WO2023283587A1

WO2023283587A1 - Compliant guiding mechanism for mechanical actuator

Info

Publication number: WO2023283587A1
Application number: PCT/US2022/073480
Authority: WO
Inventors: James E. Tappan
Original assignee: Lam Research Corporation
Priority date: 2021-07-09
Filing date: 2022-07-06
Publication date: 2023-01-12

Abstract

A mechanical actuator with a guide mechanism for guiding a translating body, e.g., a shaft, is disclosed. The guide mechanism may include three or more contact mechanisms attached to the translating body and a housing with an inner surface. The contact mechanisms may have contact bodies with outermost surfaces that are in contact with the inner surface of the housing and guide the translating body as it translates along a translation axis. The contact mechanisms may include non-compliant contact mechanisms and compliant contact mechanisms. The non-compliant contact mechanisms may fix the position of an outermost surface of the corresponding contact body radially relative to the translating body. The compliant contact mechanisms may have a compliant element that allows the position of an outermost surface of the contact body thereof to be movable between multiple radial positions relative to the translating body.

Description

COMPLIANT GUIDING MECHANISM FOR MECHANICAL

ACTUATOR

RELATED APPLICATION(S)

[0001] A PCT Request Form is filed concurrently with this specification as part of the present application. Each application that the present application claims benefit of or priority to as identified in the concurrently filed PCT Request Form is incorporated by reference herein in its entirety and for all purposes.

BACKGROUND

[0002] In semiconductor wafer processing, mechanical actuators are used to move different mechanical components to different elevations within a chamber, such as moving lift pins. In some cases, the lift pin may be used to lift an edge ring. In other embodiments, the lift pin may be used to lift a semiconductor processing wafer. In either case, it may be preferred that the mechanical component, e.g., an edge ring or a semiconductor processing wafer, be moved to a precise location.

SUMMARY

[0003] Details of one or more implementations of the subject matter described in this specification are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages will become apparent from the description, the drawings, and the claims.

[0004] In some implementations, an apparatus may be provided that includes a housing, a shaft, a drive system, and three or more roller mechanisms. The shaft may be located at least partially within the housing. The drive system may be configured to cause the shaft to translate relative to the housing and along a translation axis substantially parallel to a center axis of the shaft responsive to receipt of one or more control signals. Each of the roller mechanisms may be connected to, and may translate with, the shaft and may have a roller with an outer surface that is in contact with an inner surface of the housing. At least one of the three or more roller mechanisms is a compliant roller mechanism, each compliant roller mechanism including at least one compliant element configured such that at least a portion of the outer surface of the roller of that compliant roller mechanism may be movable between multiple radial positions relative to the shaft and with respect to the center axis and at least two of the three or more roller mechanisms are non-compliant roller mechanisms that do not include the compliant element of the compliant roller mechanism.

[0005] In some implementations of the apparatus, the at least one compliant element of each compliant roller mechanism may be configured to press the roller of that compliant roller mechanism against the inner surface of the housing with a force between one pound and three pounds.

[0006] In some implementations of the apparatus, the compliant element may be a spring. [0007] In some implementations of the apparatus, the compliant element may be a cantilever beam.

[0008] In some implementations of the apparatus, the compliant element may be an elastomeric material that provides the outer surface of the roller in the compliant roller mechanism.

[0009] In some implementations of the apparatus, at least one of the at least one compliant roller mechanisms includes a plunger. The plunger may be configured to translate along a radial axis relative to the shaft, may be urged radially outward by the spring, and the plunger may support the roller of that compliant roller mechanism relative to the shaft.

[0010] In some implementations of the apparatus, each of the rollers may be configured to rotate about a corresponding roller axis. The corresponding roller axis may be parallel to a corresponding reference axis perpendicular to the center axis of the shaft.

[0011] In some implementations of the apparatus, each roller mechanism may have a corresponding dowel pin configured to rotatably support the roller of that roller mechanism. [0012] In some implementations of the apparatus, each roller may be made of plastic.

[0013] In some implementations of the apparatus, the plastic may be a bearing grade polyamide-imide or a bearing grade polyether ether ketone (peek).

[0014] In some implementations of the apparatus, the housing may be made of aluminum- containing material.

[0015] In some implementations of the apparatus, the housing may have an inner diameter of 25 mm or less.

[0016] In some implementations of the apparatus, the housing may have a circumferential radial thickness in directions perpendicular to the shaft center axis less than or equal to 2.5 mm in at least a portion of a translation region of the housing that is between a first plane and a second plane. The first plane may be a plane defined by a first group of contact points between each of the rollers and the inner surface of the housing when the shaft is at a first limit of its translation and the second plane may be a plane defined by a second group of contact points between each of the rollers and the inner surface of the housing when the shaft is at a second limit of its translation.

[0017] In some implementations of the apparatus, an inner diameter of the housing may have a tolerance of ±0.03 mm.

[0018] In some implementations of the apparatus, the rollers of the roller mechanisms may be arranged in a nominally circular array about a shaft center axis.

[0019] In some implementations of the apparatus, there may be no more than three roller mechanisms.

[0020] In some implementations of the apparatus, there may be exactly four roller mechanisms, two roller mechanisms adjacent to one another may be non-compliant roller mechanisms and the other two roller mechanisms may be compliant roller mechanisms.

