EP2021874A1

EP2021874A1 - Chucks for reticles and other planar bodies

Info

Publication number: EP2021874A1
Application number: EP07744174A
Authority: EP
Inventors: Scott c/o Nikon Corporation COAKLEY; Douglas C. c/o Nikon Corporation WATSON; W.T. c/o Nikon Corporation NOVAK; Alton H. c/o Nikon Corporation PHILLIPS
Original assignee: Nikon Corp
Current assignee: Nikon Corp
Priority date: 2006-05-19
Filing date: 2007-05-21
Publication date: 2009-02-11
Also published as: KR20090018916A; TW200807171A; WO2007136123A1; JP2009537966A

Abstract

Devices are disclosed for holding and moving a planar body such as a reticle (25) as used, for example, in microlithography. An exemplary device includes a stage (12) and a body chuck. The stage has a movable support surface. A proximal region (18a, 18b) of a first membrane (16a, 16b) is mounted to the support surface (17a, 17b). A distal region (20a, 20b) of the first membrane extends from the support surface and is coupled to the chuck (22a, 22b) such that the first membrane at least partially supports the chuck. The chuck includes a surface from which multiple pins (44) extend. The surface is situated at the distal region. The pins are arrayed to contact and support a respective region of the body. The pin arrangement is configured such that, during movements of the chuck imparted by the support surface, body slippage relative to the pins due to forces caused by the movement is substantially uniform at each pin.

Description

DESCRIPTION

CHUCKS FOR RETTICLES AND OTHER PLANAR BODIES

FIELD

This disclosure pertains to, inter alia, microlithography, which is a key imaging technology used in the manufacture of semiconductor micro-devices, displays, and other products having fine structure that can be fabricated by processes that include microlithographic imprinting. More specifically, the disclosure pertains to devices for holding a reticle or other planar body.

Priority is claimed on U.S. Provisional Application No. 60/801,866, filed on May 19, 2006, the content of which are incorporated herein by reference.

BACKGROUND In a typical projection microlithography system, the pattern to be projected onto the surface of an exposure-sensitive substrate is defined by a "reticle," sometimes called a "mask." In the microlithography system the reticle is mounted on a stage that is capable of undergoing fine and highly accurate movements as required during the lithographic exposure. While mounted on the reticle stage, the reticle is illuminated by a radiation beam (e.g. , a beam of deep-ultraviolet or vacuum-ultraviolet light). As the beam propagates downstream from the reticle, the beam carries an aerial image of the illuminated pattern. This downstream beam, called a "patterned beam" or "imaging beam," passes through a projection-optical system that conditions and shapes the patterned beam as required to form a focused image of the pattern on the surface of an exposure-sensitive lithographic substrate (e.g., a resist-coated semiconductor wafer). For exposure, the substrate also is mounted on a respective movable stage called a

"substrate stage" or "wafer stage."

For holding the reticle (usually horizontally) during the making of lithographic exposures, the reticle stage is equipped with a "reticle chuck" mounted to a moving surface of the reticle stage. The reticle chuck holds the reticle in a suitable manner for imaging while avoiding damage to the delicate reticle. For example, some reticle chucks hold the reticle by applying a vacuum force to the reticle. Other reticle chucks hold the reticle by electrostatic or Lorentz-force attraction. In microlithography systems in which the radiation beam is transmitted through the reticle, the reticle chuck is usually configured to hold (to "chuck") the reticle around the periphery (or at least along two opposing sides) of the reticle, thereby leaving the patterned regions of the reticle unsupported. Due to the mass of the reticle, the unsupported middle region of the reticle tends to sag due to gravity. The sag deforms the reticle and can degrade the imaging performance of the microlithography system if not corrected or compensated for in some manner.

Two important measures of performance of a microlithography system are overlay and image quality. Image quality encompasses any of various parameters such as image resolution, fidelity, sharpness, contrast, and the like. "Overlay" pertains to the accuracy and precision with which a current image is placed relative to a target location for the image. For example, proper overlay requires that the image be in registration with a previously formed, underlying structure on the substrate.

