Two-axis motion from linear actuator

Abstract

Various examples include a device to provide motion on at least two linear axes, wherein each of the linear axes is substantially orthogonal to each other. The apparatus may include a load table having a first actuator (e.g., a modified linear motor) coupled to the load table to provide linear motion to the load table in a first direction. A wide magnet set is coupled to or included as part of the first actuator. The wide magnet set has a width sufficient to allow movement of the load table in a second direction substantially orthogonal to the first direction without compromising operation of the linear motor. A second actuator is also coupled to the load table to provide the linear motion in the second direction substantially within the magnetic field constraint of the wide magnet set. Other systems, apparatuses, and devices are also disclosed.

Description

[0001] Priority Claim

[0002] This application claims the benefit of priority of U.S. Provisional Patent Application Serial No. 63 / 385,356, filed on November 29, 2022, and entitled "TWO-AXIS-MOTION FROM A LINEAR ACTUATOR", and U.S. Provisional Patent Application Serial No. 63 / 545,815, filed on October 26, 2023, and entitled "BELL-CRANK ASSEMBLY TO PROVIDE DIRECTIONAL MOTION", each of which is hereby incorporated by reference in its entirety. Technical Field

[0003] The disclosed subject matter generally relates to the field of movement of equipment and devices in various physical directions, such as three-dimensional printing and other applications, as well as lithography, substrate inspection, and metrology tools for semiconductor and related industries (e.g., flat panel display and solar cell production facilities). More specifically, in various embodiments, the disclosed subject matter relates to a two-axis linear actuator for transporting various types of inspection and metrology tools in two or more directions, including the x, y, z, and θ directions relative to a substrate located below the linear actuator. In other embodiments, the disclosed subject matter relates to a linear motion system for controlling the height of a load stage in the z direction (e.g., above a substrate located below the load stage) with substantially no tilt or other θ rotation of the load stage. Background Art

[0004] Current linear motion systems typically use separate motion and bearing systems to provide positioning in two or more directions. These linear motion systems generally include a linear motion x-axis stage and a separate linear motion y-axis stage mounted to the x-axis stage to provide x-y positioning capabilities. Additionally, a θ rotation stage is often mounted to the combined x-axis and y-axis stages to provide movement of a load (e.g., components of a metrology tool, a substrate, an optical system, etc.) in the x, z, and θ rotation directions.

[0005] In addition, current types of linear motion systems typically encounter problems in maintaining straight-line and in-line movement of a load stage (e.g., various types of optical metrology equipment and other devices can be mounted to these load stages) at the speeds encountered in high-speed operations, such as in metrology, alignment, characterization, and / or inspection equipment.

[0006] What is needed is a lightweight device that provides positioning of a load without using a separate linear motion x-axis stage and a separate linear motion y-axis stage. Various embodiments of the disclosed subject matter can provide motion on at least two axes (e.g., linear or rotational) within an actuator (e.g., a single linear actuator). The same single linear actuator can also provide motion in the θ rotational direction.

[0007] In addition, various embodiments disclose a device for providing motion to a load stage as the load stage passes over a substrate (e.g., a semiconductor substrate, a flat panel display, a panel, a wafer, etc.), the load stage being configured to hold, for example, an optical component, such as for various types of equipment, such as metrology, overlay, characterization, and / or inspection equipment. Thus, in various embodiments, the disclosed subject matter is configured to move the load stage in the z direction (e.g., a first direction) relative to the substrate with substantially no tilt or other θ rotation from a selected z height, while allowing other linear actuators to move the load stage in the x direction and the y direction (e.g., a second direction and a third direction, respectively). SUMMARY OF THE INVENTION

[0008] This document particularly describes a device for providing motion on at least two axes, wherein each of the linear axes is substantially orthogonal to each other. In various embodiments, the device may further include a θ rotation stage. The device may include a load stage having a first actuator (e.g., a modified linear motor) coupled to the load stage to provide linear motion to the load stage in a first direction. A wide magnet set is coupled to the first actuator or is included as part of the first actuator. The wide magnet set has a width sufficient to allow movement of the load stage in a second direction, the second direction being substantially orthogonal to the first direction. A second actuator is also coupled to the load stage to provide the linear motion in the second direction substantially within the constraint of the wide magnet set. As described in more detail herein, the second actuator is arranged to provide at least one of linear motion and rotational motion to the load stage in the second direction by moving the load stage in the second direction using, for example, one or more linear actuators or one or more voice coil motors.

[0009] Additionally, various embodiments disclosed herein can provide motion to a load stage as the load stage passes over a substrate (e.g., a semiconductor substrate, a flat panel display, a panel, a wafer, etc.), the load stage being configured to hold, for example, an optical component, such as for various types of equipment, such as metrology, overlay, characterization, and / or inspection equipment.

[0010] In various embodiments, the disclosed subject matter is a device for providing motion along at least two linear axes, each of the at least two linear axes being substantially orthogonal to one another. The device includes a load stage. A first actuator is coupled to the load stage to provide linear motion to the load stage in a first direction. A wide magnet set is coupled within the first actuator. The wide magnet set has a width sufficient to permit movement of the load stage in a direction substantially orthogonal to the first direction. At least one second actuator is also coupled to the load stage to provide at least one of linear motion and rotational motion to the load stage in a second direction substantially orthogonal to the first direction.

[0011] In various embodiments, the disclosed subject matter is a device for providing motion along at least two linear axes, each of the at least two linear axes being substantially orthogonal to one another. The device includes a load stage having a mounting plate and a first linear motor configured to provide linear motion to the load stage in a first direction. The first linear motor includes a magnet set and a coil bearing plate. The coil bearing plate is coupled to the mounting plate of the load stage and is substantially surrounded by the magnet set on at least two sides. The coil bearing plate is arranged to move the load stage in at least a first direction via a magnetic field generated within the first linear motor. The application further includes at least one second actuator coupled to the load stage. The at least one second actuator is configured to provide at least linear motion to the load stage in a second direction substantially orthogonal to the first direction.

[0012] In various embodiments, the disclosed subject matter is a device for providing motion along at least two linear axes, each of the at least two linear axes being substantially orthogonal to one another. The device includes a first linear motor to provide linear motion in a first direction. The first linear motor includes a magnet set and a coil bearing plate. The coil bearing plate is substantially surrounded by the magnet set on at least two sides. The coil bearing plate is arranged to move via a magnetic field generated within the first linear motor in at least a first direction.

[0013] In various embodiments, the disclosed subject matter is configured to move a load stage in a z - direction (e.g., a first direction) relative to a substrate with substantially no tilt or other θ rotation from a selected z - height, while allowing other linear actuators to move the load stage in the x - direction and the y - direction (e.g., a second direction and a third direction, respectively).

[0014] In various embodiments, the disclosed subject matter is a device configured to provide motion to a load stage in a first direction while allowing motion of the load stage in second and third directions. The device includes: a shaft configured to apply torque to the load stage; one or more z-direction load stage actuators mechanically coupled to the shaft to adjust the height of the load stage above a workpiece. A motion actuator is mechanically coupled to the shaft and positioned adjacent to the one or more z-direction load stage actuators to apply a force to the shaft.

[0015] In various embodiments, the disclosed subject matter is a device configured to provide motion to a load stage in a first direction while allowing motion of the load stage in second and third directions, each of which directions is substantially orthogonal to each other. The device includes: a shaft configured to apply torque to the load stage; at least a pair of z-direction load stage actuators mechanically coupled to each other and mounted on opposite ends of the shaft, the at least a pair of z-direction load stage actuators configured to adjust the height of the load stage above a substrate; and a motion actuator located between the at least a pair of z-direction load stage actuators. The motion actuator is configured to apply a force to the shaft in a direction substantially transverse to the direction of the force applied to the load stage by the at least a pair of z-direction load stage actuators. A bell crank assembly is coupled between the motion actuator and the shaft. The bell crank assembly is configured to provide a force to the shaft to apply torque to the at least a pair of z-direction load stage actuators. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The various figures in the drawings merely illustrate example embodiments of the present disclosure and should not be considered as limiting its scope.

