JPS6342142A - Wafer handling arm - Google Patents

Abstract

(57) [Abstract] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a robot arm suitable for use in modular semiconductor wafer processing equipment.

[Background of the invention]

In the prior art, robot arms intended to handle wafers had parts that slid or interlocked with each other, thus creating dust.

[Purpose of the invention]

It is an object of the present invention to provide a robot arm for handling wafers in a vacuum that eliminates parts sliding relative to each other.

Another object of the invention is to provide a robotic arm in which the holding end of the arm follows a substantially straight path over a significant portion of the stroke of the arm.

[Summary of the invention]

A two-piece robot arm uses a specially shaped cam. As the arm moves on its cam, the drive cable is unwound and unwound, thereby removing the sliding belt and gears.

The robot arm includes a first arm and a second arm rotatably attached to the first arm. The holding end of the second arm follows a generally straight path for a significant portion of its stroke as the first arm rotates on the fixed cam.

These and other structural and operational features of the invention include:
It will become clearer from the following description of a preferred embodiment with reference to the drawing, which illustrates, by way of non-limiting example, one preferred embodiment and variant.

[Description of preferred embodiment]

Referring to the drawings, reference numerals are used to designate parts throughout the various views. FIG. 1 shows a partial schematic plan view of one embodiment of a modular semiconductor wafer transport and processing apparatus 1 according to the present invention.

Modular wafer processing device 1tri, wafer handler and hero lock module 400, Kate pulp module 100a-f, transfer modules 200a and 200b, processing module: x--/l/ 300a-300
d as well as a transit module 500 connected between transfer modules 200a and 200b.

The wafer handler and load lock module 400 is approximately rectangular in plan view, and the load lock chamber 40 is approximately rectangular in plan view.
6 and within the module 400 is at atmospheric pressure. A controlled low particulate atmospheric environment is provided in this part of the device. In operation, selected wafers to be processed are removed by wafer handler 405 from a selection of substandard or equivalent wafer cassettes 402-403 in wafer handler and load lock module 400. Wafer handler 405 transports a selected wafer from its cassette to wafer aligner and flat finder 408 and from wafer aligner 408 to load lock chamber 406 . Wafers may also be removed from cassette 404. Cassette 404 is reserved for processing qualification wafers. Cassette 401 is a storage cassette that allows wafers to be cooled after processing before being placed in one of the other cassettes or thin film monitor 409. The wafer cassettes 401-404 are tilted at a small angle 1, e.g.
The flat surfaces of the wafers in 1-404 are oriented vertically by this same small angle so that the weights, when placed in these cassettes, are tilted in a known orientation relative to the wafer holding slots in the cassettes. During the transfer of selected wafers from their cassettes to load-lock chamber 406, the wafers are first transferred to wafer handler 406.
5 to the wafer aligner 408, keeping the surface of the wafer in a vertical orientation. Next, rotate the selected wafer.

The flat surface of the wafer is level and the load lock 40
6. Load lock 406 is then opened to the atmosphere. Next, the flat surface of the gate valve module /l/10 is transferred by the transfer arm 201a.
0a remains horizontal while transporting the wafer through transfer module 200a'. Transfer arm 201a,
Transfer module 200a and gate pulp module 1
00a inlet/outlet port 210'! Stretch through z,
The wafer is pulled into the load lock chamber 406.

The transfer module 200a has four ports 210, 21
1.212 and 213. port 210.211
and 212 are gate pulp modules 100, respectively.
Controlled by a, 100b and 100C.

Port 211 and its corresponding gate pulp module 100b are connected to chamber 215 of transfer module 200a.
Chamber 301a of processing module 300a (!:
Connecting. Similarly, port 212 and corresponding gate valve module 100c H, transfer module 200a
The chamber 215 of the processing module 300b is connected to the chamber 301b of the processing module 300b. The internal chamber 215 of the transfer module 200a is maintained at a selected pressure less than atmospheric pressure by a conventional pumping mechanism (not shown in FIG. 1). To increase the rate at which chamber 215 is evacuated, chamber 215 is sized to minimize the volume of chamber 215 relative to arm 201a.

After removing the wafer from load lock chamber 406, transfer arm 201a retracts into transfer number 215 and gate pulp 100a closes. Next, transfer arm 2
01a is rotated by a selected angle to bring the wafer to the selected processing port 211 or 212 or transfer port 213. When the selected wafers are brought to the processing boat (e.g. port 21), the corresponding gate valve module (e.g. module 100)
b) Load lock 406 Kara transfer module 200
a is closed during transfer into the chamber 215, and the control device (
(not shown). Arm 201a then extends through a processing boat (eg, port zu) and a corresponding gate valve module (eg, module 100b) to a corresponding processing chamber (eg, chamber 301a of a corresponding processing module (eg, 300a)). The wafer is then extracted by means not shown in FIG.

The processing modules 301a and 301b are the same,
Therefore, the same operation may be performed there.

Alternatively, these modules may be different with different operations to be performed therein. In either case, ports 211 and 2, respectively, with input/output port 210 and valve 100a connecting to transfer module 2Of) a wafer handler and load lock 400.
12 and gate valve modules 100b and 100
By providing two processing modules 300a and 300b connected to the transfer module 200a via c, higher throughput and non-continuous processing of wafers is possible compared to continuous processing equipment. . The time required to transfer a wafer from a wafer cassette and extract the wafer in a selected processing module is typically shorter than the time required for processing a wafer in a processing module. . Therefore, the first wafer is transferred from the input cassette to processing modules 300a and 300b.
A second wafer is transferred from load lock chamber 406 to a selected one of processing modules 300b during an initial period of processing in processing chamber 300a.
may be transported to. next.

Transfer arm 201a may rotate back to port 211 to await completion of processing of the wafer in processing module 300a. Therefore, for a significant portion of the time, processing is occurring simultaneously in processing modules 300a and 300b. If desired, the processing module 300b can perform pre-treatments other than sputtering, such as for depositing metal thin films by chemical vapor deposition, or for performing sputter etch cleaning, when the main processing station is used for sputter deposition. It may also be a module.