The deformed shape of a chucked reticle has a direct impact on overlay and image quality. If reticle sag is inevitable, then the ideal deformed shape is at most second-order (parabolic) about the scanning axis (y-axis). Making appropriate adjustments to downstream optics {e.g. , the projection-optical system) can compensate for this kind of reticle deformation, but each reticle usually deforms differently from another reticle, and it is impractical to adjust the downstream optics each time a different reticle is chucked.

With a chucked reticle, localized factional forces are established at regions of contact of the reticle with the chuck, and these frictional forces are key to retaining position of the reticle on the chuck during movements of the reticle stage. But, these frictional forces may not be sufficient to overcome localized shear stresses between the reticle and chuck during accelerations and decelerations of the reticle stage. These shear stresses can cause slip of the reticle relative to the chuck. Also, after an acceleration or deceleration the reticle and chuck may not, as a result of reticle slip, return to their original respective shapes and positions relative to each other. In such an event residual stresses will be produced in the reticle and chuck, which may cause adverse reticle distortions during scanning motions of the reticle stage during lithographic exposure. Another consequence of reticle slip is a non-repeatable change in the relative position between the reticle and interferometers that are used for determining reticle position. This change directly affects overlay accuracy.

These issues conventionally have been addressed by attempts to control and minimize thermal and mechanical distortion over the entire reticle stage. However, as successive generations of microlithography systems require increasingly higher stage accelerations, and as overlay specifications continue to tighten, the limitations of this approach have become more apparent.

One approach for solving this problem is discussed in U.S. Patent No. 6,956,222 to Gilissen et ah, in which the reticle rests on a "pimple plate" extending over a table with a gap between the pimple plate and the table. The pimple plate is made of a very rigid material (glass or ceramic) and comprises multiple bumps that contact the reticle. The reticle is held on the pimple plate by electrostatic attraction. The pimple plate is held on the membranes by electrostatic attraction. The underside of the pimple plate is supported by support pins mounted to the table. The pimples have high stiffness in all three (x, y, z) directions. Unfortunately, during accelerations and decelerations of the reticle stage holding a reticle, the reticle exhibits an unacceptable amount of slip relative to the pimple plate, and the pimple plate exhibits an unacceptable amount of slip relative to the membranes.

Another approach for solving this problem is discussed in U.S. Patent No. 6,480,260 to Donders et al. , incorporated herein by reference. According to the '260 patent, two opposing side (flanking) regions (relative to the y-direction, the scanning direction) of the reticle are held on the reticle stage with the aid of respective "compliant members" arranged parallel to each other. In a preferred embodiment, each compliant member has a strip-like configuration that extends lengthwise along the respective side region of the reticle and along the respective side region of the reticle stage. One lateral side region of the compliant member is mounted to the respective side region of the reticle stage and the other lateral side region of the compliant member extends in a cantilever manner from the respective edge region of the reticle stage. Extending along the full length of the cantilevered side region of each compliant member and projecting upward are short walls that encircle and define a respective "vacuum space." The walls and vacuum space collectively define respective reticle "chucks." The corresponding under-side of the reticle actually rests on the top edges ("lands") of the walls that collectively serve as respective "chuck surfaces." Evacuating the vacuum space holds the reticle on the chuck surfaces. Whereas the compliant members exhibit compliance in the z-direction and yield somewhat to the shape of the reticle, they nevertheless have high stiffness in the x-y directions, as do the walls. At least three pins extend between the underside of the chucks and the top surface of the reticle stage (i.e., two pins beneath one chuck and one pin beneath the other chuck). Also, one or more "pins" can be located in the vacuum spaces to provide additional support for the chucked regions of the reticle; these configurations are called "pin chucks." During accelerations and decelerations of the reticle stage supporting a reticle chucked in this manner, the reticle still exhibits an unacceptable amount of slip relative to the chuck surfaces.

SUMMARY In view of the foregoing summary of conventional reticle chucks, it would be advantageous if the reticle could be chucked on the reticle stage with further reduced (or completely eliminated) slip of the reticle relative to the chuck surfaces, while still providing kinematic support for the reticle. Achieving such a goal would eliminate a substantial source of overlay errors and the like during lithographic exposures.