[0017] Figure 1 An example of a device arranged to move equipment and devices in various physical directions is shown, the device incorporating various embodiments of the disclosed subject matter;

[0018] Figure 2A An example of a perspective view of a modified version of a linear motor combined with an air bearing and a multi-axis motion system that can be used with a Figure 1 substrate inspection system is shown;

[0019] Figure 2B An example of a side elevation view of a multi-axis motion system of Figure 2A is shown;

[0020] Figure 3 An example of a side elevation view of Figure 2A and Figure 2B of a portion of a multi-axis motion system on which a load, such as an optical component of a substrate inspection or metrology system, can be mounted is shown;

[0021] Figure 4A shows a rear perspective view of a multi-axis motion system according to various embodiments; Figure 3 of;

[0022] Figure 4B shows a front perspective view of a multi-axis motion system according to various embodiments; Figure 3 of;

[0023] Figure 5A shows an example of a rear perspective view of an exemplary load stage incorporating various embodiments of the disclosed subject matter;

[0024] Figure 5B shows a top perspective view of a load stage incorporating various embodiments of the disclosed subject matter; Figure 5A of;

[0025] Figure 5C shows a front perspective view of a portion of a load stage incorporating various embodiments of the disclosed subject matter; Figure 5A of;

[0026] Figure 5D shows a top perspective view of a portion of a load stage that houses a motion actuator according to various embodiments of the disclosed subject matter; Figure 5A of;

[0027] Figure 5E shows Figure 5A a top perspective view of a portion of a load stage that indicates a motion actuator and a z-direction load stage actuator mounted transversely with respect to a linear actuator of the z-direction load stage actuator; and Figure 5D of;

[0028] Figure 6 shows a block diagram of an example of a machine on which any one or more of the techniques (e.g., methods) discussed herein can be executed. DETAILED DESCRIPTION

[0029] Various embodiments of the disclosed subject matter relate to a device for providing motion in at least two linear axes, where each of the linear axes is substantially orthogonal to each other. The device may include a load stage having a first actuator (e.g., a modified linear motor) coupled to the load stage to provide linear motion to the load stage in a first direction. A wide magnet assembly is coupled to or included as part of the first actuator. The wide magnet assembly has a width sufficient to permit movement of the load stage in a second direction that is substantially orthogonal to the first direction. A second actuator is also coupled to the load stage to provide the linear motion in the second direction substantially within the constraint of the wide magnet assembly. As described in more detail herein, the second actuator is arranged to provide at least one of linear motion and rotational motion to the load stage in the second direction by moving the load stage in the second direction using, for example, one or more linear actuators or one or more voice coil motors.

[0030] Various embodiments of the disclosed subject matter include the bell crank assemblies disclosed herein that coordinate the orthogonality and alignment of mechanisms providing two-axis motion. Thus, various examples herein describe a device for providing motion to a load stage as the load stage passes over a substrate (e.g., a semiconductor substrate, a flat panel display, a panel, a wafer, etc.), where the load stage is configured to hold, for example, an optical component for various types of equipment such as lithography, characterization, and / or inspection equipment. In various embodiments, the disclosed subject matter is configured to move the load stage in the z-direction relative to the substrate with substantially no tilt or other θ rotation from a selected z-height, while allowing other linear actuators to move the load stage in the x-direction and the y-direction.

[0031] Thus, the disclosed subject matter provides precise motion in at least two axes in various embodiments. Rotational motion, and thus tilt or twist motion (providing θ rotation), can also be applied to the load stage by using another linear actuator mounted close to the load stage, offset from the center of the load stage, or on an edge of the load stage.

[0032] Current two-axis linear motion systems typically use separate motion and bearing systems to provide positioning in two or more directions. These linear motion systems generally include a linear motion x-axis stage and a separate linear motion y-axis stage mounted to the x-axis stage to provide x-y positioning capabilities. Typically, each linear motion system in the current linear motion systems uses a separate linear electric motor in each of the orthogonal directions to generate a linear force along the length of the linear motor. Additionally, a θ rotation stage is often mounted to the combined x-axis and y-axis stages to provide movement of a load (e.g., components of a metrology tool, a substrate, an optical system, etc.) in the x-direction, y-direction, and θ rotation direction. Each of these separate motion stages can add significant weight and physical size to the current linear motion systems.

[0033] In various embodiments, the encoding of the direction of linear motion (e.g., a scan motion) can use a laser interferometer to determine the distance the load stage has moved. Multiple laser interferometers can be used to encode linear motion in two or more directions plus θ rotation. However, other non-contact and contact techniques can also be used to determine the encoded position. For example, a non-contact sensor can detect or measure a physical property, such as the distance to a target, without directly contacting the target. Examples of non-contact sensors include fiber optic sensors (using an optical fiber with a set of photodetectors at each end of the fiber and a light source attached to the target) and capacitive probe sensors (which rely on detecting a change in capacitance value to establish the position of the target being measured). Contact sensors include, for example, potentiometric position sensors (using a resistive track and a brush to measure the change in resistance due to the movement of the target) and inductive position sensors (using a contact probe placed in a coil where the magnetic field in the coil changes according to the position of the probe attached to the target).

[0034] A set of bearings is used to control the orientation of the load, and the set of bearings can be adjusted using one or more actuators. The adjustment of one or more actuators can laterally or rotationally change the orientation of the load, as described in detail below. As noted above, various types of position encoding systems and encoding techniques can be used to monitor the position of these actuators.

[0035] Generally speaking, the design of the disclosed subject matter produces a flat motion of the load and eliminates the need for stacked stages (e.g., an x-axis stage mounted to a y-axis stage (or z-axis stage) for two-dimensional motion, or a θ rotation stage mounted to a one-dimensional or two-dimensional linear axis stage). Additionally, with the two-axis motion design disclosed herein, the moving mass of the combined axes is reduced, thereby improving dynamic performance and throughput. Using a single air bearing system to define the motion planes in scan and θ can also improve the focus position of a load in, for example, metrology applications by increasing stability and predictability while also improving autofocus operation.

[0036] For example, referring now to Figure 1 , an example of a substrate inspection or metrology system 100 incorporating various embodiments of the disclosed subject matter is shown. Figure 1 It is shown as including a transfer bridge 101, a substrate stage platform 103, system legs 105, a substrate stage 107, and a y-direction substrate stage transport mechanism 109. Figure 1 It is also shown as including an example of a substrate inspection or metrology payload (such as an optical assembly 111) having an exemplary objective turret 115. The optical assembly 111 is mounted to an exemplary version of a modified linear motor 113. However, the optical assembly 111 is provided only as an example of a device or apparatus that can benefit from the disclosed subject matter. As noted above, the disclosed subject matter generally relates to the field of movement of equipment and devices in various physical directions, such as three-dimensional printing and other applications, as well as lithography, substrate inspection, and metrology tools for semiconductor and related industries (e.g., flat panel display, battery, and solar cell production facilities).

[0037] The transfer bridge 101 is arranged such that the optical assembly 111 can traverse above the substrate stage 107 in the ±x direction by the modified linear motor 113. The modified linear motor 113 also allows the optical assembly 111 to move in the ±z direction, as described in more detail below. However, as described herein, movement in the ±z direction does not require a separate second motor (e.g., a linear motor) as found in the prior art, which is orthogonally mounted to the first motor (e.g., another linear motor that moves in the ±x direction). In reading and understanding the disclosed subject matter, one of ordinary skill in the art will recognize that the modified linear motor 113 can be oriented in various positions. Thus, the modified linear motor 113 can be arranged to move any payload in, for example, the ±x direction and the ±y direction. Alternatively, the modified linear motor 113 can be arranged to provide movement in the ±y direction and the ±z direction. As described in more detail below with reference to Figure 4A and Figure 4B , a load stage actuator can be used to apply an optional θ rotation to the optical assembly 111 or other load stage.

[0038] The substrate stage 107 allows the substrate mounted thereon to move in the ±y direction under the transfer bridge 101. The y-direction substrate stage transport mechanism 109 can move the substrate stage 107 in the ±y direction substantially orthogonal to the direction in which the transfer bridge 101 is arranged. The y-direction substrate stage transport mechanism 109 is mounted to the substrate stage platform 103. In various embodiments, the substrate stage platform 103 can include a granite block resting on top of or supported by the system legs 105. In other embodiments, the substrate stage transport mechanism 109 can move the substrate stage 107 in a direction that is not orthogonal to the direction in which the transfer bridge 101 is arranged.

