted to separately
 support individual substrates thereon in a spaced configuration. The
 support 68 is connected to the drive 66 by a drive rod 70. The drive 66
 can move the drive rod 70 vertically up and down to move the support 68
 vertically up and down between positions in the bottom area 38 and the
 middle area 37. The bottom elevator section 54 also has two plates 72, 73
 located on opposite top and bottom sides of the support 68. The top plate
 72 makes a sealing engagement with a top side of the ledge 48 when the
 bottom elevator section 54 is in a down position with the support 68 in
 the bottom area 38. The bottom plate 73 makes a sealing engagement with an
 underside of the ledge 48 when the bottom elevator section 54 is in an up
 position with the support 68 in the middle area 37. In one embodiment the
 drive 66 can also axially rotate the rod 70 and, thus, rotate the support
 68 and substrates thereon.
 The top area 36 and the bottom area 38 provide the function of being load
 lock chambers between the main chamber inside the frame 18 and the middle
 area 37. The top and bottom areas 36, 38 are preferably connected to a
 source of vacuum to evacuate air from inside the areas 36, 37. When the
 top substrate support 58 is in the top area 36 the robot 22 (see FIG. 1)
 can move substrates through the aperture 26 onto and off of the support
 58. When the bottom substrate support 68 is in the bottom area 38 the
 robot 22 can move substrates through the aperture 28 onto and off of the
 support 68. The middle area 37 forms a receiving area for loading
 substrates from a portable substrate container 74, also known as a carrier
 or pod, onto and off of the substrate supports 58, 68 when the supports
 58, 68 are located in the middle area 37. In a preferred embodiment the
 plates 63, 72 are larger than their respective related plates 62, 73 to
 take advantage of atmospheric pressure in the middle area 37 when the top
 and bottom areas 36, 38 have pressures less than atmospheric pressure to
 maintain seals at apertures 46, 50 by the plates 62, 73.
 Referring also to FIG. 4, an exploded perspective view of one embodiment of
 a portable substrate container 74 is shown. The container 74 has a main
 housing 76 and a removable side door 78. The container 74 is similar to
 that described in U.S. patent application Ser. No. 09/243,516, now Pat.
 No. 6,120,229 which is hereby incorporated by reference in its entirety.
 The container 74 is a FOUP (Front Opening Unified Pod) design for
 supporting and transporting a plurality of wafers in spaced relationship
 in a substantially particle free environment. The container 74 has a
 plurality of rack members 80 for supporting the wafers generally
 horizontally, in a generally vertically spaced relationship. At any one
 time, all or only some of the rack members 80 may actually be supporting
 wafers. In alternate embodiments other types of portable substrate holders
 could be used.
 The container 74 includes the housing 76 with a carrier port 82 for
 providing access to the interior 84 thereof. A carrier door 78 is
 removably connected to the housing 76 and is movable between a closed
 position overlying the carrier port 82 and an open position spaced from
 the carrier port 82. The carrier door 78 is illustrated as including a
 generally rectangular plate and has a peripherally extending continuous
 raised flange. A suitable seal 86 is interposed between the flange and the
 carrier port for sealing the interior of the carrier 74 from the
 surrounding atmosphere when the carrier door is in the closed position.
 For selectively locking the carrier door 78 in place overlying the carrier
 port 82 and with the flange firmly engaged with the seal 86, a plurality
 of latch members 88 are provided on the carrier door at peripherally
 spaced locations movable between an extended, locking position so as to be
 engaged with respectively positioned locking recesses 90 on the carrier
 adjacent the carrier port and a retracted release position disengaged from
 the locking recesses 90. Suitable keyway mechanisms externally indicated
 by latch keyways 92 are operably connected to the latch members 88 for
 moving the latch members between the locking position and the release
 position. The mechanisms (not shown) may be linkages or may be solenoid
 operated of may be of other appropriate design. In a typical manner, when
 the latch keyways 92 are vertically oriented the latch members 38 are
 extended such that the carrier door is closed and locked with the flange
 bearing firmly against the carrier port 82 with the seal 86 interposed
 between the flange and the port to maintain the particle free environment
 within the interior 84 of the carrier. When the latch keyways 92 are
 horizontally oriented the latch members 88 are retracted such that the
 carrier door is unlocked and capable of being removed from the carrier
 port 82. In this latter condition, the carrier door 78 is free to be
 removed from the carrier in a manner to be described below.