The wafer can then be processed in the remaining processing chambers of the apparatus 1.

A second entrance/exit robot within the transfer module 200a)
213, other processing modules 30
Connection to 0c and 300d becomes possible. Transfer module 200a is connected via one-pass module 500 to an equal transfer module 200b (corresponding parts have the same reference numbers). Pass-through module 500 connects the inlet/outlet boat 213 of transfer module 200a with the inlet/outlet port 210 of transfer module 200b, thereby forming a single vacuum chamber. Arm 201
A wafer held by a processing chamber 300
c and 300d, it is extracted into a flat aligner 501 in a Ueno-B1 pass module 500. The wafer is then placed on the arm 201b of the transfer module 200b and transferred to the corresponding gate valve modules 100d to 100 by arm 201b from the processing modules 300c to 300e.
Transported via of. When the wafer is completely processed, the wafer is returned from the processing module to the selected cassette (401-404) via transfer arm 201a, or via transfer arm 201b, pass chamber 501 and transfer arm 201a. In the processing module, the wafer is in a dock-lock chamber 406. Processing module 300e is depicted with a dashed line.

Indicates that it is optional and that modules can be added freely.

The apparatus shown in FIG. 1 is linearly expanded by replacing gate valve 100f and processing module 300e by pass modules equal to one pass module 500, replacing transfer module 200b with transfer module 2.
It may also be connected to a transfer module (not shown) equal to 00b. Transfer module 200b is also connected to a plurality of corresponding processing chambers. The apparatus shown in FIG. 1 can also be extended in a non-linear manner by replacing the processing module 300d by a transit module equal to transit module 501 and connecting the transfer module 200b with a transfer module (not shown) equal to transfer module 200b. You may. The transfer module 200b is
connected to a plurality of corresponding processing chambers.

If desired, optional processing module 300e also.

The wafer handler and hero lock module 400 may be replaced by a second wafer handler and hero lock module.

The shape of the processing device shown in FIG. 1 allows for non-continuous processing. That is, the load lock 406 containing all wafers can be transferred to the selected processing chamber without passing through any other processing chambers, and all wafers can be transferred to the selected processing chamber without passing through any intermediate processing chambers. The selected processing chamber may be transferred to the color load lock chamber 406 or to all other selected processing chambers. The operation of the transfer arm, gate valve, flat aligner and load lock chamber within the device 1 is controlled by a main control circuit (not shown). The main control circuit typically operates such that the gate valves are continuous, so that non-specific processing chambers are in direct communication with other processing chambers. The device thus provides complete dynamic isolation.

The non-continuous processing provided by equipment R1 allows continuous operation of the remaining processing modules when a particular processing module is not operating.

Non-continuous processing also allows the performance of a replacement processing module, or of all specified processing modules, to be checked while the remainder of the system continues to operate. For example, if it is desired to check the performance of module 300c, a monitor wafer contained in cassette 404 is transferred to processing chamber 300c and
It may be processed and returned to cassette 404. During processing in chamber 300c, the remainder of the apparatus 1 continues to process wafer products.

FIG. 2 shows a partial perspective view of the semiconductor wafer transport and processing apparatus shown in FIG. In particular, transfer module 200a
The housing has a cylindrical shape with a circular upper part 298
, including a circular bottom portion 296 and a cylindrical wall 297 connecting the top portion 298 and the bottom portion 296 . The housing may be made of any suitable vacuum compatible material (eg, stainless steel).

Each transfer chamber boat is defined by an extension of the housing. The extension of the housing has an inner chamber 2
A horizontal slot is formed extending from 15 to the exterior of the housing. For example, port 210 (FIG. 1) is defined by housing extension 299a shown in FIG.

FIG. 3 shows a partial schematic plan view of a second embodiment of the wafer transport and processing apparatus of the present invention. The wafer transport and processing apparatus 2 includes an inlet wafer handler and load lock module 40a, an outlet wafer handler and load lock module 40b, transfer modules 20a and 20b, gate valve modules 10a-10h, M and processing chambers 3Qb, 30c, 53Of and 30g.
including. The wafer handler and load lock module 40a is the same as the wafer handler and load lock module 4oo shown in FIG. Transfer module 2
oal is a bow for communicating the inside 23a of the transfer module 20a with the outside of the module 20a) 21a -
21d. Boat 21a -
21d is opened and closed by gate pulp modules 10a-10d. Transfer module 20a is connected to an equal transfer module 20b via a flat aligner 50a, thus forming a single vacuum chamber. The chamber is evacuated by conventional pumping means not shown in FIG. flat aligner 50
a may be replaced by any suitable means for positioning the wafer in the desired rotational orientation. Transfer module 23b has four ports 21e-21h, which are connected to gate pulp modules 10e-10h.
respectively 'i1. Open and close. The interior 31c of the reactive ion etch module 30c is connected to the interior chamber 23a of the transfer module 20a and the interior chamber 23b of the transfer module 20b via bows 21c and 21h, respectively.

Ports 21c and 21h are gate pulp modules]
, Oc and 10h, respectively. Similarly, the internal chamber 31b of the sputter module 30b is
Internal chamber 23a of transfer modules 20a and 20b
and 23b through ports 21b and 21e, respectively, which connect gate pulp modules 10b and 1
0e respectively. Connect internal chamber 23b of H1 transfer module 20b with internal chamber 31g of chemical vapor deposition module 30g. Baud controlled by gate pulp module 10f) 21f
is transfer module~#20b tD internal chamber 23b
The internal chamber 31 of the high-speed annealing module 30f
Connect with f.

A main controller 60 communicates with each process chamber controller P, as well as with the inlet module 40a and outlet module 40b and the operator control panel via a standard communication bus 61.

In operation, a selected wafer is loaded by a wafer handler (not shown in FIG. 3) from a selected wafer cassette (not shown in FIG. 3) in inlet module 40a to flat finder 50b. It is transported to the lock chamber 46a.