[0021] In some implementations of the apparatus, the shaft may be configured to translate relative to the housing by at least 25 mm along the translation axis.

[0022] In some implementations of the apparatus, the shaft may be configured to translate relative to the housing by at least 13 mm along the translation axis.

[0023] In some implementations of the apparatus, the drive system may include a motor connected to a lead screw interfaced with a lead screw nut, and the shaft may be rotatably coupled to the lead screw nut.

[0024] In some implementations of the apparatus, the apparatus may include a bellows and an end cap, the end cap may be fixed relative to the housing and connected with a first end of the bellows and the shaft may attach to a second end of the bellows.

[0025] In some implementations of the apparatus, the apparatus may include a lift pin that is attached to the shaft and has a lift pin center axis that is aligned with the center axis of the shaft. [0026] In some implementations of the apparatus, the pin may be made of aluminum oxide. [0027] In some implementations of the apparatus, the apparatus may include a semiconductor processing chamber, a pedestal, and an edge ring. The housing may be mounted so as to be fixed with respect to the semiconductor processing chamber. The pin may be extendable so that when the pin is extended, the edge ring is lifted.

[0028] In some implementations of the apparatus, the apparatus includes a radial gap in between the shaft and the inner surface of the housing. The radial gap may have a gap distance in directions perpendicular to the shaft center axis between an outer surface of the shaft and the inner surface of the housing in at least a portion of a translation region of the housing, the translation region of the housing may be between a first plane and a second plane, the first plane may be a plane defined by a first group of contact points between each of the rollers and the inner surface of the housing when the shaft is at a first limit of its translation, and the second plane may be a plane defined by a second group of contact points between each of the rollers and the inner surface of the housing when the shaft is at a second limit of its translation.

[0029] In some implementations, the apparatus may include a housing, a shaft, a drive system, and three or more contact mechanisms. The shaft may be located at least partially within the housing, the drive system may be configured to cause the shaft to translate relative to the housing and along a translation axis substantially parallel to a center axis of the shaft responsive to receipt of one or more control signals, and each of the contact mechanisms may be connected to and may translate with the shaft and may have a contact body with an outer surface that is in contact with an inner surface of the housing. At least one of the three or more contact mechanisms may be a compliant contact mechanism, each compliant contact mechanism may include at least one compliant element configured such that at least a portion of the outer surface of the contact of that compliant contact mechanism may be movable between multiple positions along an axis perpendicular to the translation axis and relative to the shaft, and at least two of the three or more contact mechanisms may be non-compliant roller mechanisms that do not include the compliant element of the compliant contact mechanism.

BRIEF DESCRIPTION OF THE DRAWINGS [0030] FIG. 1 shows an example of a mechanical actuator with a guide mechanism and rollers as contact bodies.

[0031] FIG. 2 shows a top cutaway of an example of a mechanical actuator with a guide mechanism.

[0032] FIG. 3 shows another example of a mechanical actuator with a guide mechanism with pads as contact bodies.

[0033] FIG. 4 shows an example compliant mechanism with a pad as its contact body and a non-compliant mechanism with a pad as its contact body.

[0034] FIGS. 5-1 through 5-4 depict various examples of compliant elements of a compliant contact mechanism.

[0035] FIG. 6 depicts a side view of part of an example semiconductor processing chamber having a mechanical actuator that is an example of the mechanical actuators discussed.

DETAILED DESCRIPTION

[0036] In the following description, numerous specific details are set forth to provide a thorough understanding of the presented embodiments. Embodiments disclosed herein may be practiced without some or all of these specific details. In other instances, well-known process operations have not been described in detail to not unnecessarily obscure the disclosed embodiments. Further, while the disclosed embodiments will be described in conjunction with specific embodiments, it will be understood that the specific embodiments are not intended to limit the disclosed embodiments.

[0037] Mechanical actuators may be used in some semiconductor wafer processing tools to move mechanical components, such as an edge ring, within a semiconductor processing chamber. In many implementations, it may be desirable that the motion of the actuators be precise to ensure the mechanical components are able to be repeatably removed from a particular position, e.g., a position that has been aligned to another component such as a pedestal used to support a wafer, and then replaced in that same position. Precise motion of the actuator allows mechanical components within the semiconductor processing chamber to be placed with precision where location is critical. In some embodiments, in a lift/place operation of the wafer-ring, the wafer-ring centeredness may be critical to wafer processing. A guide mechanism may be used to facilitate this operation and other similar operations. [0038] FIG. 1 shows a mechanical actuator 100 with a guide mechanism 102. The mechanical actuator 100 has a housing 106 with an inner surface 107 and a shaft 104 with a center axis 128. The shaft 104 is partially inside the housing 106. The guide mechanism 102 may be used to precisely guide the motion of the shaft 104 as the shaft translates along a translation axis 126 and moves relative to the housing 106. In the example shown in FIG. 1, the guide mechanism 102 is used to ensure that a pin 114 attached to the top of the translating shaft 104 is able to be driven to a precise location in a semiconductor processing chamber 176 by guiding the pin to a precise position on a plane (not shown) perpendicular to the translation axis 126.