 Referring back to FIG. 3, the transport 34 generally comprises a carrier
 door opener 94, a support frame 96, a movable arm 98, and a drive 100 for
 moving the movable arm 98. The carrier door opener 94 is connected to the
 support frame 96 and is adapted to remove and replace the door 78 with the
 main housing 76 of the portable container 74 as described in U.S. patent
 application Ser. No. 09/243,516. The movable arm 98 is adapted to have the
 container 74 removably mounted thereon. The drive 100 is adapted to
 horizontally move the arm 94 to move the main housing 76 of the container
 74 relative to the support frame 96, as indicated by arrow A, through the
 aperture 40 into and out of the middle chamber 37 of the assembly 16. The
 drive 100 is preferably also able to slightly move the arm 98 vertically
 up and down when the main housing 76 is in the middle chamber 37 as
 indicated by arrow B. Of course, the movable door 42 must be out of the
 way of the aperture 40 for the arm 98 and main housing 76 of the container
 74 to move in and out of the middle chamber 37.
 The container 74, with substrates therein, is initially placed on the arm
 98 by an operator. The door 78 is then removed from the main housing 76 by
 the opener 94. The door 42 is opened and the arm 98 is moved to move the
 main housing 76 into the middle chamber 37. One of the substrate supports
 58 or 68 is located in the middle chamber 37 with plates 62, 72 or 63, 73
 sealing off the middle chamber 37 from top and bottom load lock chambers
 36, 38. The substrates S in the main housing 76 are moved into position
 over individual substrate support shelves 102 of the support 58 or 68. The
 substrates S are then vertically moved onto the shelves 102 off of the
 rack members 80 by merely moving the main housing 76 downward. The arm 98
 is then retracted back to the position shown in FIG. 3 to withdraw the
 main housing 76 from the middle chamber 37. The door 42 is moved to a
 closed position to close the aperture 40. The middle chamber 37 can be
 evacuated before moving the substrate support and substrates thereon. If
 the upper substrate support 58 was in the middle chamber 37, it is moved
 up into the upper load lock chamber 36 with the plate 63 being sealed
 against the ledge 44. The robot 22 (see FIG. 1) can then move the
 substrates from and to the support 58 while in the top load lock chamber
 36. If the lower substrate support 68 was in the middle chamber 37, it is
 moved down into the lower load lock chamber 38 with the plate 72 being
 sealed against the ledge 48. The robot 22 can then move the substrates
 from and to the support 68 while in the bottom load lock chamber 38.
 Once the unprocessed substrates are removed from the supports 58, 68 and
 replaced with processed substrates from the processing modules 14 (see
 FIG. 1) the supports 58, 68 can be separately returned to the middle
 chamber 37, the door 42 opened and the main housing 76 is inserted into
 the middle chamber 37 again by the arm 98. The main housing 76 is moved
 upward in the middle chamber 37 to remove the substrates from the shelves
 102 and now support the substrates on the rack members 80. The arm 98 is
 then moved to remove the main housing 76 from the middle chamber 37 with
 the processed substrates in the main housing 76. The door 42 is closed.
 The door 78 is replaced onto the main housing 76. The operator can now
 replace the container 74 with a new container of new substrates to be
 processed to repeat the process.
 With the present invention the footprint of the apparatus 10, when compared
 to prior art substrate processing apparatus, can be reduced. More
 specifically, the present invention allows the load lock chamber between
 the environment in the main transfer chamber 12 and the environment
 outside the chamber 12 to be vertically aligned, at least partially, with
 at least a portion of the robot(s) used to transfer the substrates from
 the initial portable substrate container placement area to the load lock
 chamber(s). In the prior art, such as disclosed in U.S. Pat. No. 5,512,320
 the robot in the atmospheric exchange section was located totally
 horizontally outward from the load locks. This increased the footprint of
 the processing apparatus. The present invention significantly reduces the
 size of the atmospheric exchange section by vertically stacking a part of
 the atmospheric exchange section with the load lock chamber(s) and
 vertically stacking a part of the robot of the atmospheric exchange
 section with the portable substrate container 74.
 FIG. 5 shows a schematic top plan view of an alternate embodiment of the
 transport 34'. The transport 34' has a frame 96', a carrier door opener
 94', three movable arms 98' each having a separate drive (not shown). The
 frame 96' is automatically or robotically movable relative to the assembly
 16 outside the clean room wall 104 as indicated by arrow C. This allows
 the containers 74 and arms 98' to be separately brought into registry with
 the door opener 94' and assembly 16 for interaction therewith. The two
 other areas not in registration with the door opener 94' and assembly 16
 can be used by the operator to load and unload the containers 74 on the
 arms 98'.