[0039] The optical component 111 is mechanically coupled to a load stage (not shown, but described below starting from Figure 2A ), which is mechanically coupled to a modified linear motor 113. Although the optical component 111 is shown as having a substrate inspection device (e.g., a substrate scanner) or a metrology device (e.g., an optical profiler), this configuration is provided only as an example to describe various ways in which the modified linear motor 113 can be used.

[0040] As described in more detail below, the modified linear motor 113 allows various types of devices to be mounted thereon. As Figure 1 shown in the exemplary embodiment of, the modified linear motor 113 is configured to move the optical component 111 in both the x-direction and the z-direction.

[0041] As partially pointed out above, current two-axis linear motion systems typically use separate motion and bearing systems to provide positioning in two or more directions. These linear motion systems typically include a linear motion x-axis stage and a separate linear motion y-axis stage mounted to the x-axis stage to provide x-y positioning capabilities. Other types of two-axis linear motion systems (such as a biaxial linear stepper motor (e.g., a Sawyer motor)) are linear motors having a plate capable of moving in the x-direction and the y-direction, but require magnets laid on the platen in two directions, or a grid pattern laid in a ferromagnetic material. Using the system described herein does not require magnets to be laid in two directions.

[0042] Compared to prior art systems, the disclosed subject matter has a first actuator (e.g., a modified linear motor) that is coupled to the optical component 111 to provide linear motion in a first direction (e.g., in the ±x direction) to the load stage (on which the optical component 111 is mounted). A wide magnet group is coupled to or included as part of the first actuator. The wide magnet group has a width sufficient to allow movement of the load stage in a second direction that is substantially orthogonal to the first direction (e.g., in the ±x direction). Thus, even when the coil moves in the orthogonal direction, the width of the magnet group (near the coil of the actuator) remains within the effective magnetic field. As described below, a second actuator is also coupled to the load stage to provide linear motion in the second direction substantially within the confines of the useful magnetic field region of the wide magnet group. The term "useful" can be considered to be within the turns of the coil such that the coil experiences the same or substantially the same magnetic field pattern regardless of its position within the wide magnet group.

[0043] Figure 2A Shown is a perspective view of a modified version of a combined linear motor and an air bearing multi-axis motion system 200 that can be used with Figure 1 the substrate inspection system of.Figure 2A shown as including a transfer bridge 201, a substrate stage platform 203, system legs 205, a substrate stage 207, a y-direction substrate stage transfer mechanism 209, and a modified linear motor 213A. Each of the components including the transfer bridge 201, the substrate stage platform 203, the system legs 205, the substrate stage 207, the y-direction substrate stage transfer mechanism 209, and the modified linear motor 213A may be the same as or similar to Figure 1 the similar components identified in Figure 2A also shown as including a bearing 215 (e.g., an air bearing or a vacuum air bearing) and a position encoder 219.

[0044] Figure 2A also shown as including a load stage 211 to which various types of substrate inspection and metrology equipment (such as Figure 1 the optical component 111) may be mounted. The load stage 211 is mechanically coupled to the modified linear motor 213A. Figure 2A also shown therein are z-direction load stage actuators 217A, 217B that may be used to apply a force to the load stage 211 in a vertical direction (e.g., the ±z direction), as described in more detail below. As described below with reference to Figure 4A and Figure 4B the load stage actuators 217A, 217B may also be used to apply an optional θ rotation to the load stage 211.

[0045] In this example, the z-direction load stage actuators 217A, 217B are arranged to move the load stage 211 (and any equipment mounted thereon) in the ±z direction. The load stage actuators 217A, 217B may be used, for example, to allow the movement of an optical component mounted on the load stage to move vertically (e.g., in the z direction) relative to the substrate stage 207 to allow the optical component to focus within a certain range.

[0046] The load stage actuators 217A, 217B may include, for example, various types of linear displacement transducers such as linear variable displacement transducers (LVDTs), or various types of pneumatic-hydraulic-magnetic and electric-operable slides (e.g., spring-loaded or double-acting), voice coil actuators, voice coil motors, etc. When actuated, the load stage actuators 217A, 217B generally move the load stage 211 within the ±z direction. Since a wide magnet set is coupled to or included as part of the first actuator, a second linear motor is not required to effect movement of the modified linear motor 213A in the z direction. The load stage 211 is coupled to a plate on which a coil set within the actuator is mounted (described below with reference to Figure 3described in detail), and moves within the track of the modified linear motor 213A. The wide magnet group within the modified linear motor 213A allows the coupled load stage 211 to move along the modified linear motor 213A while still allowing movement in the z direction within the modified linear motor 213A.

[0047] The substrate stage 207 (on which a substrate can be mounted or otherwise supported) is supported by bearings 215, thereby allowing mechanical stabilization of the substrate stage 207. In various embodiments, the bearings 215 can include low-friction supports such as, for example, air bearings or vacuum air bearings as noted above. An air bearing is a fluid bearing that uses a thin film of pressurized gas to provide a low-friction interface between surfaces. The load stage 211 is also supported by a plurality of preload bearings that are not shown Figure 2A in Figure 2B and Figure 3 but are discussed below with reference to

[0048] The position encoder 219 allows the multi-axis motion system 200 to determine the position of the load stage 211 (e.g., the lateral movement of the load stage 211 in the x direction). In various embodiments, the position encoder 219 can include, for example, various types of position sensors such as, for example, a laser interferometer. Although not explicitly shown, such a position encoder can also be used to determine the position of the load stage 211 in other directions (e.g., in the z direction).

[0049] Figure 2B shows Figure 2A a side elevation view 230 of an example of the multi-axis motion system 200. In addition to the components described above with reference to Figure 2A it is also shown as including a support portion 231A, a top-side preload bearing 235, a front-side preload bearing 233, a bottom-side preload bearing 237, and a rear-side preload bearing 239. Only one preload bearing of each of these preload bearings is shown in Figure 2B but these preload bearings are shown in more detail with respect to Figure 2A and Figure 4A and Figure 4B described below.

[0050] The front-side preload bearing 233 is shown as being mounted to the front frame portion 243 of the load stage 211, and the rear-side preload bearing 239 is mounted to the rear frame portion 241 of the load stage 211. The bottom-side preload bearing 237 is shown as being mounted to the bottom frame portion 245 of the load stage 211. In various embodiments, the bottom frame portion 245 may not be used.

[0051] The support portion 231 provides additional structural support for the transfer bridge 201. In addition to possible preload conditions, each of the preload bearings 233, 235, 237, 239 is supported by the transfer bridge 201 and may be the same as or similar to the bearing 215. For example, the front-side preload bearing 233 and the top-side preload bearing 235 maintain a fixed distance relationship between the load stage 211 and the transfer bridge 201. As shown in more detail with reference to Figure 3 Each of the load stage actuators 217A, 217B is coupled at its bottom end to a respective preload bearing in the top-side preload bearing 235 so as to remain in contact with the uppermost portion of the transfer bridge 201 regardless of the vertical position (e.g., z-direction) of the load stage 211. When the load stage actuators 217A, 217B push downward on the top-side preload bearing 235, each of the load stage actuators 217A, 217B is coupled to the load stage 211.

[0052] The rear-side preload bearing 239 also maintains a fixed distance relationship between the rear side of the load stage 211 and the transfer bridge 201. In addition, the rear-side preload bearing 239 is arranged as one or more latch bearings to limit the separation of the load stage 211 from the modified linear motor 213A. Thus, the combination of the front-side preload bearing 233, the top-side preload bearing 235, and the rear-side preload bearing 239 all serve to mechanically position and stabilize the load stage 211 relative to the transfer bridge 201.

[0053] In addition, in Figure 2B the bottom-side preload bearing 237 is shown in contact with the lowermost portion of the transfer bridge 201. However, the load stage actuators 217A, 217B may be positioned to lower the load stage 211 closer to the substrate stage 207. In various embodiments, when the load stage 211 is lowered, the bottom-side preload bearing 237 no longer contacts the transfer bridge 201. In other embodiments, the bottom-side preload bearing 237 may be, for example, spring-loaded and thus maintain contact with the transfer bridge 201 regardless of the z-position of the load stage 211.