Load lock chamber 46a is identical to load lock chamber 40b shown in FIG. Transfer module 20
The transfer arm 201c of a is connected to the load lock chamber 46a.
The port 21d is closed by the gate pulp module 10d. Next, one selected wafer is transferred to the transport arm 201c.
The transfer arm 201c then retracts into the internal chamber 23a of the transfer module 20a.

Arm 201c then rotates by one selected angle.

The selected wafer is brought to the wafer 21b or to the flat finder 50a. The wafer to be transferred to the flat finder 50a is transferred to the transfer arm 201.
d or transport arm 201c. Next, from the flat finder 50a, the transport arm 20
The wafers loaded on 1d are retracted into chamber 23b by transport arm 201d, rotated through the appropriate angle, and brought to the selected boat 21g or 21f. The gate pulp module controlling the selected boat then opens and the transport arm 201d extends into the internal chamber of the selected processing module where the wafers are extracted by means not shown in FIG. When a flat orientation is not required for a wafer or a circularly symmetrical substrate, the wafer or substrate is transferred from the transport arm 201c into the processing chamber 31c or processing chamber 3ib, respectively, via the gate pulp 10c and Job and further therein. via gate valves 10h and 10e, respectively, directly to transport arm 201d, bypassing flat finder 50a.

When the wafer is fully processed, it is loaded onto a transport ahem that assists the processing module. In the processing module, the wafer is installed.

Further, it is transferred back to the outlet port 21a. For wafers in processing modules 30b or 30c, this is accomplished through retraction of transport arm 201c from the processing chamber, followed by appropriate rotation of transport arm 201c. Next, the transport arm 201c is moved to the bottom 21a.
and extends into the load lock chamber 46b. Boat 21a is controlled by gate valve module 10a. For wafers in processing module 30g or 30f, the wafer is first transferred to transport arm 201d and then from arm 201d to arm 201c via flat finder 50a.

The apparatus shown in FIG. 3 has a third transfer module similar to transfer module 20b.
Indicates that it may be extended by tying it to a flat finder installed in the

The modules shown in the embodiment of FIG. 3 are interchangeable, allowing the device to be configured with any combination of modules that may be desired.

The apparatus shown in FIG. 3 has the same non-continuous processing advantages as the apparatus shown in FIG. The apparatus shown in FIG. 3 is somewhat more flexible in that transfer arm 201d serves four processing boats and transfer arm 201c serves two processing ports and both inlet and outlet modules. If desired, inlet module 41a may serve as both an inlet and an outlet module, and outlet module 41b may be replaced by a processing module. Similarly, any processing module may be replaced by an outlet module or by an inlet module, if desired.

4 and 5 show a partial schematic cross-sectional view and a partial cut-away cross-sectional view, respectively, of one embodiment of the gate pulp module 100. FIG. The gate pulp module 100 has a port PI
and port P. Port PI is defined by the first chamber housing extension 299x. The first chamber is either a processing chamber, a transfer chamber or a load lock chamber, and its extension defines a generally rectangular slot. The slot is sized to match the extension therethrough of the wafer transport arm 201 shown in FIG. Such an extension (2) of the housing of the transfer module 200a
99a) is shown in perspective view in FIG. Port P2 is similarly defined by an extension 299y of the second chamber (not shown in FIG. 4).

Housing extension 29 defining ports P+ and P2
9x and 299y are the first plurality of screws SI and the second plurality driven through 7 langes 295 and 296, respectively.
It is attached to the pulp body 102 by a plurality of screws S2. Pulp body 102 may be made of stainless steel or other suitable material. flanges 295 and 29
6 and the body 102, providing a vacuum seal. Pulp body 102 has horizontal slots 160. slots)
160 is connected from port P1 to port P when pulp gate 125 is lowered to the position shown by the dashed line in FIG.
Extends to 2. Slot 160 is shown in side view in FIG. 5 and is sized to match the extension of wafer transport arm 201 shown in FIG. 6 from port P+ to port P2. Dashed line A in FIG. 5A indicates the midplane of slot 160. When pulp gate 125 is in its fully retracted position, it does not extend into slot 160.

This position is indicated by the dashed line in FIG. gate 1
When 25 is in its fully extended position, elastomeric O-ring 104 is seated within notch 104a and forms a vacuum seal between ports PI and P2. Nystomer strips 106 and 107 placed within notches 106a and 107a, respectively, perform no vacuum sealing function. Conversely, when pulp gate 125 is in its fully extended position, strips 106 and 107 provide contact between body 102 and gate 125 and 1
A rotational moment is created at gate 125. The moment is caused by the contact between the elastomer O-ring 1041, the main body 102, and the valve gate 125.
The rotational moment for 25 is opposite. In cross section.

The pulp gate 125 has two trapezoids 125a and 125
It is a conjugate of b. Edge B+ of trapezoid 125a is 1 point 1
09 to point 108, forming an acute angle alpha of approximately 45 with the horizontal. Significantly large angles are undesirable since it is difficult for the elastomeric O-ring 104 to engage the body 102 in an airtight manner when the pulp gate 125 is fully extended. Edge E2 of trapezoid 125b forms an angle beta with the horizontal. In the embodiment shown in FIG. 4, angle alpha is equal to angle beta.

and i′L are not important.

A novel feature of the gated pulp module 100 is the asymmetry of the pulp gate cross section. Since only the O-ring 104 provides the vacuum sealing function, the trapezoid 125b is the same as the trapezoid 1.
It is made narrower than 25a. That is, line segment 126
The length of line segment 127 is shorter than that of line segment 127. In one example, the difference in length between line segment 126 and line segment 127 is approximately 1 inch (2.54 cm). For this reason, port P+
and port Pt is significantly reduced compared to prior art pulp modules. Prior art pulp modules use two O-rings and are trapezoidal 125b
is congruent with trapezoid 125a.

Bearings 110 and 111 serve to guide pulp gate 125 as it vertically translates within slot 144 of body 102.