[0039] The mechanical actuator 100 shown features an end cap 110. The end cap 110 is fixed relative to the housing 106. Interior to the housing 106 and having a portion thereof fixed to the end cap 110 are bellows 112. In some embodiments, the bellows 112 are metal bellows. The top end of the bellows 112 may attach to the end cap 110 and the bottom end of the bellows may attach to the shaft 104. The bellows 112 may be used to provide a flexible, yet hermetically sealed, interface between the shaft 104 and the end cap 110 that allows a vacuum to be maintained on a side of the end cap 110 having the pin 114 protruding therefrom, e.g., within the semiconductor processing chamber 176 when the mechanical actuator 100 is installed on the semiconductor processing chamber. In some embodiments, the pin 114 may be made of aluminum-oxide, an aluminum oxide-containing material, a ceramic, a metal, or other suitable material. On top of the end cap 110 is an O-ring groove 116 where an O-ring 117 may be placed when the mechanical actuator is attached to the semiconductor processing chamber 176. The O-ring 117 ensures a seal between the semiconductor processing chamber 176 and the mechanical actuator 100 when the mechanical actuator 100 is attached to the semiconductor processing chamber. When the mechanical actuator 100 is attached to a semiconductor processing chamber 176, the O-ring 117 and the bellows 112 may act to provide a gas-tight seal that allows a vacuum to be maintained within the semiconductor processing chamber while the area outside of the O-ring 117 and outside of the bellows 112 may remain at atmospheric pressure.

[0040] The mechanical actuator 100 may also include a drive system 108. The drive system 108 may be caused to translate the shaft 104 to along the translation axis 126. The drive system 108 may cause the shaft to translate responsive to a control signal, e.g., a signal from a controller (not shown) or computer. In some embodiments, the shaft 104 may be translatable by up to 25 mm. In some other embodiments, the shaft 104 may be translatable by at least 13 mm. In still some other embodiments, the shaft 104 may be translatable to over 25 mm. The translation axis 126 is substantially parallel to the center axis 128 of the shaft 104. In this embodiment, the drive system 108 features a motor 120. The motor 120 is connected to a lead screw 122 coupled with a nut 124. The motor 120 drives the lead screw 122 and as the lead screw 122 rotates, the nut 124, attached to the shaft 104, translates along with the lead screw. The shaft 104 translates with the nut 124 along the translation axis 126. As the shaft 104 translates, the bottom end of the bellows 112 translates with it while the top end of the bellows remains stationary. Thus, as the shaft 104 translates, the bellows 112 contracts and expands. [0041] The mechanical actuator 100 uses the guide mechanism 102 to ensure precise movement of the shaft 104. The guide mechanism 102 uses the inner surface 107 of the housing 106, the shaft 104 and contact mechanisms 130 to guide the translation of the shaft. The contact mechanisms 130 are each connected with the shaft 104 and have a contact body 132, e.g., a roller 140 in this example, which is in contact with the inner surface 107 of the housing 106. In some embodiments, the contact body 132 may be a pad. The mechanical actuator may include two types of contact mechanisms 130, a compliant contact mechanism 134 and a non- compliant contact mechanism (not shown but see FIG. 2). The compliant contact mechanism 134 has a compliant element 146 that allows an outermost surface 133 of the contact body 132 to be movable between multiple radial positions relative to the shaft and with respect to the center axis. The non-compliant contact mechanism has a contact body 132 without a compliant element. The outermost surface 133 of the contact body 132 is thus fixed in its radial position relative to the shaft. The contact mechanism 130 shown in FIG. 1 is a compliant contact mechanism 134. In addition, a contact mechanism 130 may be characterized by the type of contact body 132, e.g., a roller 140 or a pad (not shown). In this embodiment, the contact mechanism 130 is a compliant roller mechanism 142.

[0042] The compliant contact mechanism 134 guides the shaft 104 and accommodates potential inner diameter variation of the housing 106. This allows the tolerances on the inner surface 107 of the housing 106 and the shaft 104 to be relaxed and such components to be less expensive to manufacture while still providing a desired degree of precision in the movement of the shaft. For example, an actuator 100 without a compliant contact mechanism may have the inner diameter of the housing 106 and the outer diameter of the shaft 104 both be made to a tolerance of ±0.01 mm in order to provide a desired degree of precision in the extension/retraction functionality of the mechanical actuator. If the actuator 100 has a compliant contact mechanism 134, the tolerance of the inner diameter of the housing 106 may be relaxed to ±0.03 mm and the tolerance of the outer diameter of the shaft 104 may be, for example, set to a default machining tolerance since it is not a concern for the guide mechanism 102. The outermost surface 133 of the contact body 132 in the compliant contact mechanism 134 can move between multiple radial positions relative to the shaft 104 with respect to the center axis 128. The compliant contact mechanism 134 may have a compliant element 146, e.g., a coil spring 156. The compliant element 146 urges the contact body 132 radially outward, away from the shaft 104 and toward the inner surface 107 of the housing 106. The compliant element 146 can be preloaded differently depending on the application. In the application shown, the compliant element 146 may be sized and configured such that it is compressively loaded by between one and three pounds when the compliant contact mechanism 134 is installed within the mechanical actuator 100.