[0054] Figure 3 A side elevation view 300 of a portion of the multi-axis motion systems 200, 230 of Figure 2A and Figure 2B is shown on which a load, such as an optical component of a substrate inspection or metrology system as described above, may be mounted. However, as noted above, the disclosed subject matter generally relates to the field of movement of equipment and devices in various physical orientations, such as three-dimensional printing and other applications, as well as lithography, substrate inspection, and metrology tools for semiconductor and related industries (e.g., flat panel display, battery, and solar cell production facilities). In addition to the components described above with reference to Figure 2A and Figure 2B ​Figure 3 is shown as including a load stage 211 mechanically coupled to a mounting plate 213C, which in turn is mechanically coupled to a coil bearing plate 213B within a modified linear motor 213A. The coil bearing plate 213B moves within a magnetic field generated within the modified linear motor 213A, thereby activating movement in the x direction (see Figure 2A ). The coil bearing plate 213B thus acts in a manner similar to a rotor in a rotary motor, while the magnetic field is generated in a manner similar to a stator in a rotary motor. The difference between the modified linear motor 213A and the rotary motor is that the modified linear motor 213A moves in a linear direction rather than in a rotary direction. However, since the modified linear motor 213A uses a wide magnet set (a magnet set with an increased amount of expected movement in the z direction in terms of width), a second linear stage substantially orthogonal to the first linear stage installation is not required.

[0055] Figure 4A A rear perspective view 400 of a multi-axis motion system 300 according to various embodiments is shown. Figure 3 is shown. Figure 4B A front perspective view 430 of a multi-axis motion system 300 according to various embodiments is also shown. By applying a downward force (in the negative z direction) to both of the load stage actuators 217A, 217B, the load stage 211 is raised away from the substrate stage 207 (see Figure 3 ). Thus, the load stage 211 is raised in the positive z direction. Conversely, by applying an upward force (in the positive z direction) to both of the load stage actuators 217A, 217B, the load stage 211 is lowered toward the substrate stage 207 (the load stage 211 moves in the negative z direction). Figure 2A )

[0056] By applying a downward force (in the negative z direction) to a single one of these actuators (e.g., the load stage actuator 217A), the load stage 211 will tilt in a clockwise direction (as viewed from the front of the load stage 211, as Figure 2A or Figure 4B depicts), thereby providing movement in the θ rotation direction to the load stage. In a similar manner, by applying a force to the load stage actuator 217B, the load stage 211 will tilt in a counterclockwise direction, again as viewed from the front of the load stage 211. In addition to applying a downward force to either one of the load stage actuators 217A, 217B individually, by applying opposite forces (one actuator moves upward in the positive z direction while the other actuator moves downward in the negative z direction), an additional amount of θ rotation tilt of the load stage 211 can be achieved.

[0057] In various types of systems, by using aspects of the disclosed subject matter, the moving mass of optical components (e.g., focus stages) can be significantly reduced or eliminated. Removing a second linear motion system as used by the prior art can reduce the dynamic mass by approximately 45 kilograms (100 pounds mass) or more. Additionally, using a single-bearing system as described herein to define the motion plane of an optical system can improve optical alignment, speed, and mechanical stability.

[0058] In various embodiments, the disclosed subject matter relates to an apparatus for providing z-direction motion to a load stage. In various embodiments, and as described in more detail below, a load stage that can be configured to move across a bridge (e.g., a granite bridge) positioned above a substrate under study is supported above the bridge by, for example, an air bearing. The load stage can be driven up (+z direction) and down (-z direction) by one or more z-direction load stage actuators (such as voice coil motors for applying a force to the load stage in the z direction). A motion actuator (e.g., a pneumatically operated bellows that operates in a linear direction in some embodiments) that acts as part of a bell crank assembly (described below with reference to Figures 5C to 5E is coupled to a shaft that is mounted to the motion actuator and between one or more z-direction load stage actuators, where the shaft is mechanically coupled to the z-direction load stage actuators at opposite ends of the shaft. However, as described in more detail below, only a single z-direction load stage actuator can be used. As shown in various figures in the drawings, only two z-direction load stage actuators are shown to better explain one embodiment of the disclosed subject matter. The shaft is configured to apply torque from the motion actuator to, for example, one or more z-direction load stage actuators, as described below.

[0059] The motion actuator applies a force to the shaft through the bell crank assembly, thereby applying torque to the shaft. The shaft in turn applies torque to one or more z-direction load stage actuators. The torque applied to one or more z-direction load stage actuators helps maintain or provide a substantially uniform force to the load stage (e.g., synchronized for vertical movement) and substantially prevents any θ rotation of the load stage (with respect to each side of the load stage, with respect to the axis about which the load stage will move in the x direction as defined in reference to Figure 1 Accordingly, the motion actuator applies a force to the shaft in a direction that is substantially transverse to the direction of the force applied to the load stage by one or more z-direction load stage actuators.

[0060] Accordingly, the disclosed subject matter limits the amount of rotation in the system, thereby limiting the tilt of the load stage. The disclosed bell crank assembly acts as a crank arm to adjust the relative height of the load stage above the substrate, so that the forces from each of the z-direction load stage actuators in the z-direction load stage actuator act on the load stage consistently with each other. The motion actuator bears most of the weight of the load stage, where the z-direction load stage actuator provides the desired height of the load stage above the substrate being inspected (e.g., for focusing of optical components mounted to the load stage).

[0061] In an embodiment, an optical encoder may be coupled to at least one end of the shaft and may be used to monitor the height of the load stage in the z-direction (e.g., based on sin(θ) of the rotation of the shaft). As noted above, the motion actuator that provides a force on the shaft acts substantially transverse to the direction of the z-direction load stage actuator acting on the load stage.

[0062] The disclosed subject matter can be used with any type of high-speed system where speed, stability, and linear motion are considerations. The system incorporates, for example, linear motors that are mechanically coupled to each other through a bell crank assembly to ensure that each motor provides a "lift" in the z-direction with high accuracy, with complete coordination between the z-direction load stage actuators.

[0063] Figure 5A A rear perspective view 500 of a load stage 511 incorporating various embodiments of the disclosed subject matter is shown. Figure 5A Is shown as including a first z-direction load stage actuator 517A, a second z-direction load stage actuator 517B, a motion actuator 515 positioned near at least one of the z-direction load stage actuators 517A, 517B, and a pivot point 509 about which each of the z-direction load stage actuators 517A, 517B may be provided with a limited rotational movement that is substantially about an imaginary line drawn from an approximate center position of the first z-direction load stage actuator 517A to the second z-direction load stage actuator 517B. The z-direction load stage actuators 517A, 517B allow the load stage 511 to be positioned at a height away from the substrate stage 207 (see Figure 2A and Figure 2B ) to allow, for example, focusing operations or other operations that may be mounted to the load stage 511. Although only two z-direction load stage actuators are shown, additional pairs of z-direction load stage actuators may be used. Additionally, a single z-direction load stage actuator may be used. As shown in the various figures in the drawings, only two z-direction load stage actuators 517A, 517B are shown to better explain the disclosed subject matter and an embodiment of the disclosed subject matter.

[0064] As described in more detail below, the motion actuator 515 applies a force in a direction that is substantially transverse to the direction of the forces applied by the z-direction platen actuators 517A, 517B in the ±z directions. The shaft ( Figure 5A is not shown, but is referenced below in Figures 5C to 5E shown and described).

[0065] Figure 5A is also shown as including a z-direction bearing 501 (e.g., an air bearing, Figure 5A only one of which is shown), an encoder 507A and an encoder reader 507B, a front-side bearing 503, a rear-side bearing 505, and a modified linear motor 513 (e.g., an x-direction motor). The motion actuator 515 also provides support in the approximate center of the platen 511 and also pre-loads the z-direction bearing 501. Each of the components including the platen 511, the z-direction platen actuators 517A, 517B, the motion actuator 515, and the modified linear motor 513 can be the same as or similar to the Figure 1 , Figure 2A and Figure 2B components described therein.

[0066] The rear-side bearing 505 can be used to maintain a fixed distance relationship between the rear side of the platen 511 and the transfer bridge 201 (see Figure 2A and Figure 2B ). Additionally, the rear-side bearing 505 is arranged as one or more latch bearings to restrict the platen 511 from disengaging from the modified linear motor 513. Thus, the combination of the front-side bearing 503, the z-direction bearing 501, and the rear-side bearing 505 are all used to mechanically position and stabilize the platen 511 relative to the transfer bridge 201 (see Figure 2A and Figure 2B ), while still allowing movement in each of the x-direction, y-direction, and z-direction.

