A compact multi-axis precision motion stage

Abstract

The present invention discloses a compact multi-axis precision motion stage; it comprises, from bottom to top, a primary stage, a secondary stage, and a tertiary stage. The primary stage is an x-axis linear motion stage, the secondary stage is an Rx rotary motion stage, and the tertiary stage comprises a Y and Z linear motion stage and an Rz rotary motion stage. The motion stage of the present invention features a compact structure, a large motion range, a small footprint, and strong installation adaptability. The arrangement of suitable actuators as drivers enables high motion accuracy and robustness on each axis, while also offering low power consumption, non-magnetic properties, low heat generation, and high reliability.

Description

Technical Field

[0001] The present invention relates to the technical field of precision motion stages, and in particular to a compact multi-axis precision motion stage. Background Art

[0002] As optical inspection equipment becomes more integrated and its size continues to shrink, higher requirements are placed on inspection technology and accuracy. Focused ion beam inspection (FIB) / electron beam inspection (EBI) are being valued by the new generation of optical inspection devices due to their advantages of fast inspection speed and high detection sensitivity. In high-precision positioning systems for optical inspection equipment, the motion stage travel is typically on the order of tens of millimeters, while the accuracy reaches the nanometer and sub-nanometer levels. However, these systems are limited by factors such as the working vacuum space, operating power consumption, operating stability, and lightweight structure. This places new demands on the structural layout and actuation methods of multi-axis motion stages.

[0003] Optical inspection equipment often includes a multi-axis motion stage to adjust the inspection stage's accuracy, dynamic compensation, and leveling, focusing, and exposure. Maximizing the use of the workspace to achieve large-stroke motion while balancing the stage's operating conditions and control accuracy makes it crucial to design a compact, space-efficient multi-axis precision motion stage. Summary of the Invention

[0004] In order to solve the design requirements of multi-axis precision motion stage with limited space and large motion range, the purpose of the present invention is to provide a compact multi-axis precision motion stage used in dual-beam detection equipment, which can realize X-axis, Y-axis, Z-axis linear motion, and R X Axis, R Z Axis rotational motion. The motion platform of the present invention has the characteristics of compact structure, large motion range, small volume, and strong installation adaptability. It uses piezoelectric actuators as driving modules to achieve high motion accuracy and high robustness on each motion axis, while also having low power consumption, non-magnetic low heat and high reliability.

[0005] The technical solution of the present invention is specifically described as follows.

[0006] A compact multi-axis precision motion table, comprising a first-stage motion table, a second-stage motion table and a third-stage motion table, and also comprising a bottom frame, a middle frame, a rotation frame and a top frame;

[0007] The first-level motion platform includes two X-axis linear guides, an X-axis linear drive module, and an X-axis ceramic block. The X-axis linear guides are cross-roller guides. The two guides in each set of cross-roller guides are fixedly connected to the middle frame and the bottom frame respectively. The two guides are connected by cross rollers to achieve a sliding connection between the middle frame and the bottom frame. The X-axis ceramic block is fixedly mounted on the bottom of the middle frame, and the X-axis linear drive module is fixedly mounted on the bottom frame. The contact friction between the X-axis linear drive module and the X-axis ceramic block enables the middle frame to move relative to the bottom frame in the X direction.

[0008] The secondary motion platform includes a rotating bracket, two rotating supports, an Rx-direction rotation drive module, two inner arc guide rails, two outer arc guide rails and a rotating ceramic block; the rotating bracket is fixedly connected to the middle frame, the two inner arc guide rails are fixedly installed on the rotating bracket, the rotating ceramic block is fixedly connected to the rotating frame, and two outer arc guide rails are installed on the rotating ceramic block. The two inner arc guide rails and the two outer arc guide rails are installed through cross rollers to form two sets of cross roller guide rails, so that a sliding connection is formed between the inner arc guide rails and the outer arc guide rails; the rotating supports are installed on both sides of the middle frame, and the Rx-direction rotation drive modules are respectively installed on the rotating supports, and the Rx-direction rotation drive modules are respectively in contact and friction with the rotating ceramic blocks to realize the arc rotation of the rotating frame relative to the middle frame in the Rx direction;

[0009] The three-stage motion table includes a first Y-direction linear inner guide rail, a second Y-direction linear inner guide rail, a Y-direction linear drive module, a Y-direction ceramic block, a Z-direction linear guide rail, a Z-direction motion slider, a Z-direction linear drive module, a Z-direction ceramic block, a spring traction mechanism and an Rz-direction rotation drive module;

[0010] The Y-direction linear inner guide and the Y-direction ceramic block are mounted on the rotating frame, and the Y-direction linear inner guide and the Y-direction linear drive module are mounted on the top frame. The Y-direction linear inner guide and the Y-direction linear inner guide are connected by cross rollers to form two sets of cross roller guides, thereby forming a sliding connection between the rotating frame and the top frame. The Y-direction linear drive module and the Y-direction ceramic block achieve contact friction to realize the movement of the top frame relative to the rotating frame in the Y direction.