[0043] In FIG. 1, the compliant contact mechanism 134 is a compliant roller mechanism 142 with a contact body 132 that is a roller 140. The compliant element 146 in this embodiment is a coil spring 156. Other examples of compliant elements 146 include a cantilever beam, a plunger with a spring, a torsional spring, a tensional spring, compression spring, wave spring, an elastomeric material that forms the outermost part of the contact body 132, and other compliant mechanisms. In the embodiment shown in FIG. 1, the compliant roller mechanism 142 has two pins, a first pin 158 and a roller pin 154. In the embodiment shown, both the first pin 158 and the roller pin 154 are dowel pins. The first pin 158 pivotably connects the compliant roller mechanism 142 with the shaft 104 and has its position fixed relative to the shaft. The roller pin 154 may be connected to the roller mechanism arm 160 between the first pin 158 and the coil spring 156, although other configurations are contemplated as well, e.g., with the first pin being between the roller pin and the coil spring. The roller pin 154 rotatably supports the roller 140 relative to the roller mechanism arm 160. The coil spring 156 pushes the roller mechanism arm 160 outward and pushes the roller 140 toward the inner surface 107 of the housing 106 so that an outermost surface 133 of the roller is in contact with the inner surface 107 of the housing 106. As the shaft 104 translates along the translation axis 126, the outermost surface 133 of the roller 140 rolls along the inner surface 107 of the housing 106. The coil spring 156 compresses or expands to accommodate any variation in diameter along the inner surface 107 of the housing 106. Thus, the tolerances for the inner diameter of the housing 106 may be relaxed when compared to a similar mechanical guide without the compliant mechanism but offering the same precision.

[0044] The guide mechanism 102 has at least three contact mechanisms 130 each with a corresponding contact body 132. At least one of the contact mechanisms 130 is a compliant contact mechanism 134. At least two of the at least three contact mechanisms 130 are non- compliant contact mechanisms. For example, in an embodiment with three contact mechanisms 130, there is one compliant contact mechanism 134 and two non-compliant contact mechanisms. In another embodiment, the guide mechanism 102 may have four contact mechanisms. In such an embodiment, there may be two compliant contact mechanisms 134 and two non-compliant contact mechanisms. The four contact mechanisms may be arranged in a circular array and spaced equal angular distances apart. The two non-compliant contact mechanisms may be placed adjacent to each other. Each compliant mechanism may be placed opposite to a corresponding non-compliant contact mechanism. An embodiment with three contact mechanisms is shown in FIG. 2.

[0045] FIG. 2 shows a top cutaway view of a mechanical actuator 200 similar to the mechanical actuator shown in FIG. 1. The mechanical actuator 200 has a guide mechanism 202 with a shaft 204 and housing 206. The guide mechanism 202 has three contact mechanisms 230, each connected to the shaft 204 and having a contact body 232 in contact with an inner surface 207 of the housing 206. There is a radial gap 282 between an outer surface 205 of the shaft 204 and the inner surface 207 of the housing 206 where the multiple contact bodies 232 are in contact with the inner surface of the housing. In some embodiments, the radial gap 282 may exist along only part of the housing, such as a translation region (discussed further below). In some embodiments, the radial gap 282 may extend along the length of the housing 206. The three contact mechanisms 230 shown in FIG. 2 include a compliant contact mechanism 234 and two non-compliant contact mechanisms 236. Similar to FIG. 1, the contact mechanisms 230 in FIG. 2 are roller mechanisms which have rollers 240 as the contact bodies 232. The three contact mechanisms are arranged in a circular array and spaced equally distances apart. [0046] The roller mechanisms are connected to the shaft 204 and have the roller 240 rotatably supported by a corresponding roller pin 254. The rollers 240 rotate about corresponding roller axes 248. Each of the roller axes 248 is parallel to a corresponding reference axis 250 that is perpendicular to the shaft center axis 228. In some embodiments, the rollers 240 are made of rigid plastic, such as bearing-grade polyamide-imide or bearing grade polyether ether ketone. Rigid plastics and similar types materials are not considered to be “compliant” in the context of this disclosure.

[0047] As discussed above, the compliant contact mechanism 234 may have a compliant element (not shown) such as a spring (not shown). The non-compliant contact mechanisms 236 do not have such a compliant element and an outermost surface 233 of the corresponding contact body 232 is a fixed distance away from the shaft. The contact body 232 in the non- compliant contact mechanism 236 translates along the translation axis with the shaft 204 but does not translate radially relative to the shaft.

[0048] In the embodiment shown, the two non-compliant contact mechanisms 236 are non- compliant roller mechanisms. Each of the rollers 240 is rotatably supported by a corresponding roller pin 254. The roller pin 254 may, for example, be pressed into a hole or holes in the shaft 204. As the shaft 204 translates relative to the housing 206 the rollers 240 may roll along the inner surface 207 of the housing 206.

[0049] The three roller mechanisms may work together, along with the inner surface 207 of the housing 206, to act as a guide mechanism 202 to the mechanical actuator 200. As the shaft 204 translates along the translation axis, an outermost surface 233 of the rollers 240 for each of the roller mechanisms roll along the inner surface 207 of the housing 206. Due to the compliance provided by the compliant roller mechanism, the inner surface 207 may have any of a variety of diameters that the guide mechanism 202 may be able to accommodate without the possibility of gaps forming or excessive friction developing. This may prevent the shaft 204 from binding or seizing up as the shaft translates along the translation axis.