According to a first aspect, devices are provided for holding and moving a planar body, such as a reticle. An embodiment of the device comprises a stage and a body chuck. The stage has a movable support surface. The device includes a first membrane including a proximal region and a distal region. The proximal region is coupled to the support surface. The distal region extends from the support surface and is coupled to the body chuck such that the first membrane at least partially supports the body chuck. The body chuck comprises a surface and multiple pins. The surface is situated at the distal region of the first membrane. The pins extend relative to the surface and are arrayed on the surface to contact and support a respective portion of the body relative to the surface. The pins are arrayed so that, during movements of the body chuck imparted by corresponding movement of the support surface, slippage of the body relative to the pins due to forces caused by the movement is substantially uniform at each pin.

In certain embodiments of the device summarized above, the stage has first and second support surfaces spaced apart from each other (but that desirably move in a synchronous manner). The body chuck comprises a first chuck portion and a second chuck portion, and the first membrane comprises a first membrane portion mounted to and extending from the first support surface and a second membrane portion mounted to and extending from the second support surface. The first chuck portion is mounted to a distal region of the first membrane portion, and the second chuck portion is mounted to a distal region of the second membrane portion. The body chuck can comprise at least one vacuum chuck, such as for a reticle. In this and other configurations, the body chuck can comprise walls extending from the surface. The walls desirably define, in cooperation with the surface and a portion of the body contacting the body chuck, a vacuum cavity.

The walls have respective lands, and the pins have respective top surfaces. The top surfaces (and optionally at least one of the lands) collectively define a chuck surface that contacts and at least partially supports the body whenever the body is being held by the device. The top surfaces of the pins (and optionally at least one of the lands) contact an under-surface of the body. The walls can be integral with the surface. At least one of the walls can be made of a different material than the surface and mounted to the surface.

The pins can be arranged to extend in at least one longitudinal column in a scanning direction of the body chuck as moved by the support surface. The pins can be arranged in multiple longitudinal columns. The pins can have substantially identical respective stiffness or variable stiffness. The device can include a second membrane that can comprise the surface from which the pins extend. The second membrane can have a substantially uniform thickness or have a variable thickness. The second membrane can be made of a material such as, but not limited to, invar, ZERODUR^®. The pins can be integral with, and made of the same material as, the second membrane. In embodiments including a second membrane, at least one of the walls can be made of the same material as the second membrane.

According to another aspect, devices are provided for holding and moving a reticle. An embodiment of such a device comprises a stage comprising first and second movable support surfaces. The device also comprises a reticle chuck mounted to the support surfaces. The reticle chuck comprises first and second chuck portions. Each chuck portion comprises a respective first membrane having a respective first region and a respective second region. The first regions are mounted to the respective first and second support surfaces such that the second regions extend toward each other from the first and second support surfaces. The first and second chuck portions are mounted to the respective second regions. Each chuck portion comprises a respective surface (which can be of a second membrane mounted to the first membrane or part of the first membrane) and respective walls and free-standing pins extending from the surface. The surface and respective walls collectively define a respective vacuum cavity whenever a respective region of a reticle is situated on the chuck portion. The walls provide respective lands that can be contacting or non-contacting lands, wherein a contacting land contacts the under-surface of the reticle and a non-contacting land does not. At least the pins (and optionally at least one land) contact and support the respective region of the reticle. The pins are configured and arranged so that, during a movement of the reticle chuck by the stage, slippage of the reticle relative to the pins (and any contacting lands) due to shear forces caused by the movement occurs with substantial uniformity at each pin and contacting land.

Alternative embodiments concern various configurations of pins, pin columns, walls, lands, vacuum cavities, etc., as summarized above. In certain embodiments the tops of the pins (and any contacting lands) in each chuck portion collectively define respective chuck surfaces situated in a plane and configured to hold respective portions of the reticle.

The foregoing and additional features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. IA is a plan view of a first representative embodiment of a kinematic reticle chuck, as an exemplary device for holding and moving a planar body.

FIG. IB is an elevational section along the line B-B in FIG. IA. FIG. 2 depicts a second-order deformation of the reticle as chucked, exhibiting a parabolic profile about the scanning axis (y-axis).

FIG. 3 A is a schematic elevational view of a portion of a kinematic reticle chuck according to a fourth representative embodiment, in which the pins are not all the same length. FIG. 3B is a schematic elevational view of a portion of an alternative configuration of the kinematic reticle chuck shown in FIG. 3 A.