The pulp gate 125 is attached to a shaft 132 which is threaded onto the pulp gate 125 by a threaded extension 133 of the shaft 132.

Pulp body 102 is attached to housing 138 by screws (not shown). metal bellows 130
is attached to the main body 102 by the flange 134 by screws 55. Stainless steel shaft 140 has a larger diameter than stainless steel shaft 132. An elanuttomer O-ring 134a between the flange 134 and the pulp gate body 102 is connected to the atmosphere outside the pulp module 100 and a chamber (not shown) connected to ports Pt and P2.

Provides airtightness. The shaft 132 is the shaft 140
It is coaxial with the shank and is rigidly attached to the shank) 140. Shaft 140 translates vertically within the cylindrical cavity 141 formed by housing 138 and thus causes pulp gate 125 to translate vertically within slot 144 . As shown in FIG. 5, shaft 132 is positioned such that longitudinal axis 128 of shaft 132 is located at the longitudinal midpoint of pulp gate 125 having length L. As shown in FIG. Shaft 132 is still available.

It is positioned so that the sum of the moments about the axis perpendicular to the cross section shown in FIG. 4, the lower surface of the pulp body, and the passing axis 128 is zero. These moments are
When the pulp body 102 is fully extended, the O-ring 104
and by the forces acting on the elastomer strips 106 and 107. Housing 138 is attached to air cylinder 150 by screws 56. Shaft 140 is vertically translated by a conventional air-driven piston mechanism 150.

FIG. 6 shows a plan view of the wafer transport arm mechanism 201, and FIG. 7 shows a partially cutaway side view. Arm mechanism 201 is one embodiment of transfer arm 201a used in transfer module 200a of FIG. 1 or arm 201 of module 20 of FIG. 3. The arm mechanism 201 includes a cam 24ζ, a first rigid arm 252, a pulley 254, a second
Includes rigid arm 256 and wafer holder 280.

The wafer holder 280 schematically illustrated in FIG.
It is fixedly attached to one end of 6. The other end of arm 256 is rotatably attached to one end of arm 252 by shaft 272 . Shaft 272 passes through one end (252b) of arm 252 and has one end secured to arm 256 and the other end secured to the center of Puyu-IJ 254. Shaft 272i, as shown in FIG.
It rotates with nomawashi. For this reason.

Arm 256 rotates together with pulley 254 .

Other end of arm 252 (252a) Fi shaft 232
The shaft 232 is the inner shaft of the dual shaft coaxial feedthrough 224 (FIG. 7). The vacuum feedthrough 224 may be one such as a ferrofluid feedthrough.
idicfeed through) to provide vacuum sealing between the interior of the housing 220 of the wafer arm mechanism 201 and the exterior of the housing 220. Vacuum feedthrough 224 is attached to housing 220 by flange 222. Such ferrofluidic feedthroughs are well known to those skilled in the art and, for example, the ferrofluidic feedthrough manufactured by Ferrofluidic, Inc. was described herein. It may be used to implement the drive mechanism. The outer shaft 238 of the ferrofluidic feedthrough 224 is secured to the cam 242. Both inner shaft 232 and outer shaft 238 are independently rotatable about a longitudinal axis 250 of shaft 232 and shaft 238 by a pair of motors 230 and 231 (not shown). The shaft 250 is the arm 2
01 and passes through the center of the vacuum chamber 215.

The belt 243 is attached to a part of the periphery of the cam 242 and
It is in contact with part of the surrounding area of J254. belt 243
is fixed to the cam 242 at a point 242f on the circumference of the cam 242, and fixed to the pulley 254 at a point 254f on the circumference of the pulley.
It is fixed at f. Belt 243 may be, for example, a stainless steel non-toothed belt or a metal cable.

FIG. 6 shows the transport arm mechanism 201 fully extended through the boat PL. In this example, when arm 201 extends fully through boat PL.

The angle θ between the axis M, that is, the midline of the arm 252 passing through the shafts 250 and 273, and the midline A of the boat P+ passing through the shaft 250 is approximately 30. In other embodiments, other corners may be selected at 30 positions. In operation, the arm 201 is attached to the shaft 25 while keeping the cam 242 fixed.
is retracted through P+ by rotating arm 252 counterclockwise around P+. This is done by rotating the inner shaft 232 of the ferrofluidic feedthrough while the outer shaft 238 remains stationary. Cam 242 is configured such that arm 252 rotates in a counterclockwise direction, and stainless steel cable 243 is wound and unwound around cam 242 to rotate Puyu-IJ 254.

To this end, wafer holder 280i moves in a generally straight path along midline A from its fully extended position to a retracted position within vacuum chamber 215, as indicated by dashed line position 280'.

When partially retracted into the wafer transfer arm 201 and the capacitor 215, both the arm 252 and the cam 242 are rotated by the same selected angle, respectively, into the internal shaft 23.
2 and the external shaft 238 by the selected angle so that the arm mechanism 201 is properly positioned to extend through the second selected boat. Boat PI-P4 shown in Figure 6
is 90 minutes away.

Therefore, in this embodiment, shafts 232 and 238
positions the wafer transport arm 201 so that it rotates by a multiple of 90 and extends past the other boats.

The extension is performed by rotating arm 252 about the axis of shaft 232 in a clockwise direction with respect to cam 242.

Importantly, as the stainless steel cable 243 wraps around and unwraps from the cam 242 as the wafer transport arm 201 is extended or retracted through the selected boat, there is no slippage between the cam 242 and the cable 243. Or, there is no rotational friction. This design is therefore particularly suitable for maintaining a clean environment within the vacuum chamber 215.

Cam 242 must be specifically shaped to ensure that wafer holder 280 retracts (and extends) along axis A in a generally linear manner. If the motion is linear, a single plane geometry defines the port axis A and the axis M
and the angle θ between the center of the wafer holder 280 and the sixth
The angle phi between the arm axis N and the axis M that connect the passing axis 273 in the plane of the figure is:

yields that it is related by the following equation.