[0050] The compliant contact mechanism 234 allows other components in the guide mechanism 202 to have larger tolerances. For example, the translation region of the housing may be designed to have a larger inner diameter such that the radial gap 282 exists in the translation region. The radial gap 282 may be designed to have a larger tolerance since the compliant roller mechanism can accommodate a variety of different inner surface diameters. The translation region can be better seen in FIG. 1. The translation region 162 is a region between two planes, a first translation plane 164 and a second translation plane 166. The first translation plane 164 is defined by the contact points between the contact bodies 132 and the housing inner surface 107 when the shaft 104 has translated to a first limit. The second translation plane 166 is defined by the contact points between the contact bodies and the housing inner surface 107 when the shaft 104 has translated to a second limit. For the housing 206, the translation region 162 is the section of the housing that comes into contact with the contact bodies 232 of the contact mechanisms 230 during translation between the up and down positions. For example, when the full range of translation of a shaft 104 is 25 mm, e.g., the first translation plane 164 and second translation plane 166 are 25 mm apart, the translation region 162 will have a height of 25 mm. In another example, when the full range of translation of a shaft 104 is 13 mm, the translation region 162 will have a height of 13 mm.

[0051] In the embodiment shown, the inner diameter of the housing 206 may have an inner diameter of 25 mm and a tolerance of ±0.03 mm in the translation region. In other embodiments, the diameter may be less than 25 mm. In still some other embodiments, the diameter may be larger than 25 mm. The housing may be made of an aluminum-containing material, e.g., an aluminum alloy. In some embodiments, the material may be stiffer, such as steel. In some implementations, the thickness of the housing 206, particularly in the translation region, may be as low as 2.5 mm thick in some portions. In still some other implementations, the thickness of the housing 206 may be as low as .75 mm thick in some portions.

[0052] Each of the contact mechanisms 230 may be located within the housing 206 of the mechanical actuator 200. As shown in FIG. 2, the guide mechanism 202 has contact mechanisms 230 all within the housing 206 and use the inner surface 207 of the housing as surface guide. By having the contact mechanisms 230 located within the housing, the footprint of the mechanical actuator 200 may be reduced as compared, for example, with other types of linear guide systems. In fact, the mechanical actuator 200 may have the same form factor as mechanical actuators that feature sliding bearing surfaces with no compliance mechanisms in use. This may allow the mechanical actuators described herein to be swapped in for such mechanical actuators, allowing the mechanical actuators discussed herein to be used in place thereof with no appreciable modification of the surrounding equipment.

[0053] FIG. 3 depicts another embodiment of a mechanical actuator 300 with a guide mechanism 302. In this embodiment, the mechanical actuator 300 may have a shaft 304, housing 306, an end cap 310, bellows 312 and a drive system (not shown). The mechanical actuator 300 may be used to lift a pin 314 in a semiconductor processing chamber (not shown). A top end of the bellows 312 may attach and be fixed to the end cap 310, while the bottom end of the bellows may attach and be fixed to the translating shaft 304. As the shaft 304 translates along a translation axis 326, the shaft is guided by three contact mechanisms 330, only one of which is shown. The shown contact mechanism 330 is a compliant contact mechanism 334 with a compliant element 346 and a contact body 332. The compliant element 346 is a coil spring 356. The contact body 332 is a pad 368. An outermost surface 333 of the pad 368 is in contact with and slides along an inner surface 307 of the housing 306. In this embodiment, the other two contact mechanisms (not shown) are non-compliant contact mechanisms. The non- compliant contact mechanisms may each have a pad as their contact body 332. An outermost surface of each of the pads of the non-compliant contact mechanisms may be fixed in its radial position relative to the shaft 304.

[0054] Shown in FIG. 4 are views of an example compliant contact mechanism 434 and a non- compliant contact mechanism 436 that may be used in the guide mechanism 302 in FIG. 3. Each of the contact mechanisms 430 has a pad 468 as the contact body 432. In the compliant contact mechanism 434, the pad 468 is in contact with an inner surface 407 of a housing 406. Interposed between the pad 468 and a shaft 404 is a compliant element 446, a coil spring 456. The compliant element 446 allows an outermost surface 433 of the contact body 432 to move radially with respect to a center axis 428 of the shaft 404. The compliant element 446 may accommodate for variations to an inner diameter of the housing 406.

[0055] The non-compliant contact mechanism 436 shown in FIG. 4 has a pad 468 that is pinned into the shaft 404 by a first pin 458. An outermost surface 433 of the pad 468 is in contact with the inner surface 407 of the housing 406. The outermost surface 433 of the pad may be fixed in its radial position relative to the shaft 404. As the shaft 404 translates, the pad 468 slides along the inner surface 407. The non-compliant contact mechanism 436 may be used to locate the shaft 404 relative to the housing 406 along an axis transverse to the center axis 428 of the shaft 404.