[0067] The motion actuator 515 includes one of various types of linear or rotary actuators or other force-applying mechanisms, such as, for example, one capable of acting on a bell crank assembly ( Figure 5A is not shown, but is referenced below in Figures 5C to 5EA pneumatically or hydraulically operated actuator that applies a force to a part of the (shown and described). The z-direction load stage actuators 517A, 517B may also include, for example, a pneumatically or hydraulically operated actuator capable of applying a force to the corresponding z-direction bearing in the z-direction bearing 501. In a particular exemplary embodiment, the z-direction load stage actuators 517A, 517B include voice coil motors. In this example, each voice coil motor in the voice coil motors may receive an electrical signal from an electrical signal line (not shown) substantially simultaneously, such that the voice coil motors operate in unison to raise or lower the load stage 511. In the case where the z-direction load stage actuators 517A, 517B are, for example, pneumatically or hydraulically operated, a signal may be sent to, for example, an air reservoir or an oil-filled reservoir to provide appropriate fluid to the z-direction load stage actuators 517A, 517B, so as to operate the actuators substantially in unison to raise or lower the load stage 511. Once the z-direction load stage actuators 517A, 517B are actuated, the z-direction bearings 501 coupled to each of the z-direction load stage actuators 517A, 517B in turn apply a force to a part of, for example, the transfer bridge 201 (see Figure 2A and Figure 2B ) to raise or lower the load stage 511 in the z-direction (see, for example, Figure 5C ).

[0068] For example, when metrology and / or substrate inspection equipment (e.g., an optical component 111 such as Figure 1 ) is mounted on the load stage, the load stage 511 may provide a +z-direction movement using a force of approximately 1000 Newtons (approximately 225 pounds-force). In one embodiment, when the z-direction load stage actuators 517A, 517B include voice coil motors, the typical force provided by each voice coil motor may be approximately 250 Newtons (approximately 56 pounds-force) per motor. The interaction between these forces provided by the z-direction load stage actuators 517A, 517B and the motion actuator 515, which is used to stabilize the z-direction load stage actuators 517A, 517B and provide additional and uniform forces between these z-direction load stage actuators, is described in more detail below with reference to Figure 5C and Figure 5D . Additionally, various types of force application mechanisms may be used in addition to the disclosed subject matter described herein. Such force application mechanisms include, for example, springs (e.g., tensile, compressive, torsional), pneumatic cylinders, counterweights, etc.

[0069] In various embodiments, each of the z-direction bearing 501, the front-side bearing 503, and the rear-side bearing 505 may include, for example, an air bearing or a vacuum bearing. An air bearing is a fluid bearing that uses a thin film of pressurized gas to provide a low-friction interface between surfaces. The load stage 511 may also be supported by a plurality of preload bearings, which are not shown but are known in the relevant art.

[0070] The front bearing 503 provides a low-friction interface between the front side of the load stage 511 (since the front bearing 503 is mounted to the rear portion of the front portion of the load stage 511) and the front side portion of, for example, the transfer bridge 201 (see Figure 2A and Figure 2B ), regardless of the vertical position (e.g., z-direction) of the load stage 511. In a similar manner, the rear bearing 505 provides a low-friction interface between the rear side of the load stage (since the rear bearing 505 is mounted to the front portion of the rear portion of the load stage 511) and the rear side portion of, for example, the transfer bridge 201 (see Figure 2A and Figure 2B ), regardless of the vertical position (e.g., z-direction) of the load stage 511.

[0071] In various embodiments, the encoding of the z-height position is based on the rotation of a shaft (as shown and described below with reference to Figures 5C to 5E ), which is mechanically coupled between the motion actuator 515 and the z-direction load stage actuators 517A, 517B. The encoders 507A and encoder readers 507B can be mechanical or optical encoders, for example, that determine the rotation of the shaft. The z-height difference can be calculated based on, for example, the sine of the angular rotation of the shaft. Thus, the height difference by which the load stage 511 moves can be determined by applying, for example, trigonometric functions based on a circular-to-linear conversion. However, other non-contact and contact techniques can also be used to determine the overall z-height of the load stage 511.

[0072] Figure 5B A top perspective view 530 of the load stage 511 incorporating various embodiments of the disclosed subject matter is shown. Figure 5A Figure 5B Is shown as including force coupling links 519A (located on either side of the motion actuator 515, which is shown as an exemplary pneumatically operated bellows in Figure 5B ) and a shaft coupling mechanism 531 to couple the force generated by the motion actuator 515 to a shaft via the force coupling links 519A (each of which is described in more detail below with reference to Figure 5C and Figure 5D ). Additionally, Figure 5B A z-direction bearing 501 is shown that is mechanically coupled below each of the z-direction load stage actuators 517A, 517B.

[0073] Figure 5C A front perspective view 550 of a portion of the load stage 511 incorporating various embodiments of the disclosed subject matter is shown. Figure 5A Figure 5Cis shown as including a shaft 551, actuator connectors 553 each coupled to the shaft 551 from the z-direction load stage actuators 517A, 517B, a fixed linear actuator block 519B, and a movable linear actuator block 519C. The force coupling link 519A, the fixed linear actuator block 519B, and the movable linear actuator block 519C together form a bell crank assembly. Once activated, the bell crank assembly provides stability to the load stage 511 of the high-precision system. The motion actuator 515 is not shown in Figure 5C so as not to obscure the components of the bell crank assembly.

[0074] In operation, when the motion actuator 515 applies a force in the linear direction 560A from the fixed linear actuator block 519B towards the movable linear actuator block 519C, the force from the motion actuator 515 is transmitted through the force coupling link 519A and through the shaft coupling mechanism 531 to rotate the shaft 551, thereby generating a rotational direction 560B. The shaft 551 applies a torque to the actuator connector 553 to be applied to the corresponding z-direction load stage actuator among the z-direction load stage actuators 517A, 517B, which applies an additional force to lift the load stage 511 in the +z direction. Each of the z-direction load stage actuators 517A, 517B is allowed to rotate slightly about the corresponding pivot point 509 to reduce or eliminate any binding that might occur if the z-direction load stage actuators 517A, 517B were fixed and not allowed to rotate slightly.

[0075] By applying substantially the same force to each of the z-direction load stage actuators 517A, 517B, the torque applied by the shaft 551 also maintains substantially the same "lift" applied to each side of the load stage 511. Thus, in this example, the transmitted force applied by the motion actuator 515 supplements the lifting force provided by the z-direction load stage actuators 517A, 517B while preventing torsional movement of the load stage 511, which might otherwise occur if each of the z-direction load stage actuators 517A, 517B did not apply the same force substantially equally.

[0076] If the load stage 511 is lowered in the -z direction, the forces described above operate in substantially the same manner, where the forces are applied in directions opposite to those shown by the arrows of the linear direction 560A and the rotational direction 560B. Thus, as described above, after providing an external raise or lower signal, the motion actuator 515 provides an additional force to each of the z-direction load stage actuators 517A, 517B to act in unison. Thus, in addition to providing additional lift to the load stage 511 and lateral stabilization of the force, the motion actuator 515 can be considered a ballast system.

[0077] Initial calibration of the system can also be applied to adjust the amount of torque applied by the motion actuator 515 to each of the z-direction load stage actuators 517A, 517B. Adjusting the relative positions of each of the actuator couplings in the shaft coupling mechanism 531 and the actuator coupling 553 with reference to the position on the reference axis 551 can provide calibration to adjust the amount of torque applied to each of the z-direction load stage actuators 517A, 517B from the shaft 551 in a substantially equal manner.

[0078] In a particular exemplary embodiment, the shaft 551 can include a solid stainless steel rod having a diameter of about 35 mm and a length sufficient to span from one of the z-direction load stage actuators 517A, 517B to the other. In an embodiment, the shaft 551 can include other predetermined material types to provide sufficient torque based on the needs of a predetermined mass on the load stage 511. In an embodiment, a larger diameter shaft 551 can be selected such that the same torque can be applied, but through a hollow (e.g., tubular) version of the shaft 551.