DETAILED DESCRIPTION

The following description is set forth in the context of representative embodiments that are not intended to be limiting in any way. In the following description, certain terms may be used such as "up," "down,"

"upper," "lower," "horizontal," "vertical," "left," "right," and the like. These terms are used, where applicable, to provide some clarity of description when dealing with relative relationships. But, these terms are not intended to imply absolute relationships, positions, and/or orientations. For example, with respect to an object, an "upper" surface can become a "lower" surface simply by turning the object over. Nevertheless, it is still the same object.

In this disclosure, the term "reticle" is used to denote a pattern-defining object (pattern master) used in microlithography and related techniques. Another term frequently used in microlithography to denote the pattern master is "mask," and it will be understood that "reticle" as used herein encompasses masks and other pattern masters used in microlithography.

First Representative Embodiment A first representative embodiment of a kinematic reticle chuck 10 is depicted in

FIGS. 1 A-IB. FIG. IA is a plan view of the x-y plane, wherein the y-direction is the scanning direction. Shown are left and right portions 14a, 14b of the reticle stage 12, each presenting a respective support surface 17a, 17b. The portions 14a, 14b extend parallel to each other in the y-direction and oppose each other in the x-direction. Attached to the support surfaces 17a, 17b are respective flexible members (each termed a "first membrane" herein) 16a, 16b. Each first membrane 16a, 16b has a first lateral region 18a, 18b attached to the respective support surface 17a, 17b of the reticle stage 12, and a second lateral region 20a, 20b extending in a cantilever manner from the respective portion 14a, 14b. Hence, the first lateral regions 18a, 18b are respective "proximal" regions (relative to the support surfaces 17a, 17b, respectively) of the first membranes 16a, 16b, and the second lateral regions 20a, 20b are respective "distal" regions (relative to the support surfaces 17a, 17b, respectively) of the first membranes 16a, 16b. Mounted to the upward-facing surface of each second lateral region 20a, 20b is a respective vacuum chuck 22a, 22b. The vacuum chucks 22a, 22b support a reticle 25. As shown in FIG. IB between each vacuum chuck 22a, 22b and the respective second lateral region 20a, 20b is a respective spacer 24a, 24b serving to elevate the vacuum chucks (in the z-direction) slightly from the upper surfaces of the respective second lateral regions.

The vacuum chuck 22a is mounted to the upper surface of the spacer 24a. The vacuum chuck 22a comprises a base (also called a "second membrane" or "web") 28 from which walls 30, 32 project in the z-direction.

The walls 30, 32 have respective upper surfaces 34, 36, called "lands." (Although the figure shows all the lands at a uniform height above the surface of the second membrane 28, this is not intended to be limiting. ^" The lands 34, 36 of this embodiment all have substantially the same height above the second membrane 28 and collectively define a "chuck surface," extending in the x-y direction, on which the reticle is placed (FIG. IB). The reticle 25, second membrane 28, and walls 30, 32 collectively define a vacuum cavity 33 that is evacuated through a port 46 that extends through the second membrane 28. Reducing the pressure in the vacuum cavity 33 urges the reticle against the lands 34, 36.

This embodiment solves a key problem that is experienced by conventional reticle chucks, namely the problem of slippage due to unequal shear forces at each point of contact of the vacuum chucks with the reticle. In this embodiment, if the reticle 25 were subject to an acceleration or deceleration having a magnitude sufficient to cause the reticle to slip on the vacuum chucks 22a, 22b, the slippage point (magnitude of shear stress) is substantially the same at each such point of contact of the reticle with the vacuum chucks.

Exemplary materials from which to fabricate the first membranes 16a, 16b and second membranes 28, 28b are invar, and ZERODUR^® (a brand of glass ceramic from Schott AQ Germany). For less demanding applications, any of several metals alternatively could be used. Particularly desirable materials have extremely low coefficients of thermal expansion, and the foregoing list is similar to a list of candidate materials for fabricating reticles. The reticle chucks can be made of any of these materials, and can be made of the same material as the first membranes or of a different material.

The walls 30, 32 and lands 34, 36 need not be made of the same material as the second membrane 28.