[0056] FIGS. 5-1 through 5-4 show examples of compliant contact mechanisms 534 each with a different compliant element 546. For each figure, each compliant contact mechanism has a roller 540 as a contact body 532. FIG. 5-1 shows a compliant contact mechanism 534 with a coil spring 556 as the compliant element 546, this is similar to the compliant element shown in FIG. 1 and FIG. 2. The coil spring 556 pushes a roller mechanism arm 560 away from a shaft 504 towards a housing (not shown). The roller mechanism arm 560 is attached to the shaft 504 by a first pin 558. The roller 540 is connected to the roller mechanism arm 560 by a roller pin 554. The first pin 558 and the roller pin 554 may be a dowel pin. As the coil spring 556 pushes the roller mechanism arm 560 outward, an outermost surface 533 of the roller 540 comes into contact with the housing. Variations in an inner diameter of the housing may be absorbed by the coil spring 556. [0057] FIG. 5-2 shows a compliant contact mechanism 534 with a cantilevered beam 570 as the compliant element 546. One end of the cantilever beam 570 may be attached to the shaft 504. The other end of the cantilever beam 570 may attach to the roller 540 by a roller pin 554. The cantilever beam 570 projects the roller 540 radially outwards away from the shaft 504 so that an outermost surface 533 of the roller is in contact with a housing (not shown). In some embodiments, the cantilevered beam 570 is flexible to control the force that roller 540 applies to the housing (not shown). Similar to above, the cantilever beam 570 may absorb variations to an inner diameter of the housing.

[0058] FIG. 5-3 shows a compliant contact mechanism 534 with a roller 540 and an elastomeric material 572 as the compliant element 546. The elastomeric material 572 wraps around a surface of the roller 540. The elastomeric material 572 becomes an outermost surface 533 of the contact body 532. For example, the elastomeric material 572 may be an elastomeric O-ring that encircles the roller 540 like a tire. The roller 540 is rotatably supported relative to a shaft 504 by a roller pin 554. The elastomeric material 572 is in contact with an inner surface of a housing. In this case, the roller 540 is radially fixed relative to the shaft 504 and will translate along a translation axis with the motion of the shaft. The elastomeric material 572 may expand and compress to accommodate any variations to an inner diameter of the housing. The variations to the inner diameter may be absorbed by the elastomeric material 572 when the material compresses, expands, or deforms in any other way.

[0059] FIG. 5-4 shows a compliant contact mechanism 534 with a plunger 574 and a coil spring 556 as the compliant element. The plunger 574 is fixed to a shaft 504 on a first end and is connected to a roller 540 through a roller pin 554 on a second end. The coil spring 556 within the plunger 574 urges an outermost surface 533 of the roller 540 outward away from the shaft 504 towards an inner surface of a housing. Variations in an inner diameter of the housing may be absorbed by the coil spring 556.

[0060] FIG. 6 shows an example of semiconductor processing tool 690 with a mechanical actuator 600 with a guide mechanism used in a semiconductor processing chamber 676. Inside the semiconductor processing chamber 676 is a pedestal 680 and an edge ring 678, which may be a ring-like structure that may be used to tune aspects of semiconductor processing near a wafer’s edge. Multiple mechanical actuators 600 may be provided, each of which may lift a corresponding pin 614. The pins 614 are in contact with a bottom surface of the edge ring 678 and may raise and lower the edge ring 678 responsive to actuation of the mechanical actuators. In some embodiments, similar mechanical actuators 600 and pins 614 may be used to lift a substrate such as a semiconductor wafer. For example, the pins 614 may pass through the pedestal or a chuck and lower and lift a wafer onto and off of the pedestal or chuck. In another example, the mechanical actuator 600 and pins 614 may be used with an aligner to lift a wafer onto and off the aligner.

[0061] The mechanical actuator 600 is partially outside the semiconductor processing chamber and partially inside. The housing 606 is outside and attaches to the bottom of the semiconductor processing chamber 676. An O-ring is used to seal the connection so that the semiconductor processing chamber 676 may be kept at a subatmospheric pressure environment. As described above, a bellows within the chamber attaches to a translating shaft. The bellows allows components of the mechanical actuator 600 within the bellows to be at the same pressure as the semiconductor processing chamber 676. Mechanical actuator 600 components outside of the bellows including part of the translating shaft, a drive system, and each of the contact mechanisms used to guide the shaft remain in atmosphere pressure.

[0062] In some embodiments, the apparatuses described herein may include a controller that is configured to control various aspects of the apparatus in order to perform the techniques described herein. For example, in Figure 6, the semiconductor processing tool 60090 may include a controller 684 (which may include one or more physical or logical controllers) that is communicatively connected with and that controls some or all of the operations of a processing chamber. The controller 684 may include one or more memory devices 686 and one or more processors 688.

[0063] In some implementations, the controller 684 is part of an apparatus or a system, which may be part of the above-described examples. Such systems or apparatuses can include semiconductor processing equipment, including a processing tool or tools, chamber or chambers, a platform or platforms for processing, and/or specific processing components (a gas flow system, a substrate heating unit, a substrate cooling unit, etc.). These systems may be integrated with electronics for controlling their operation before, during, and after processing of a semiconductor wafer or substrate. The electronics may be referred to as the “controller,” which may control various components or subparts of the system or systems. The controller 684, depending on the processing parameters and/or the type of system, may be programmed to control any of the processes disclosed herein, including causing the mechanical actuator 100 to translate along a the translation axis, the lifting of pins, the delivery of processing gases, temperature settings (e.g., heating and/or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, positional and operation settings, wafer transfers into and out of a tool and other transfer tools and/or load locks connected to or interfaced with a specific system.