[0079] Continuing to refer Figure 5B and Figure 5C , Figure 5D A top perspective view 570 of a portion of the load stage 511 according to various embodiments of the disclosed subject matter is shown, the portion accommodating the motion actuator 515 (although not shown in Figure 5A so as not to obscure the components of the bell crank assembly). As noted above, the bell crank assembly includes the force coupling link 519A, the fixed linear actuator block 519B, and the movable linear actuator block 519C. Figure 5D An additional view of the force applied in the linear direction 560A and the torque generated in the rotational direction 560B is provided. Figure 5D

[0080] Continuing to refer Figures 5B to 5D Figure 5E , Figure 5A A top perspective view 590 of a portion of the load stage 511 is shown, indicating the motion actuator 515 (although not shown in Figure 5D so as not to obscure the components of the bell crank assembly) and the z-direction load stage actuators 517A, 517B mounted laterally with respect to the motion actuator 515 of Figure 5B . As indicated by the force in the linear direction 560A applied by the motion actuator 515 (see Figure 5C and Figure 5D and Figure 5C ), the z-direction load stage actuators 517A, 517B apply forces in the ±z direction (see ). Thus, the force in the linear direction 560A is substantially transverse to the forces applied by the z-direction load stage actuators 517A, 517B.

[0081] Examples described herein may include, or may be operated on by, logic or multiple components or mechanisms. A circuit system is a collection of circuits implemented in a tangible entity that includes hardware (e.g., simple circuits, gates, logic, etc.). Circuit system membership may change over time and underlying hardware changes. A circuit system includes members that, when operating, can individually or in combination perform specified operations.

[0082] In one example, the hardware of a circuit system for controlling, for example, z-direction stage actuators 517A, 517B may be invariantly designed to implement a particular operation (e.g., hardwired). In one example, the hardware including the circuit system may include physical components with variable connections (e.g., execution units, transistors, simple circuits, etc.) that include computer-readable media that are physically modified (e.g., magnetically, electrically, such as via a change in a physical state or a transformation of another physical property) to encode instructions for a particular operation.

[0083] When connecting physical components, the underlying electrical properties of the hardware composition may change, for example, from an insulating property to a conductive property or vice versa. Instructions enable embedded hardware (e.g., execution units or loading mechanisms) to form members of a circuit system in the hardware via variable connections to perform portions of a particular operation when operating. In one example, any physical component may be used in more than one member of more than one circuit system. For example, in operation, an execution unit may be used in a first circuit of a first circuit system at one point in time and reused by a second circuit in the first circuit system or by a third circuit in a second circuit system at a different time.

[0084] The methods and techniques shown and described herein may be performed using a portion or all of the machine 600 as discussed below with respect to Figure 6 and shown in the accompanying drawings. Figure 6 An exemplary block diagram of a machine 600 is shown on which any one or more of the techniques (e.g., methods) discussed herein may be executed. In various examples, the machine 600 may operate as a stand-alone device or may be connected (e.g., networked) to other machines.

[0085] In a networked deployment, machine 600 can operate in a server-client network environment as a server machine, a client machine, or both. In one example, machine 600 can act as a peer machine in a peer-to-peer (P2P) (or other distributed) network environment. Machine 600 can be a personal computer (PC), a tablet device, a set-top box (STB), a personal digital assistant (PDA), a mobile phone, a web appliance, a network router, a switch or bridge, or any machine capable of executing instructions (sequentially or otherwise) that specify actions to be taken by that machine. Further, while only a single machine is shown, the term "machine" shall also be taken to include any collection of machines that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methods discussed herein, such as cloud computing, software as a service (SaaS), other computer cluster configurations.

[0086] Examples as described herein may include logic or a number of components or mechanisms, or may be operated by logic or a number of components or mechanisms. A circuit system is a collection of circuits implemented in a tangible entity that includes hardware (e.g., simple circuits, gates, logic, etc.). Circuit system membership may change over time and underlying hardware changes. A circuit system includes members that, when operating, can individually or in combination perform specified operations. In one example, the hardware of a circuit system can be immutably designed to perform a particular operation (e.g., hardwired). In one example, the hardware including a circuit system can include physically coupled components (e.g., execution units, transistors, simple circuits, etc.) that include a computer-readable medium that is physically modified (e.g., magnetically, electrically, such as by a change in physical state or transformation of another physical property, etc.) to encode instructions for a particular operation. When physically coupling the components, the underlying electrical properties of the hardware composition can, for example, change from insulating to conductive or vice versa. Instructions cause the embedded hardware (e.g., execution units or load mechanisms) to form members of the circuit system in the hardware via the variable connections to perform portions of the particular operation when operating. Thus, when the device is operating, the computer-readable medium is communicatively coupled to other components of the circuit system. In one example, any physical component can be used in more than one member of more than one circuit system. For example, in operation, an execution unit can be used in a first circuit of a first circuit system at one point in time and reused by a second circuit in the first circuit system or by a third circuit in a second circuit system at a different time.

[0087] A machine 600 (e.g., a computer system) may include a hardware-based processor 601 (e.g., a central processing unit (CPU), a graphics processing unit (GPU), a hardware processor core, or any combination thereof), a main memory 603, and a static memory 605, some or all of which may communicate with each other via an interconnect 630 (e.g., a bus). The machine 600 may also include a display device 609, an input device 611 (e.g., an alphanumeric keyboard), and a user interface (UI) navigation device 613 (e.g., a mouse). In one example, the display device 609, the input device 611, and the UI navigation device 613 may include at least a portion of a touchscreen display. The machine 600 may additionally include a storage device 620 (e.g., a drive unit), a signal generation device 617 (e.g., a speaker), a network interface device 650, and one or more sensors 615 (such as a global positioning system (GPS) sensor, a compass, an accelerometer, or another sensor type). The machine 600 may include an output controller 619, such as a serial controller or interface (e.g., a universal serial bus (USB)), a parallel controller or interface, or other wired or wireless (e.g., an infrared (IR) controller or interface, near field communication (NFC), etc.) that are coupled to communicate with or control one or more peripheral devices (e.g., a printer, a card reader, etc.).

[0088] The storage device 620 may include a machine-readable medium on which is stored a set or sets of data structures or instructions 624 (e.g., software or firmware) that embody or are utilized by any one or more of the techniques or functions described herein. The instructions 624 may also reside, completely or at least partially, within the main memory 603, within the static memory 605, within the mass storage device 607, or within the hardware-based processor 601 during execution by the machine 600. In an example, one or any combination of the hardware-based processor 601, the main memory 603, the static memory 605, or the storage device 620 may constitute a machine-readable medium.

[0089] Although the machine-readable medium is considered a single medium, the term "machine-readable medium" may include a single medium or multiple media (e.g., a centralized database or a distributed database, and / or associated caches and servers) configured to store one or more instructions 624.

[0090] The term "machine-readable medium" can include any medium that can store, encode, or carry instructions for execution by a machine 600 and cause the machine 600 to perform any one or more of the techniques in the technology of the present disclosure, or any medium that can store, encode, or carry data structures used by or associated with such instructions. Non-limiting examples of machine-readable media can include solid-state memory and optical and magnetic media. Thus, a machine-readable medium is not a transitory propagated signal. Specific examples of large-scale machine-readable media can include: non-volatile memory, such as semiconductor memory devices (e.g., electrically programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM)) and flash memory devices; magnetic or other phase change or state change memory circuits; magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks.

[0091] Instructions 624 can also be transmitted or received over a communication network 621 using a transmission medium via a network interface device 650 using any one of a variety of transmission protocols (e.g., Frame Relay, Internet Protocol (IP), Transmission Control Protocol (TCP), User Datagram Protocol (UDP), Hypertext Transfer Protocol (HTTP), etc.). Among other things, example communication networks can include local area networks (LANs), wide area networks (WANs), packet data networks (e.g., the Internet), mobile telephone networks (e.g., cellular networks), plain old telephone (POTS) networks, and wireless data networks (e.g., the Institute of Electrical and Electronics Engineers (IEEE) 802.22 standard family known as and the IEEE 802.26 standard family known as , the IEEE 802.25.4 standard family, peer-to-peer (P2P) networks. In one example, the network interface device 650 can include one or more physical jacks (e.g., Ethernet, coaxial, or telephone jacks) for connecting to the communication network 621 or one or more antennas. In one example, the network interface device 650 can include multiple antennas for wireless communication using at least one of single input multiple output (SIMO) technology, multiple input multiple output (MIMO) technology, or multiple input single output (MISO) technology. The term "transmission medium" should be understood to include any intangible medium that can store, encode, or carry instructions for execution by a machine 600 and includes digital or analog communication signals or other intangible media for facilitating the communication of such software.