Phi=90-θ+cos ((d/f)sin
θ] However, d is arm 2 from axis 250 to axis 273
52, and f is the length from the axis 273 to the wafer holder 2.
is the length of axis N to the center of 80.

The surface work is the difference (decrement) in the angle phi for a constant increment in the angle θ of θ, phi, 3. Delta phi, the ratio of the decrement in the phi divided by the corresponding increment in θ, the axis 2
73 x, y coordinates and stroke (d = 10 inches (25,4 cm) and f = 14 inches (35,56 cm)
), the X coordinate of the center of the wafer handler 280)
The printout is shown below.

Cam 2421″i, designed in two steps. First, the ratio between the decrement delta phi at angle phi divided by the corresponding incremental delta θ at angle θ is calculated for each θ. These ratios are used to design the theoretical cam profile. If r represents the radius of Puyu-IJ 254, then for each color θ (where 0 and θ<180), (Delta Phi/Delta A line segment with length θ)r is placed with one end at the origin, and the line segment is θ−90 from the origin.
Stretch out at the corner of. A smooth curve passing through the ends of these line segments (radii) defines a portion of the theoretical cam profile.

The remaining part of the theoretical cam outline (180<θ<360) is.

The cable 242 consists of a fixed length, and the cable 24
The cam profile is defined by the need to be symmetrical about the origin since it must wrap around on one side of the cam 242 as it unwinds from the other side.

The cam 242 then drives the pulley 254 by means of a smooth stainless steel belt that wraps around and unwraps around the pulley 242, so the transformation to the profile must be done to provide this physical drive. An iterative feedforward deformation process is used as described by the flowchart in FIG. 7A. With heuristics.

The program selects the angle θ. and the corresponding theoretical cam radius R6 starting with the first radius R0, the selected positive integer N, and the angle θ for the selected delta θ.

+delta θ, θo+2 delta θ.

11. , θo+N (delta θ) with subsequent theoretical radii R1, R, . . . , RN. "Interference" is defined by the imbalance that occurs in the flowchart. Each time an interference is found,
The theoretical radius is reduced by o, ooiz, so that the initial radius is
The process is repeated until it is shortened to avoid "interference." This reduced value R6 is then the actual cam's initial radius (for the angle θ.). The whole process is then repeated for the first order theoretical radius R+ and so on. The reduced radii Ro, R, . . . define the corresponding portions of the actual cam profile by passing smooth curves through the end points of these radii.

Constant 0.001 and 7th A by which the radius is shortened by that amount
0.002 in the unfairness of the test in the flow chart of the figure
and the maximum allowed error may be replaced by other small constants depending on the degree of accuracy desired. FIG. 7B shows that using the above process to define the effective portion of the cam profile 242 (where N=7 and delta θ=3), r=
1 shows the movement of a point at the center of the wafer holder along the path P for the case d=10, f=14 as well as the actual cam profile.

In that figure, the actual portion of the cam profile occurs for values of θ from 25 to 125. The effective portion of the cam profile is the portion of the profile that the stainless steel belt 243 wraps and unwraps. Although the effective cam is also defined by symmetry around the origin.

The winding and unwrapping in the left half plane is not shown for clarity. The ineffective portion of the cam may be defined in any manner that does not interfere with the effective contour of the cam 342, for example, as illustrated in FIG. 7B, which is drawn to scale. The fixed point 242f may be selected as any point on the inactive portion of the cam profile that the belt contacts. Fixed point 254f is selected such that induced rotation of pulley 254 does not cause fixed point 254f on belt 243 to rotate away from pulley 254. If you wish.

The belt is connected to the first
From the fixed point of the cam 242 by turning the pulley 254,
may be extended back to a second fixed point in an inactive region of the contour.

In the embodiment described above, pulley 254 is circular.

However, a similar process for defining the contour of cam 242 to provide linear motion may be used with circular pulley 254 to be replaced by a non-circular cam (pullery).

In another embodiment of a particularly preferred wafer handler and load lock module 400 (FIG. 1), three or more cassettes of wafers are vacuumed in separate load locks to facilitate high speed processing and outgassing of the wafers. supplied within. As shown in FIG.
and 406 are respectively load lock chambers 408.
Illustrated within 410 and 412. The cassette is at door 4
14. Supplied from the clean room through 416 and 418. These load lock chambers are evacuated from below by suitable pumping means (not shown). When the appropriate level of vacuum is achieved, the pulp 420, 42
2 or 424 (shown only schematically) may be opened to allow movement of the wafer from the cassette into the wafer load lock handling chamber. Within chamber 426, handling arm drive mechanism 428 is mounted on track 430. The handling arm drive mechanism 428
30 to the load lock chamber 408
．． 410.412. A two-piece arm 432 is mounted above and driven by handling arm drive mechanism 428 . arm 432
is pulp 420.422.

422 and is used to lift the cassette, remove the cassette, or return the cassette. An elevator (not shown) below the table on which the cassette is placed raises the cassette;
Alternatively, it can be lowered to allow the arm to reach different wafers within each cassette. Arm 432 can be used to move the wafer to a placement table 434 from which it is lifted by other wafer handling equipment of the apparatus.

The hot wafer lifted by arm 432 is
The wafer is moved to be placed in a cassette 436 or 438 to allow the wafer to cool before being transferred back to the cassette.

An important feature of the present invention is that the handling arm 1 drive mechanism 428
A concentric wafer orientation device incorporated within the wafer orientation system. A table 436 is positioned on the shaft (not shown). The shaft is concentric with a shaft that connects handling arm drive mechanism 428 to handling arm 432. This array is
Illustrated in FIG. A wafer is placed on table 436 by arm 432. Tail 436 rotates so that the edge of the wafer passes between light emitter 438 and light detector 440. Rotation of the edge of the wafer through the light beam yields light intensity variation information as a function of rotation angle that allows the central computer to calculate the location of the centroid and plateau of the wafer. The computer then stores information about the true center of the pool to align with the flat and place the wafer on the table 434. Further details of this embodiment of the load lock module are described in a co-dated U.S. patent application to Richard G. Burchill et al. entitled "Wafer Transport Apparatus."