[0064] Broadly speaking, the controller 684 may be defined as electronics having various integrated circuits, logic, memory, and/or software that receive instructions, issue instructions, control operation, enable cleaning operations, enable endpoint measurements, and the like. The integrated circuits may include chips in the form of firmware that store program instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and/or one or more microprocessors, or microcontrollers that execute program instructions (e.g., software). Program instructions may be instructions communicated to the controller in the form of various individual settings (or program files), defining operational parameters for carrying out a particular process on or for a semiconductor wafer or to a system. The operational parameters may, in some embodiments, be part of a recipe defined by process engineers to accomplish one or more processing operations during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and/or dies of a wafer.

[0065] The controller 684, in some implementations, may be a part of or coupled to a computer that is integrated with, coupled to the system, otherwise networked to the system, or a combination thereof. For example, the controller may be in the “cloud” or all or a part of a fab host computer system, which can allow for remote access of the wafer processing. The computer may enable remote access to the system to monitor current progress of fabrication operations, examine a history of past fabrication operations, examine trends or performance metrics from a plurality of fabrication operations, to change parameters of current processing, to set processing operations to follow a current processing, or to start a new process. In some examples, a remote computer (e.g., a server) can provide process recipes to a system over a network, which may include a local network or the Internet. The remote computer may include a user interface that enables entry or programming of parameters and/or settings, which are then communicated to the system from the remote computer. In some examples, the controller 684 receives instructions in the form of data, which specify parameters for each of the processing operations to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of tool that the controller is configured to interface with or control. Thus, as described above, the controller 684 may be distributed, such as by comprising one or more discrete controllers that are networked together and working towards a common purpose, such as the processes and controls described herein. An example of a distributed controller for such purposes would be one or more integrated circuits on a chamber in communication with one or more integrated circuits located remotely (such as at the platform level or as part of a remote computer) that combine to control a process on the chamber.

[0066] As noted above, depending on the process operation or operations to be performed by the apparatus, the controller 684 might communicate with one or more of other apparatus circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout a factory, a main computer, another controller, or tools used in material transport that bring containers of wafers to and from tool locations and/or load ports in a semiconductor manufacturing factory.

[0067] It is to be understood that the phrases “for each <item> of the one or more <items>,” “each <item> of the one or more <items>,” or the like, if used herein, are inclusive of both a single-item group and multiple-item groups, i.e., the phrase “for ... each” is used in the sense that it is used in programming languages to refer to each item of whatever population of items is referenced. For example, if the population of items referenced is a single item, then “each” would refer to only that single item (despite the fact that dictionary definitions of “each” frequently define the term to refer to “every one of two or more things”) and would not imply that there must be at least two of those items. Similarly, the term “set” or “subset” should not be viewed, in itself, as necessarily encompassing a plurality of items — it will be understood that a set or a subset can encompass only one member or multiple members (unless the context indicates otherwise).

[0068] The use, if any, of ordinal indicators, e.g., (a), (b), (c)... or the like, in this disclosure and claims is to be understood as not conveying any particular order or sequence, except to the extent that such an order or sequence is explicitly indicated. For example, if there are three steps labeled (i), (ii), and (iii), it is to be understood that these steps may be performed in any order (or even concurrently, if not otherwise contraindicated) unless indicated otherwise. For example, if step (ii) involves the handling of an element that is created in step (i), then step (ii) may be viewed as happening at some point after step (i). Similarly, if step (i) involves the handling of an element that is created in step (ii), the reverse is to be understood. It is also to be understood that use of the ordinal indicator “first” herein, e.g., “a first item,” should not be read as suggesting, implicitly or inherently, that there is necessarily a “second” instance, e.g., “a second item.”

[0069] The term “between,” as used herein and when used with a range of values, is to be understood, unless otherwise indicated, as being inclusive of the start and end values of that range. For example, between 1 and 5 is to be understood to be inclusive of the numbers 1, 2, 3, 4, and 5, not just the numbers 2, 3, and 4. [0070] It should be appreciated that all combinations of the foregoing concepts (provided such concepts are not mutually inconsistent) are contemplated as being part of the inventive subject matter disclosed herein. In particular, all combinations of claimed subject matter appearing at the end of this disclosure are contemplated as being part of the inventive subject matter disclosed herein. It should also be appreciated that terminology explicitly employed herein that also may appear in any disclosure incorporated by reference should be accorded a meaning most consistent

[0071] It is to be further understood that the above disclosure, while focusing on a particular example implementation or implementations, is not limited to only the discussed example, but may also apply to similar variants and mechanisms as well, and such similar variants and mechanisms are also considered to be within the scope of this disclosure.

Claims

CLAIMS What is claimed is:

1. An apparatus comprising: a housing; a shaft located at least partially within the housing; a drive system configured to cause the shaft to translate relative to the housing and along a translation axis substantially parallel to a center axis of the shaft responsive to receipt of one or more control signals; and three or more roller mechanisms, wherein: each of the roller mechanisms is connected to and translates with the shaft and has a roller with an outer surface that is in contact with an inner surface of the housing, at least one of the three or more roller mechanisms is a compliant roller mechanism, each compliant roller mechanism including at least one compliant element configured such that at least a portion of the outer surface of the roller of that compliant roller mechanism is movable between multiple radial positions relative to the shaft and with respect to the center axis, and at least two of the three or more roller mechanisms are non-compliant roller mechanisms that do not include the compliant element of the compliant roller mechanism.