The walls 30, 32 in this embodiment have respective lands 34, 36 that are all in the same x-y plane (as the tops of the pins), which is achieved in this embodiment by configuring all the walls 30, 32 with identical height relative to the upper surface of the second membrane 28. But, having all the lands in the same x-y plane in this embodiment is not intended to be limiting. In alternative embodiments, such as described later below, at least one of the walls (e.g., the outboard wall) is shorter than other of the walls (e.g., the inboard wall), thereby placing the land of the shorter wall below the x-y plane of the pin tops and leaving a gap between the land and the underside of the reticle.

The walls 30, 32 in this embodiment are continuous with each other, but this is not intended to be limiting. Vacuum chucks having at least one shorter wall or a wall with at least one gap along its length form "leaky" seals for the vacuum cavity 33. The first lateral regions 18a, 18b of the first membranes 16a, 16b can be attached to their respective support surfaces 17a, 17b of the reticle stage by any of various suitable means. Exemplary means includes adhesive means.

In the embodiment described above, each vacuum chuck 22a, 22b comprised multiple columns of free-standing pins 44 (two columns are shown). A reticle placed on a reticle chuck according to this embodiment likely will experience gravity-induced sag, which is largely inevitable with an object supported in this manner. See FIG. 2, which depicts an ideal deformed-reticle shape. The "ideal" deformed shape is one that is, at most, second-order about the scanning axis (y-axis). As already discussed, two important measures of performance of a microlithography system are overlay and imaging. The deformed shape of a chucked reticle has a direct impact on overlay and imaging. But, if the deformed shape is, at most, second-order (parabolic) about the scanning axis, then downstream optics can be readily adjusted to compensate the effects of the deformation. This embodiment achieves this goal. In addition, although different reticles have different respective flatness, this embodiment of a reticle chuck kinematically supports the reticle so that differing reticle flatness does not affect the deformed shape when the reticle is chucked. Also, this embodiment holds the reticle securely even as the reticle stage undergoes repeated accelerations and decelerations in the y-direction. Thus, overlay errors are minimized.

Second Representative Embodiment

Various embodiments are configured so that the ratios of shear stresses to normal contact stresses are substantially equal at all points of contact of the reticle with the vacuum chucks. It alternatively is possible to distribute the shear stresses between the reticle and vacuum chucks so as to have the stresses vary from point to point in a desired manner. The instant embodiment is directed to achieving this variability by controllably varying the shear/bending stiffness of the pins. For example, changing the size (length) of the pins can produce corresponding changes in their shear/bending stiffness. Examples are shown in FIGS. 3 A and 3B. In FIG. 3 A a portion of the reticle 25, the reticle-stage portion 14, and the first membrane 16a are shown, along with a vacuum chuck 120. The vacuum chuck 120 comprises shorter distal walls 122, taller proximal walls 124, and free-standing pins 126a, 126b, 126c extending upward from the surface of a stepped second membrane (web) 128. Note that the second membrane 128 can be simply an extension of the first membrane 16a. By way of example, the pins 126a, 126b, 126c vary in height from 0.25 to 2.5 mm. The reticle 25 rests not only on the tops of the pins 126a, 126b, 126c but also on lands 130a, 130b defined by the walls 122, 124, respectively. The lands 130a, 130b effectively enclose the region beneath the chucked portion of the reticle 25 to define a vacuum cavity 132.

In FIG. 3B depicts an alternative configuration in which the walls 142, 144 of a vacuum chuck 140 are shorter than the free-standing pins 146a, 146b, 146c. The walls 142, 144 provide lands 148a, 148b that effectively provide a vacuum "seal" to the under-surface of the reticle 25 to define a vacuum cavity 150. The base 152 is stepped to accommodate the different lengths of pins 146a- 146c. Note also the variations in web thickness.

This representative embodiment can allow higher reticle acceleration, without reticle slip, by distributing the shear stresses between the reticle and the reticle chuck in a predetermined manner.

Whereas the disclosure was set forth in the context of various representative embodiments, it will be understood that the scope of the invention is not limited to those embodiments. On the contrary, the invention is intended to encompass all modifications, alternatives, and equivalents falling within the spirit and scope of the invention, as defined by the appended claims.