[0092] After reading and understanding the disclosed subject matter, those of ordinary skill in the art will recognize that, although the disclosed subject matter is described in connection with a substrate inspection system or metrology system, no such limitation is intended. The use of the disclosed subject matter with a substrate inspection system or metrology system is provided to more easily illustrate possible uses of the disclosed subject matter. Accordingly, various aspects of the disclosed subject matter can be readily used in many different industries.

[0093] As used herein, the term "or" can be interpreted in an inclusive or exclusive sense. Additionally, based on reading and understanding the provided disclosure, those of ordinary skill in the art will understand other implementations. Further, those of ordinary skill in the art will readily understand that various combinations of the techniques and examples provided herein can all be applied in various combinations.

[0094] Throughout the specification, multiple instances may implement components, operations, or structures described as a single instance. Although the various operations are shown and described as separate operations, one or more of the various operations may be performed simultaneously, and unless otherwise stated, these operations are not required to be performed in the order illustrated. Structures and functions presented as separate components in an example configuration may be implemented as a combined structure or component. Similarly, structures and functions presented as a single component may be implemented as separate components. These and other variations, modifications, additions, and improvements fall within the scope of the subject matter described herein.

[0095] Additionally, although not explicitly shown, those skilled in the art will understand that each of the various arrangements, quantities, and numbers of elements may vary (e.g., the number of preload bearings or the number of load stage actuators). Further, each example shown and described herein is merely representative of one possible configuration and should not be considered as limiting the scope of the present invention.

[0096] Although the various implementations are discussed separately, these separate implementations are not intended to be considered as independent technologies or designs. As indicated above, each of the various parts may be interrelated, and each may be used alone or in combination with other implementations discussed herein. For example, although various implementations of methods, operations, systems, and processes have been described, these methods, operations, systems, and processes may be used alone or in various combinations.

[0097] Accordingly, many modifications and variations will be apparent to those of ordinary skill in the art in reading and understanding the disclosure provided herein. From the foregoing description, it will be apparent to those skilled in the art that functional equivalent methods and devices within the scope of the present disclosure, in addition to those methods and devices enumerated herein. Portions and features of some embodiments may be included in portions and features of other embodiments, or may replace portions and features of other embodiments. Such modifications and variations are intended to fall within the scope of the appended claims. Accordingly, the present disclosure is limited only by the terms of the appended claims and the full scope of equivalents to which those claims are entitled. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0098] The abstract of the specification is provided to allow the reader to quickly ascertain the essence of the technical disclosure. The abstract is submitted on the understanding that it will not be used to interpret or limit the claims. In addition, in the foregoing detailed description, it can be seen that for the purpose of simplifying the present disclosure, various features may be combined in a single embodiment. This method of disclosure should not be construed as limiting the claims. Accordingly, the following claims are hereby incorporated into the detailed description, where each claim stands on its own as a separate embodiment.

[0099] The description provided herein includes illustrative examples, devices, and apparatus embodying aspects of the subject matter described in the present invention. In this description, for purposes of explanation, numerous specific details are set forth in order to provide an understanding of the various embodiments of the subject matter discussed. However, it will be apparent to those of ordinary skill in the art that the various embodiments of the subject matter disclosed may be practiced without these specific details. In addition, well-known structures, materials, and techniques have not been shown in detail so as not to obscure the various illustrated embodiments. As used herein, the terms "about," "approximately," and "substantially" may refer to, for example, a value within ±10% of a given value or range of values.

[0100] The following numbered examples are specific embodiments of the disclosed subject matter

[0101] Example 1: One embodiment of the disclosed subject matter describes an apparatus for providing motion on at least two linear axes, each of the at least two linear axes being substantially orthogonal to each other. The apparatus includes a load stage. A first actuator is coupled to the load stage to provide linear motion to the load stage in a first direction. A wide magnet group is coupled within the first actuator. The wide magnet group has a width sufficient to allow movement of the load stage in a direction substantially orthogonal to the first direction. At least one second actuator is also coupled to the load stage to provide at least one of linear motion and rotational motion to the load stage in a second direction substantially orthogonal to the first direction.

[0102] Example 2: The apparatus according to Example 1, wherein the first actuator includes a linear motor.

[0103] Example 3: The apparatus according to any one of Example 1 or Example 2, wherein the at least one second actuator includes a voice coil motor.

[0104] Example 4: The apparatus according to any one of Example 1 or Example 2, wherein the at least one second actuator includes a linear motor.

[0105] Example 5: The apparatus according to any one of the foregoing embodiments, the apparatus further includes at least a first set of air bearings coupled to the load stage.

[0106] Example 6: The apparatus according to any one of the foregoing embodiments, the apparatus further includes at least one third actuator, the at least one third actuator being coupled near an edge of the load stage and configured to apply a force transverse to the edge to which the third actuator is coupled, the force providing rotational motion to the load stage.

[0107] Example 7: The apparatus according to any one of the foregoing embodiments, the apparatus further includes at least one rear preload bearing, the at least one rear preload bearing being mounted on a portion of the load stage that is opposite to the portion on which a component will be mounted to the load stage.

[0108] Example 8: The apparatus according to any one of the foregoing embodiments, the apparatus further includes at least one bottom preload bearing, the at least one bottom preload bearing being mounted on a lower portion of the load stage.

[0109] Example 9: The apparatus according to Example 8, wherein each of the at least one rear preload bearing and the at least one bottom preload bearing includes an air bearing.

[0110] Example 10: The device according to any one of the foregoing embodiments, the device further comprising a vacuum air bearing, the vacuum air bearing being mounted on a portion of the load stage, the portion being opposite to the portion on which the component will be mounted to the load stage.

[0111] Example 11: The device according to any one of the foregoing embodiments, the device further comprising at least one position encoding system to indicate the distance of the linear movement of the load stage in at least the first direction.

[0112] Example 12: An embodiment of the disclosed subject matter describes a device for providing movement along at least two linear axes, each of the at least two linear axes being substantially orthogonal to each other. The device includes a load stage having a mounting plate and a first linear motor configured to provide linear movement to the load stage in a first direction. The first linear motor includes a magnet assembly and a coil bearing plate. The coil bearing plate is coupled to the mounting plate of the load stage and is substantially surrounded by the magnet assembly on at least two sides. The coil bearing plate is arranged to move the load stage in at least the first direction via a magnetic field generated within the first linear motor. The device further includes at least one second actuator coupled to the load stage. The at least one second actuator is configured to provide at least linear movement to the load stage in a second direction that is substantially orthogonal to the first direction.

[0113] Example 13: The device according to Example 12, wherein the magnet assembly has a width in a direction that is substantially orthogonal to the first direction sufficient to allow movement of the load stage in a direction that is substantially orthogonal to the first direction.

[0114] Example 14: The device according to any one of Example 12 or Example 13, wherein the magnet assembly is wide enough to accommodate the expected amount of movement in the second direction.

[0115] Example 15: The device according to Example 14, wherein the width of the magnet assembly is selected such that the coil bearing plate remains substantially within the magnetic field generated by the magnet assembly.

[0116] Example 16: The device according to any one of the foregoing Example 12 and subsequent embodiments, wherein the at least one second actuator coupled to the load stage is further configured to provide rotational movement to the load stage.

[0117] Example 17: One embodiment of the disclosed subject matter describes a device for providing motion along at least two linear axes, each of the at least two linear axes being substantially orthogonal to each other. The device includes a first linear motor for providing linear motion in a first direction. The first linear motor includes a magnet assembly and a coil bearing plate. The coil bearing plate is substantially surrounded by the magnet assembly on at least two sides. The coil bearing plate is arranged to move in at least the first direction via a magnetic field generated within the first linear motor.