The disclosure of which is incorporated herein by reference.

Also a wafer pass module 500. The same rotational plateau alignment described above can be used in plateau aligner 501. A rotatable table 436 is connected to the module 500.
The wafer is housed inside. A light emitter 438 and a light detector 440 are used to provide light intensity information to enable alignment of the light as described above.

FIG. 10 shows a schematic diagram of one embodiment of a sputter module 350. The sputter module 350 has a pre-treatment true '2
fenha301. The wafer handler arm 340 , the pulp 338 that provides a vacuum seal between the processing chamber 301 and the toss chamber 302 , the sputter source 304 , the heater 315 . and a matchbox 316. In operation, the wafer is placed in the gate pulp module 1100t.
Inside the transfer chamber 200 (7) Woo! -/・Transport arm mechanism (not shown in Figure 10, but shown in Figures 6 and 7)
(as shown in the figure) to Ueno No.
will be transferred to. The arm 340 is illustrated in more detail in FIGS. 11-14 and 16. The gate pulp module 1100t is the same as the gate pulp module xoo shown in FIGS. 4 and 5. When the wafer transfer from the transport arm mechanism in chamber 200 to wafer handler arm 340 is complete, pulp 1100t is closed via a control mechanism (not shown). In this manner, the atmosphere within processing chamber 302 is isolated from the atmosphere within transfer chamber 200. Next, wafer handler arm 3
40 rotates the horizontal wafer W held therein by 95 in the processing chamber 301 so that the plane of the wafer W makes an angle of 5 with the vertical. This rotation is shown in perspective view in FIG. Next, Ueno No Dora Arm 340
is the pulp opening 3 with the wafer W held therein.
38 into the processing chamber 302 and then rotates by 5 with the wafer W, so that the plane of the wafer is vertical and a part of the back side of the wafer W is exposed to the heater 3.
15. Heater 315 is well known to those skilled in the art and may be, for example, US Pat. No. 6,825,30 manufactured by Parian Associates, Inc. Matchbox 316 provides impedance transfer between the RF heating source (not shown) and the heater glow discharge. Bring the wafer to the selected temperature 2
Sputter source 314 is then activated via a control mechanism (not shown in FIG. 10). Gas line 309 brings argon gas to pulp 310 at a selected pressure. Needle pulp 311 controls the flow of argon from pulp 310 to sputter chamber 302. The needle pulp 312 controls the flow of argon into the cavity formed between the backside of the wafer W and the heater 315; Switch 308 is a pressure start switch and is a pressure start switch for chamber 302.
act as a backup safety switch to cut power to the sputter source 304 and all other electrical equipment coupled to the sputter module when the pressure within the sputter module rises above a selected level below or equal to atmospheric pressure. . The interlock switch 306 is connected to the access door (
(not shown) is a safety switch that cuts power to source 304 when open.

Similarly, interlock switch 314ii' is a safety switch that cuts power to heater 315 when the cooling water flow fails. Gauges 318 and 319 are connected to chamber 30
Measure the pressure inside 1. roughing gauge
ing gauge) 318 measures pressure in a range between atmospheric pressure and 10 Torr. ion gauge 319
measures pressures below 10 Torr.

Interlock switch 317 is a safety switch that cuts power to prevent pulp 338 from opening when chamber 301 is at atmospheric pressure.

A silent manometer gauge 320 is a pressure measuring device that senses the pressure within the chamber 301 and may be isolated from the chamber 301 by the pulp 313 .

The pumping mechanism used to evacuate chamber 301 is well known and includes a roughing pump 323.

Pump 323 reduces the pressure in chambers 301 and 302 to a selected pressure, approximately 10 Torr, via valve 336. A high vacuum pump 322, such as a cryopump, then further evacuates chambers 301 and 302 via valve 324 when valve 336 is closed. The valve 324 is connected to the chamber 30
1 is closed to protect pump 322 when vented to atmosphere. Chambers 301 and 302 are filled with traps (tr) with a pump system foreline.
ap) (not shown). valve 325
is used to evacuate pump 322 to open the pump.

FIG. 16 shows a cross-sectional view of a mechanism for transferring a wafer from the wafer/transport arm mechanism 201 shown in FIGS. 6 and 7 to the wafer arm 340 in the sputter module pretreatment chamber 301. Ueno Ga.

The wafer W is transported into the chamber 301 by the arm mechanism 201 (not shown in FIG. 16 but shown in FIG. is located above the first table 500. table 50
0 is fixedly attached to shaft 501 , which is movable in vertical linear translation as indicated by double-ended arrow 518 driven by air cylinder 502 . Shaft 501 passes through flange 397 and into vacuum chamber 301 . Bellows 522 is welded to flange 398 and attached to flange 398 and seven flange 397 of housing 396. Elastomeric O-ring 520 and bellows 522 between bellows 522 and shaft 520 provide a vacuum seal between chamber 301 and the outside atmosphere. The table 500 is
It is dimensioned to rise through a circular opening in wafer holder 280 (see FIG. 6) to remove the wafer from wafer holder 280. Wafer holder 2
80 is first retracted from chamber 301 as described in connection with FIGS. 6 and 7.

At this point, wafer W is placed on table 500 as shown in FIG. The edge of Ueno W extends beyond the perimeter of table 500 in the corrugated region of table 500 (not shown). The corrugated region will eventually engage the edge of the wafer. Wafer arm mechanism 340
(as explained below), a circular opening 342 (FIG. 11) in wafer holder plate 341 is centered above wafer W. circular ceramic ring 5
11 is attached to the lower rim 510 of wafer plate 1-341. A plurality of flexible wafer clips are secured to the ceramic ring 511 at approximately equal intervals.