 FIG. 6 shows a schematic top plan view of another alternate embodiment of
 the transport 34". In this embodiment the transport has a frame 96", a
 carrier door opener 94" and two movable arms 98". The frame 96" can be
 rotated as indicated by arrows D to move the containers 74 into and out of
 registry with the door opener 94" for introduction of the containers 74
 into the assembly 16. In an alternate embodiment the transport 34" could
 have two lateral side carrier door openers at locations 95" wherein the
 containers 74 would be loaded on one of the movable arms 98" when the
 movable arm was located in a front position and the substrates and/or
 container moved into the assembly 16 when moved to either lateral side of
 the assembly 16.
 FIG. 7 shows a schematic top plan view of another alternate embodiment. In
 this embodiment the substrate processing apparatus has two assemblies 16
 attached to the main transfer chamber 12'. Each assembly 16 has its own
 transport 34 for moving separate containers 74 into and out of the
 separate assemblies 16.
 Referring now to FIG. 8 a schematic perspective view, similar to FIG. 2, of
 an alternate embodiment is shown. The frame 112 of the main transfer
 chamber 110 has three sides 114, 115, 116 with apertures 20 for mounting
 the substrate process modules 14 in vertically columns. The frame 112 also
 has two other sides 118, 119 having two assemblies 120 separately mounted
 to each side 118, 119. The assemblies 120 are substrate transport and load
 lock assemblies similar to the assemblies 16. However, the assemblies 120
 each only comprise one elevator section 122 rather than two elevator
 sections and one load lock chamber 124 rather than two load lock chambers.
 For each assembly 120, the transport 34 is able to move the container 74
 into and out of its receiving chamber 126. The drives 128 and respective
 substrate supports 130 are able to move the substrates between their
 respective chambers 124, 126.
 Referring now to FIG. 9, another alternate embodiment will be described. In
 this embodiment the substrate processing apparatus has a main transfer
 chamber 140 with two laterally spaced entrance apertures 142 (only one of
 which is shown). A door 144 is located at each aperture 142 for
 selectively sealing the aperture. A load lock chamber 146 is connected to
 the chamber 140 at each aperture 142. Each load lock chamber 146 has a
 bottom aperture 148 with a ledge 150. An elevator 152 is provided with
 each load lock chamber 146 having a drive 154 and a multi-substrate holder
 156 connected to the drive 154. The drive 154 is adapted to vertically
 move the holder 156 into and out of the chamber 146. The elevator 152 has
 a bottom plate 158 which can contact the ledge 150 to seal off the chamber
 140 when the elevator is in an up position. Located vertically spaced from
 the load lock chambers 146 is a robot 160 for moving substrates between
 the portable substrate container 74 and the substrate holders 156 when the
 holders are in a down position. One such robot is described in U.S. Pat.
 No. 5,720,590 and another in U.S. Pat. No. 5,431,529 which are hereby
 incorporated by reference. However, any suitable robot could be used.
 Referring also to FIG. 10, the portable container 74 is positioned on a
 frame 162. A door opener 164 is connected to the frame 162 to remove the
 door to the container 74. The main housing 76 remains stationary on the
 frame 162 as the robot 160 moves the substrates into and out of the main
 housing 76. The load lock chambers 146 and the drive 161 of the robot 160
 are contained in a same vertical plane which does not intersect the main
 transfer chamber 140 or containers 74. Thus, the footprint of the assembly
 146, 152, 160 and the horizontal distance between the containers 74 and
 entrance to the chamber 140 is smaller than in the prior art.
 FIGS. 11 and 12 show two different adaptations using this type of
 principle. In FIG. 11 the main transfer chamber 140 has two load lock
 chambers 146 attached to it. Each load lock chamber 146 has its own
 separate elevator section 152. The frame 162 includes a track section 166,
 and two container support areas 168. The containers 74 can be mounted on
 the support areas 168. Each support area 168 has a separate door opener
 164 associated therewith. The robot 160 is mounted on a car 170. The car
 170 is movably mounted on the track 166. A similar car/track configuration
 is disclosed in U.S. patent application Ser. No. 08/891,523, now U.S. Pat.
 No. 6,139,245 which is hereby incorporated by reference. However, any
 suitable horizontal traverse robot relocation system could be used. The
 robot 160 can move under the load lock chambers 146.
 In FIG. 12 the robot drive 161 is not moved from the relative position
 shown. Instead, the robot 160 uses a scara arm with an off-center pick
 technique similar to that described in U.S. patent application Ser. No.
 09/163,844 which is hereby incorporated by reference. The arms 163 of the
 robot 160, including the proximal or upper arm 165, can move under the
 load lock chambers 146.
 It should be understood that the foregoing description is only illustrative
 of the invention. Various alternatives and modifications can be devised by
 those skilled in the art without departing from the invention.
 Accordingly, the present invention is intended to embrace all such
 alternatives, modifications and variances which fall within the scope of
 the appended claims.