Claims

1. A device for holding and moving a planar body, the device comprising: a stage having a movable support surface; a body chuck; a first membrane including a proximal region and a distal region, the proximal region being coupled to the support surface and the distal region extending from the support surface and being coupled to the body chuck such that the first membrane at least partially supports the body chuck; the body chuck comprising a surface and multiple pins extending relative to the surface and being arrayed on the surface to contact and support a respective portion of the body relative to the surface and distal region; and the pins being arrayed so that, during movements of the body chuck imparted by corresponding movement of the support surface, slippage of the body relative to the pins due to forces caused by the movement is substantially uniform at each pin.

2. The device of claim 1, wherein the body chuck comprises at least one vacuum chuck.

3. The device of claim 1, wherein the body chuck comprises walls extending from the surface, the walls defining, in cooperation with the surface and a portion of the body contacting the body chuck, a vacuum cavity.

4. The device of claim 3, wherein: the walls have respective lands; the pins have respective top surfaces; and at least the top surfaces of the pins collectively define a chuck surface that contacts and at least partially supports the body whenever the body is being held by the device.

5. The device of claim 4, wherein at least one of the lands, along with the top surfaces, collectively define a chuck surface that contacts and at least partially supports the body whenever the body is being held by the device.

6. The device of claim 4, wherein the top surfaces contact an under-surface of the body.

7. The device of claim 4, wherein the top surfaces and at least one land contact an under-surface of the body.

8. The device of claim 1, wherein the pins are arranged to extend in at least one longitudinal column in a scanning direction of the body chuck as moved by the support surface.

9. The device of claim 8, wherein the pins are arranged in multiple longitudinal columns.

10. The device of claim 1 , wherein the pins are shaped identically.

11. The device of claim 1 , wherein the pins have substantially identical respective stiffness.

12. The device of claim 1, wherein the pins have variable stiffness.

13. The device of claim 1 , wherein the first membrane has a substantially uniform thickness.

14. The device of claim 1 , wherein the first membrane has a variable thickness.

15. The device of claim 1, wherein: the body chuck further comprises a second membrane comprising the surface relative to which the pins extend; the second membrane is coupled to the distal region; and the pins contact and support the respective portion of the body relative to the second membrane.

16. The device of claim 15, wherein: the stage has a first and a second support surfaces spaced apart from each other; the body chuck comprises a first chuck portion and a second chuck portion; the first membrane comprises a first membrane portion mounted to and extending from the first support surface and a second membrane portion mounted to and extending from the second support surface; the first chuck portion is mounted to a distal region of the first membrane portion; and the second chuck portion is mounted to a distal region of the second membrane portion.

17. The device of claim 15, wherein the body chuck comprises at least one vacuum chuck.

18. The device of claim 15, wherein the body chuck comprises walls extending from the second membrane, the walls defining, in cooperation with the second membrane and a portion of the body contacting the body chuck, a vacuum cavity.

19. The device of claim 18, wherein: the walls have respective lands; the pins have respective top surfaces; and at least the top surfaces of the pins collectively define a chuck surface that contacts and at least partially supports the body whenever the body is being held by the device.

20. The device of claim 19, wherein the top surfaces and at least one of the lands collectively define the chuck surface.

21. The device of claim 19, wherein at least the top surfaces contact an under-surface of the body.

22. The device of claim 20, wherein the top surfaces and at least one of the lands contact an under-surface of the body.

23. The device of claim 18, wherein the walls are integral with the second membrane.

24. The device of claim 15, wherein the pins are arranged to extend in at least one longitudinal column in a scanning direction of the body chuck as moved by the support surface.

25. The device of claim 24, wherein the pins are arranged in multiple longitudinal columns.

26. The device of claim 15, wherein the pins are shaped identically.

27. The device of claim 15, wherein the pins have substantially identical respective stiffness.

28. The device of claim 15, wherein the pins have variable stiffness.

29. The device of claim 15, wherein the second membrane has a substantially uniform thickness.

30. The device of claiml 5, wherein the second membrane has a variable thickness.

31. The device of claim 15, wherein the second membrane is made of a material selected from the group consisting of invar and ZERODUR^®.