The two clips 512a and 512b are shown in FIG. Prongs corresponding to each flexible waeno clip are rigidly attached to second table 514. Prongs 514a and 514b corresponding to clips 512a and 512b are shown in FIG. Table 514 is rigidly attached to shaft 503 which is vertically linearly translatable as shown by double-ended arrow 516 driven by air cylinder 504 . The shaft 503 is also. It passes through the housing 396 of the chamber 301. The bellows 523 is attached to the 7 flange 398 of the housing 396 and the elastomer O-ring 521 is between the bellows 523 and the shaft 503.

A vacuum seal is provided between chamber 301 and the outside atmosphere. When the wafer W is transferred to the table 500, the table 514 is then raised and each prong attached to the table 514 engages its corresponding flexible wafer clip, thereby opening the clip. Next, the table 500 is raised and the wafer W is aligned with the open clip. Table 514 is then lowered to close the clips and engage the edges of wafer W. FIG. 16 shows clips 512a and 512b engaging the edges of wafer W at the dashed position layer. table 5
00 is then lowered again. This completes the transfer of wafer W from arm 201 to arm 340.

Arm extensions 345 and 34 of the wafer plate 34
6 (FIG. 11) is rigidly attached to the shaft 365.・/Gift 365 has arm extension 345 and 3
It grows between 46 and 46. This is illustrated on a larger scale in FIG. Shaft 365 passes through gearbox 360. Gearbox 360 includes a conventional right-angle gear mechanism 361 that couples rotation of drive shaft 367 to shaft 365 . Drive shaft 367 is rotated by rotating a pulley 368 rigidly attached thereto and driven by a suitable mechanism (eg, a belt attached to first motor M+ within housing 370). The motor Ml drives the wafer arm 340 about the shaft 365 horizontally (the 12th
(shown in the figure) along with the wafer W for 95 rotations.

The wafer W is attached to the rim 5 of the wafer arm plate 341.
It is fastened to a ceramic ring 511 attached to 10.

Shaft 367 has a dual shaft coaxial feedthrough 388 (may have ferrofluid air tightness)
It is an internal shaft. Shaft 367 passes from vacuum chamber 311 through nozzle 396 to external pulley 368 . Elastomeric O-ring 373 provides a vacuum seal between vacuum chamber 301 and the external atmosphere of chamber 311. The outer shaft 378 of the ferrofluid quick feedthrough 388 is connected to the inner shaft 3
67 and further extends through housing 396 to pulley 369 . The pulley 369 is rigidly attached thereto. external shaft 378
is rotated by rotating the pulley 369 by suitable means, for example a belt, attached to a motor M in the housing 370. The elastomeric O-ring 3 between the ferrofluidic housing 374 and the external shaft 378 provides a vacuum seal between the chamber 301 and the atmosphere outside the chamber 301. Housing 374 is welded to flange 375.

Flange 396a is fixed to seven flange 375 with bolts. Flange 396a is welded to chamber wall 396. O-ring 371 provides a vacuum seal between chamber 301 (via flange 396a) and feedthrough 388.

When the wafer arm 340 is rotated approximately 95 degrees from horizontal as shown in FIG.
38 and into sputter chamber 302 .

This rotation is accomplished by rotating external shaft 378 by motor M. The end of shaft 378 inside chamber 301 is rigidly attached to gearbox housing 360. shaft 378
When the gearbox 360 rotates in a counterclockwise direction, the gearbox 360
．． The shaft 365 and the wafer arm 340 are
All rotate in the counterclockwise direction shown in the figure. Rotation of the corner of the dowel 90 positions the ueno W in front of the heater 315. By rotating the inner shaft 367 again.

Ueno W attached to ceramic ring 511
is attached to Ueno arm plate 341,
Only the corner of the dowel 5 rotates, so that its back side is heated by the heater 31.
Contact with 5. Ueno arm 340 is heater 315
When properly positioned with respect to
44a.

The wafer holder plate 341 may consist of one movable plate/shield or two stainless steel layers 341a and 341b, as shown in cross-section in FIG.

Upper layer 341aFi is movably attached to lower layer 341b by two screws (not shown). upper layer 34
1a shields the underlying layer 341b from sputter deposition and helps form reduced sputter deposition on the edge shield 530 surrounding the ceramic ring 511. layer 341
a is replaced each time sputter deposition over layer 341a builds up to an undesirable level. Sputter source 3
04 is well known in the industry, for example, t is the sputtering source 304.
may also be BA1F Ancon Mag (US registered trademark), and therefore will not be described here. The sputter source 304 is
Hinge 304a (FIG. 11) pivots open to allow access to the source target and shield.

Wafer handler arm 340 pre-processing chamber 301
When inside, the pretreatment chamber 301 is rectangular)' 7
351 K, so it may be vacuum isolated from Subatutacheno <302. Rectangular door 351, brace (br
ace) 353 to the shaft 391. The shaft 391 is rotated by the starter 380 through the crank arm, so that the door 351 is slightly offset at the front from the rectangular opening 338 into the vine chamber 302. As shown in FIG.
1C, the dimensions are larger than the opening 338. Door 351 is Shan) 391,! : Slidable;
The O-ring 352 is translated linearly so that the O-ring 352 sealingly engages the Cheno crank surrounding the aperture 338. To this end, shaft 355 is translated along axis C so that end 355a engages door 351 and translates door 351 along axis C towards opening 338. The mechanism for the drive shaft 355 contained within the no-uji puffer 381 is illustrated in more detail in FIG. Shaft 355 is translated in either direction along axis C by a conventional air-driven piston attached to shaft 355. When the shaft 355 extends only partially toward the opening 338, the O-ring 3
83 provides a dynamic vacuum seal between chamber 301 and the atmosphere. However, when the shaft 355 is fully extended and the door 351 is rotated away from its airtight position and into its rest position as shown in FIG. engagement, such that a static vacuum seal is formed between the housing 381 and the annular extension 355b. This new static seal provides more reliable vacuum isolation between the chamber 30 and the atmosphere.