[0118] Example 18: The device according to Example 17, wherein the linear motion in the second direction does not require a second linear motor mounted to the first linear motor.

[0119] Example 19: The device according to any one of the preceding Example 17 and subsequent examples, wherein the magnet assembly has a width in a direction substantially orthogonal to the first direction sufficient to permit movement of the load stage in a direction substantially orthogonal to the first direction.

[0120] Example 20: The device according to any one of the preceding Example 17 and subsequent examples, wherein the at least one second actuator coupled to the load stage is further configured to provide rotational motion to the load stage.

[0121] Example 21: One embodiment of the disclosed subject matter describes a device for providing motion to a load stage in a first direction while permitting motion of the load stage in second and third directions. The device includes: a shaft for applying torque to the load stage; one or more z-direction load stage actuators mechanically coupled to the shaft to adjust the height of the load stage above a substrate. A motion actuator is mechanically coupled to the shaft and positioned adjacent to the one or more z-direction load stage actuators to apply a force to the shaft.

[0122] Example 22: The device according to Example 21, the device further including a bell crank assembly coupled between the motion actuator and the shaft. The bell crank assembly is configured to provide a force to the shaft to apply the torque to the one or more z-direction load stage actuators.

[0123] Example 23: The device according to Example 22, wherein the torque applied to the one or more z-direction load stage actuators is for providing a substantially uniform force to the load stage in the z-direction and substantially preventing any θ rotation of the load stage.

[0124] Example 24: The apparatus according to any one of the preceding embodiments, wherein the motion actuator is configured to apply the force on the shaft in a direction substantially transverse to the direction of the force applied to the load stage by the one or more z-direction load stage actuators.

[0125] Example 25: The apparatus according to any one of the preceding embodiments, the apparatus further comprising an encoder to determine a linear distance difference in the first direction based on a circular-to-linear conversion.

[0126] Example 26: The apparatus according to any one of the preceding embodiments, wherein each of the first direction, the second direction, and the third direction is substantially orthogonal to each other.

[0127] Example 27: The apparatus according to any one of the preceding embodiments, wherein the one or more z-direction load stage actuators are electrically connected to an electrical signal line to control the height of the load stage above the substrate in the first direction.

[0128] Example 28: The apparatus according to any one of the preceding embodiments, the apparatus further comprising a first set of air bearings and a second set of air bearings, the first set of air bearings and the second set of air bearings being coupled to the load stage to maintain a fixed distance relationship between the rear side of the load stage and the transfer bridge on which the load stage is positioned.

[0129] Example 29: The apparatus according to any one of the preceding embodiments, the apparatus further comprising at least one rear bearing, the at least one rear bearing being mounted on a portion of the load stage that is opposite to the portion on which the component will be mounted to the load stage.

[0130] Example 30: The apparatus according to any one of the preceding embodiments, the apparatus further comprising a vacuum air bearing, the vacuum air bearing being mounted on a portion of the load stage that is opposite to the portion on which the component will be mounted to the load stage.

[0131] Example 31: One embodiment of the disclosed subject matter describes an apparatus configured to provide motion to a load stage in a first direction while allowing motion of the load stage in second and third directions, each of the directions being substantially orthogonal to each other. The apparatus includes: a shaft configured to apply torque to the load stage; at least a pair of z-direction load stage actuators mechanically coupled to each other and mounted on opposite ends of the shaft, the at least a pair of z-direction load stage actuators configured to adjust the height of the load stage above a substrate; and a motion actuator located between the at least a pair of z-direction load stage actuators. The motion actuator is configured to apply a force on the shaft in a direction substantially transverse to the direction of the force applied to the load stage by the at least a pair of z-direction load stage actuators. A bell crank assembly is coupled between the motion actuator and the shaft. The bell crank assembly is configured to provide the force to the shaft to apply the torque to the at least a pair of z-direction load stage actuators.

[0132] Example 32: The apparatus according to Example 31, wherein the torque applied to the at least a pair of z-direction load stage actuators is configured to provide a substantially uniform force to the load stage in the z-direction and substantially prevent any θ rotation of the load stage.

[0133] Example 33: The apparatus according to any one of Example 31 or Example 32, wherein the motion actuator is configured to apply the force on the shaft in a direction substantially transverse to the direction of the force applied to the load stage by the at least a pair of z-direction load stage actuators.

[0134] Example 34: The apparatus according to any one of Example 31 to Example 33, wherein the at least a pair of z-direction load stage actuators are electrically coupled to electrical signal lines to control the height of the load stage above the substrate in the first direction.

Claims

1. A device for providing motion on at least two linear axes, each of the at least two linear axes being substantially orthogonal to each other, the device comprising: A load stage; A first actuator coupled to the load stage and configured to provide linear motion to the load stage in a first direction; A wide magnet group coupled within the first actuator, the wide magnet group having a width sufficient to allow movement of the load stage in a direction substantially orthogonal to the first direction; And At least one second actuator coupled to the load stage and configured to provide at least one of linear motion and rotational motion to the load stage in a second direction substantially orthogonal to the first direction.

2. The device according to claim 1, further comprising at least one third actuator proximate to and coupled to an edge of the load stage and configured to apply a force transverse to the edge to which the third actuator is coupled, the force providing rotational motion to the load stage.

3. The device according to claim 1, further comprising at least one rear preload bearing mounted on a portion of the load stage opposite to another portion on which a component will be mounted to the load stage.

4. The device according to claim 1, further comprising at least one bottom preload bearing mounted on a lower portion of the load stage.

5. The device according to claim 4, wherein Each of the at least one rear preload bearing and the at least one bottom preload bearing includes an air bearing.

6. The device according to claim 1, further comprising a vacuum air bearing mounted on a portion of the load stage opposite to another portion on which a component will be mounted to the load stage.

7. The device according to claim 1, further comprising at least one position encoding system to indicate the distance of the linear motion of the load stage in at least the first direction.

8. The apparatus according to claim 1, wherein, The first actuator includes a linear motor.

9. The apparatus according to claim 1, wherein, The at least one second actuator includes a voice coil motor.

10. The device according to claim 1, wherein, The at least one second actuator includes a linear motor.

11. The device according to claim 1, further comprising at least a first group of air bearings coupled to the load stage.

12. A device for providing motion on at least two linear axes, each of the at least two linear axes being substantially orthogonal to each other, the device comprising: A load stage having a mounting plate; A first linear motor configured to provide linear motion to the load stage in a first direction, the first linear motor including a magnet group and a coil bearing plate coupled to the mounting plate of the load stage and substantially surrounded by the magnet group on at least two sides, the coil bearing plate being arranged to move the load stage in at least the first direction via a magnetic field generated within the first linear motor; And At least one second actuator, the at least one second actuator being coupled to the load stage, the at least one second actuator being configured to provide at least linear motion to the load stage in a second direction that is substantially orthogonal to the first direction.

13. The apparatus according to claim 12, wherein, The magnet assembly has a width in a direction that is substantially orthogonal to the first direction that is sufficient to permit movement of the load stage in a direction that is substantially orthogonal to the first direction.

14. The apparatus according to claim 12, wherein, The magnet assembly is wide enough to accommodate an expected amount of movement in the second direction.

15. The device according to claim 14, wherein, The width of the magnet assembly is selected such that the coil bearing plate remains substantially within the magnetic field generated by the magnet assembly.

16. The apparatus according to claim 12, wherein, The at least one second actuator coupled to the load stage is further configured to provide rotational motion to the load stage.

17. An apparatus for providing motion along at least two linear axes, each of the at least two linear axes being substantially orthogonal to one another, the apparatus comprising: A first linear motor configured to provide linear motion in a first direction, the first linear motor including a magnet assembly and a coil bearing plate, the coil bearing plate being substantially surrounded by the magnet assembly on at least two sides, the coil bearing plate being arranged to move in at least the first direction via a magnetic field generated within the first linear motor.

18. The apparatus according to claim 17, wherein, The linear motion in the second direction does not require a second linear motor mounted to the first linear motor.

19. The device according to claim 17, wherein, The magnet assembly has a width in a direction that is substantially orthogonal to the first direction that is sufficient to permit movement of a load stage in a direction that is substantially orthogonal to the first direction.

20. The device according to claim 17, wherein At least one second actuator coupled to a load stage is further configured to provide rotational motion to the load stage.

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