32. The device of claim 15, wherein the pins are integral with, and made of the material as, the second membrane.

33. The device of claim 15, wherein at least one of the walls is made of the same material as the second membrane.

34. A device for holding and moving a reticle, the device comprising: a stage comprising first and second movable support surfaces; and a reticle chuck mounted to the support surfaces, the reticle chuck comprising first and second chuck portions, each chuck portion comprising a respective first membrane having a respective first region and a respective second region; the first regions being mounted to the respective first and second support surfaces such that the second regions extend toward each other from the first and second support surfaces; the first and second chuck portions being mounted to the respective second regions; each chuck portion comprising respective walls and free-standing pins extending from a respective surface, the surface and walls collectively defining a respective vacuum cavity whenever a respective region of a reticle is situated on the chuck portion; in each chuck portion, at least the pins contacting and supporting the respective region of the reticle; and the pins being configured and arranged so that, during a movement of the reticle chuck by the stage, slippage of the reticle relative to the pins due to shear forces caused by the movement occurs with substantial uniformity at each pin.

35. The device of claim 34, wherein the free-standing pins are arranged in multiple columns on the surface in each chuck portion.

36. The device of claim 34, wherein at least one wall of each chuck portion provides a contacting land.

37. The device of claim 36, wherein the at least one contacting land and tops of the pins in each chuck portion collectively define respective chuck surfaces situated in a plane and configured to hold respective portions of the reticle.

38. The device of claim 34, wherein the pins in at least one chuck portion are shaped substantially identically.

39. The device of claim 34, wherein the pins have substantially identical respective stiffness.

40. The device of claim 34, wherein at least some of the pins have variable stiffness.

41. The device of claim 34, wherein the first membranes have substantially uniform thickness.

42. The device of claim 34, wherein the first membranes have variable thickness.

43. The device of claim 34, wherein each chuck portion comprises a respective second membrane comprising the respective surface.

44. The device of claim 43, wherein the second membranes have substantially uniform thickness.

45. The device of claim 43, wherein the second membranes have variable thickness.

46. A process system, comprising: a process device; and a device, as recited in claim 1, for holding and moving a planar body relative to the process device.

47. A microlithography system, comprising: an imaging optical system configured to imprint a pattern, defined on a reticle, on a lithographic substrate; a reticle stage situated relative to the imaging optical system and comprising a movable support surface; and a reticle chuck mounted to the support surface, the reticle chuck comprising at least one chuck portion; the chuck portion comprising a first membrane including a proximal region and a distal region, the proximal region being coupled to the support surface and the distal region extending from the support surface and being coupled to the chuck portion such that the first membrane at least partially supports the reticle chuck; the chuck portion comprising a surface and multiple pins extending from the surface, the surface being situated at the distal region of the first membrane, the pins being arrayed on the surface to contact and support a respective portion of the reticle relative to the surface; and the pins being arrayed so that, during movements of the reticle chuck imparted by corresponding movement of the support surface, slippage of the reticle relative to the pins due to forces caused by the movement is substantially uniform at each pin.

48. A microelectronic device, fabricated by a process including at least one microlithography step performed with a microlithography system as recited in claim 47.

49. A microlithography process, performed using a microlithography system as recited in claim 47.

50. A microlithography system, comprising: an imaging optical system configured to imprint a pattern, defined on a reticle, on a lithographic substrate; a reticle stage situated relative to the imaging optical system and comprising first and second movable support surfaces; and a reticle chuck mounted to the support surfaces and comprising first and second chuck portions, each chuck portion comprising a respective first membrane having a respective first region and a respective second region; the first regions being mounted to the respective first and second support surfaces such that the second regions extend toward each other from the first and second support surfaces; the first and second chuck portions being mounted to the respective second regions; each chuck portion comprising a respective surface and respective walls and free-standing pins extending from the surface, the surface and respective walls collectively defining a respective vacuum cavity whenever a respective region of a reticle is situated on the chuck portion; at least the pins being configured to contact and support the respective region of the reticle; and the pins being configured and arranged so that, during a movement of the reticle chuck by the stage, slippage of the reticle relative to the pins due to shear forces caused by the movement occurs with substantial uniformity at each pin.

51. A microelectronic device, fabricated by a process including at least one microlithography step performed with a microlithography system as recited in claim 50.

52. A microlithography process, performed using a microlithography system as recited in claim 50.