2. The apparatus of claim 1 wherein the at least one compliant element of each compliant roller mechanism is configured to press the roller of that compliant roller mechanism against the inner surface of the housing with a force between one pound and three pounds.

3. The apparatus of claim 1 or 2, wherein the compliant element is a spring.

4. The apparatus of claim 1 or 2, wherein the compliant element is a cantilever beam.

5. The apparatus of claim 1 or 2, wherein the compliant element is an elastomeric material that provides the outer surface of the roller in the compliant roller mechanism.

6. The apparatus of claim 3, wherein at least one of the at least one compliant roller mechanisms further includes a plunger, wherein: the plunger is configured to translate along a radial axis relative to the shaft and is urged radially outward by the spring, and the plunger supports the roller of that compliant roller mechanism relative to the shaft.

7. The apparatus of any of claims 1 through 6, wherein each of the rollers is configured to rotate about a corresponding roller axis, the corresponding roller axis parallel to a corresponding reference axis perpendicular to the center axis of the shaft.

8. The apparatus of claim 7, wherein each roller mechanism has a corresponding dowel pin configured to rotatably support the roller of that roller mechanism.

9. The apparatus of any of claims 1 through 8, wherein each roller is made of plastic.

10. The apparatus of claim 9, wherein the plastic is selected from the group consisting of a bearing grade polyamide-imide and a bearing grade polyether ether ketone (peek).

11. The apparatus of any of claims 1 through 10, wherein the housing is made of aluminum-containing material.

12. The apparatus of any of claims 1 through 11, wherein the housing has an inner diameter of 25 mm or less.

13. The apparatus of claim 12, wherein: the housing has a radial thickness in directions perpendicular to the shaft center axis less than or equal to 2.5 mm in at least a portion of a translation region of the housing, the translation region of the housing is between a first plane and a second plane, the first plane is a plane defined by a first group of contact points between each of the rollers and the inner surface of the housing when the shaft is at a first limit of its translation, and the second plane is a plane defined by a second group of contact points between each of the rollers and the inner surface of the housing when the shaft is at a second limit of its translation.

14. The apparatus of any of claims 1 through 13, wherein an inner diameter of the housing has a tolerance of ±0.03 mm.

15. The apparatus of any of claims 1 through 14, wherein the rollers of the roller mechanisms are arranged in a nominally circular array about a shaft center axis.

16. The apparatus of any of claims 1 through 15, wherein there are no more than three roller mechanisms.

17. The apparatus of claim 15, wherein there are exactly four roller mechanisms, two roller mechanisms adjacent to one another are non-compliant roller mechanisms and the other two roller mechanisms are compliant roller mechanisms.

18. The apparatus of any of claims 1 through 17, wherein the shaft is configured to translate relative to the housing by at least 25 mm along the translation axis.

19. The apparatus of any of claims 1 through 17, wherein the shaft is configured to translate relative to the housing by at least 13 mm along the translation axis.

20. The apparatus of any of claims 1 through 19, wherein the drive system includes a motor connected to a lead screw interfaced with a lead screw nut, and the shaft is coupled to the lead screw nut.

21. The apparatus of any of claims 1 through 20, further comprising a bellows and an end cap, the end cap fixed relative to the housing and connected with a first end of the bellows and the shaft attached to a second end of the bellows.

22. The apparatus of claim 21 further comprising a lift pin, the lift pin attached to the shaft and having a lift pin center axis that is aligned with the center axis of the shaft.

23. The apparatus of claim 22, wherein the pin is made of aluminum oxide.

24. The apparatus of claim 21 or 22, further comprising a semiconductor processing chamber, a pedestal, and an edge ring; wherein: the housing is mounted so as to be fixed with respect to the semiconductor processing chamber; the pin is extendable so that when the pin is extended, the edge ring is lifted.

25. The apparatus of any of claims 1 through 24, further comprising a radial gap, the radial gap has a gap distance in directions perpendicular to the shaft center axis between an outer surface of the shaft and the inner surface of the housing in at least a portion of a translation region of the housing, the translation region of the housing is between a first plane and a second plane, the first plane is a plane defined by a first group of contact points between each of the rollers and the inner surface of the housing when the shaft is at a first limit of its translation, and the second plane is a plane defined by a second group of contact points between each of the rollers and the inner surface of the housing when the shaft is at a second limit of its translation.

26. An apparatus comprising: a housing; a shaft located at least partially within the housing; a drive system configured to cause the shaft to translate relative to the housing and along a translation axis substantially parallel to a center axis of the shaft responsive to receipt of one or more control signals; and three or more contact mechanisms, wherein: each of the contact mechanisms is connected to and translates with the shaft and has a contact body with an outer surface that is in contact with an inner surface of the housing, at least one of the three or more contact mechanisms is a compliant contact mechanism, each compliant contact mechanism including at least one compliant element configured such that at least a portion of the outer surface of the contact of that compliant contact mechanism is movable between multiple positions along an axis perpendicular to the translation axis and relative to the shaft, and at least two of the three or more contact mechanisms are non-compliant roller mechanisms that do not include the compliant element of the compliant contact mechanism.