Although the Modiny Lauer transfer and processing apparatus of the present invention is described primarily for application in the processing of semiconductor wafers or substrates, it is understood that the inventive apparatus may be utilized in the processing of many other wafers or circular workpieces as well. You'll understand.

Such other workpieces need not have flats at their edges, and workpieces that are sufficiently circular in outline can be treated similarly.

More particularly one inventive device is particularly useful for processing any magnetic or optical storage medium in wafer-like or circular form.

The invention is not limited to the preferred embodiments and their variants, but the features of the invention summarized in the claims,
In fact, modifications and improvements may be made, including mechanically and electrically equivalent changes to the components, without departing from the scope of protection.

[Brief explanation of drawings]

FIG. 1 is a partial schematic plan view of an embodiment of a device according to the invention. FIG. 2 shows a partial perspective view of the device shown in FIG. FIG. 3 shows a partial schematic plan view of a second embodiment of the device according to the invention. FIG. 4 shows a partially cutaway side view of a gate valve module according to the present invention. FIG. 5 shows a partially cutaway plan view of the gated pulp module of FIG. 4. FIG. 6 shows a schematic plan view of a knee/transport arm according to the invention, with the arm shown in broken lines in the second position; FIG. 7 shows a partial cross-sectional view of the arm of FIG. 6. FIG. 7A shows a flowchart for obtaining an actual cam outline from a theoretical cam outline. FIG. 7B shows one embodiment of the actual cam with the path traced by the center of the way/holder. FIG. 8 shows a schematic plan view of a particular preferred embodiment of a load lock module according to the present invention. 9 shows a perspective view of the waeno handling arm and aligner of FIG. 8; FIG. FIG. 10 shows a schematic diagram of an embodiment of a sputter module according to the invention. FIG. 11 is a partially sectional plan view of a sputter module according to the present invention. 12 is a partial cross-sectional perspective view of the module of FIG. 11; FIG. Figure 13 shows the first line along line 13-13 shown in Figure 15.
FIG. 13 is a cross-sectional view of the drive mechanism of the module of FIGS. 1 and 12; FIG. 14 is a cross-sectional view of the driver groove of the module of FIG. 11 taken along line 14--14. FIG. 15 is a cross-sectional view through the module of FIG. 11 along line 15--15. FIG. 16 is a cross-sectional view of the mechanism for receiving and removing the wafer from the transport arm along line 16--16 shown in FIG. 12. [Main symbols] 201...Wafer transport arm mechanism 215...Vacuum chamber 232...Inner shaft 238...Outer shaft 242...Cam 243...Stainless steel cable (belt) 250...
...Axis 252...First rigid arm 254...Puyuri 256...Second rigid arm 272...Shaft 273...Axis 275...Bearing 280...Ueno holder patent applicant Parian・Associates Incorporated

Claims (1)

[Scope of Claims] 1. A semiconductor substrate transport arm comprising: a first cam; a second cam; a first fixed point on the periphery of the first cam and a part of the periphery of the second cam; The second cam around the first cam
a smooth belt extending back to a fixed point and having a third fixed point on the second cam; a first arm member having a first end and a second end; a first arm member rotatably mounted on the first cam at the first end; a second arm member having a first end and a second end, the second end holding a semiconductor substrate; a second arm member configured to rigidly connect the first end of the second arm member and the second cam, the shaft passing through the second end of the first arm member; a shaft; and means for rotating the first arm member relative to the first cam, the first cam being fixed;
rotation of the first arm member in a direction causes the belt to wrap around and unwind from the first cam, thereby rotating the second cam and the second arm rigidly attached thereto; The second end of the second arm member thus moves toward the first cam along a substantially straight path over a substantial portion thereof, and the second end of the second arm member moves toward the first cam in a second direction relative to the first cam. Rotation of the first arm member causes the belt to wrap around and unwind from the first cam, thereby rotating the second cam and the second arm member rigidly attached thereto, so that the means for moving said second end of said second arm member away from said first cam along a substantially straight path over a substantial portion thereof. 2. The semiconductor substrate transport arm according to claim 1, wherein the means for rotating the second end of the second arm member along a path having a length of at least D/2. (where D is the first
the distance between the axis of rotation of the first arm member and the axis of rotation of the shaft with respect to the cam). 3. The semiconductor substrate transport arm according to claim 2, wherein the substantial portion is at least D/2.
A semiconductor substrate transport arm. 4. The semiconductor substrate transport arm according to claim 1, wherein the second cam is circular, and the first cam is circular.
a cam in the first direction relative to the second cam;
A semiconductor substrate transport arm, wherein said rotation of said arm moves said second end of said second arm toward said first cam along said path that is substantially straight over a substantial initial portion thereof. 5. The semiconductor transport arm according to claim 1, further comprising the same selected angle about an axis passing through the first cam and the first end of the first arm. A semiconductor transport arm including means for rotating both the first cam and the first arm member. 6. The semiconductor substrate transport arm according to claim 5, wherein the means for rotating the selected angle is 90°, 180°, 270° and 360°.
, -90°, -180°, -270°, and -360°
a semiconductor substrate transport arm including means for rotating the semiconductor substrate; 7. The semiconductor substrate transport arm according to claim 1, wherein the substantial portion is at least 1/1/2 of the maximum path length traversable by the second end of the second arm member. A semiconductor substrate transport arm having a length of 2. 8. A semiconductor substrate transport arm according to claim 1, wherein the first fixing point coincides with the second fixing point. 9. A wafer transport device for moving a wafer over a predetermined path, comprising: an elongated first arm means having a wafer holding end; a first end thereof rotatably joined to the other end of said first arm means; a second elongate arm means, the second end of said second arm means being rotatably secured to the support means; variable ratio control means for said first and second arm means; extending the wafer holding end between a first position adjacent the support member and a second position moved from the support member over a first predetermined path without sliding or rotational friction; a control means, wherein the distance between one position and said second position is at least several times the diameter of said wafer. 10. The transport device according to claim 9, wherein the control means moves the wafer holding end over at least one other predetermined route, and the other route is the first route. transportation device in the same plane as the