[0011] The Z-direction linear guide and the Z-direction linear drive module are installed on the top frame; the Z-direction linear guide is installed with a Z-direction motion slider, and the Z-direction ceramic block and the Rz-direction rotation drive module are installed on the Z-direction motion slider. The Z-direction linear drive module and the Z-direction ceramic block realize the movement of the Z-direction motion slider relative to the top frame in the Z direction through contact friction. The spring traction mechanism is connected to the Z-direction motion slider. The output direction of the spring traction mechanism is parallel to the movement direction of the Z-direction motion slider to prevent the Z-direction motion slider from swaying or getting stuck. The Rz-direction rotation drive module is an Rz-direction rotation motor.

[0012] In the present invention, the inner arc guide rail is composed of two sections of small arc guide rails.

[0013] In the present invention, the spring traction mechanism includes a clockwork spring, a clockwork spring bracket and a spring clamp. One end of the clockwork spring is fixed to the clockwork spring bracket, and the other end is fixed to the spring clamp at the bottom of the top frame. The spring clamp is connected to the Z-direction motion slider.

[0014] In the present invention, a Z-direction limiting block is also arranged on the top frame.

[0015] In the present invention, the X-direction linear drive module, the Rz-direction rotational drive module, the Y-direction linear drive module, the Z-direction linear drive module and the Rz-direction rotational drive module adopt piezoelectric actuators.

[0016] In the present invention, a grating ruler is further provided for detecting the linear displacement or angular displacement respectively generated in the linear motion and rotational motion of the first-stage motion stage, the second-stage motion stage, and the third-stage motion stage.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] The multi-axis motion platform structure of the present invention fully utilizes the working space while meeting the requirements of large-stroke motion, while taking into account the lightweight design requirements and working power consumption requirements. The structure is compact, has high motion accuracy and stability, and has good economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic structural diagram of a compact multi-axis precision motion table of the present invention.

[0020] Figure 2 This is a schematic structural diagram of a first-stage motion stage of a compact multi-axis precision motion stage of the present invention.

[0021] Figure 3 This is a Z-direction view of the first-level motion stage structure of a compact multi-axis precision motion stage of the present invention.

[0022] Figure 4 This is a schematic structural diagram of a secondary motion stage of a compact multi-axis precision motion stage of the present invention.

[0023] Figure 5 This is a schematic diagram of the structure of a three-stage compact multi-axis precision motion platform of the present invention.

[0024] Figure 6 This is a schematic diagram of the combined structure of a compact multi-axis precision motion platform and a two-stage and three-stage motion platform of the present invention.

[0025] Numbers in the figure: 1-first-level motion table, 2-second-level motion table, 3-third-level motion table, 4-rotating support, 11-bottom frame, 13-middle frame, 15-inner arc guide rail, 16-X-axis linear drive module, 22-rotating frame, 24-outer arc guide rail, 31-Y-axis linear drive module, 32-Z-axis linear drive module, 33-Rz-axis rotation drive module, 34-top frame, 35-Z-axis linear guide rail, 36-Z-axis motion slider, 37-spring traction mechanism, 111-X-axis guide rail top screw, 112-X-axis grating ruler, 121, 122-X-axis linear guide rail, 131-rotating support positioning hole, 141, 142-rotating bracket, 1411-rotating grating positioning hole, 151, 152-small arc guide rail, 211, 212-Rz-axis rotation Rotating drive module, 221-rotating frame positioning hole, 222-Y-axis ceramic block, 223-Y-axis grating scale steel strip, 231, 232-rotating ceramic block, 2311-rotating ceramic block top screw, 2312-external arc guide rail positioning hole, 251, 252-first Y-axis linear inner guide rail, 341-Z-axis grating scale fixing block, 342-Z-axis linear guide rail fixing block, 343-Z-axis linear drive module fixing block, 344-Y-axis linear drive module fixing block, 345-Z-axis limit block, 361-Rz-axis rotation drive module fixing block, 362-spring clamp, 363-Z-axis grating scale, 371-spring spring, 372-spring spring bracket, 381-Y-axis grating scale, 382-Y-axis grating scale fixing block, 391, 392-second Y-axis linear inner guide rail. DETAILED DESCRIPTION

[0026] It should be noted that the embodiments and features of the embodiments in this application may be combined with each other unless they conflict. To meet the design requirements of the working environment of the ultra-precision vacuum motion stage, the present invention uses a piezoelectric actuator as an example of a drive module. The technical solution of the present invention will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments.

[0027] The present invention provides a compact multi-axis precision motion stage, comprising a primary motion stage 1, a secondary motion stage 2, and a tertiary motion stage 3, and also comprising a bottom frame 11, a middle frame 13, a rotating frame 22, and a top frame 34. The primary motion stage 1 is an X-axis linear motion stage, the secondary motion stage 2 is an Rx rotary motion stage that rotates around the X-axis, and the tertiary motion stage 3 is a Y and Z linear motion stage and an Rz rotary motion stage that rotates around the Z-axis.

[0028] The first-level motion platform 1 includes two X-axis linear guides 121 and 122, an X-axis linear drive module 16, an X-axis ceramic block 17, and an X-axis grating scale 112. The X-axis linear guides 121 and 122 are cross-roller guides. The two guides in each set of cross-roller guides are fixed to the middle frame 13 and the bottom frame 11 by screws, and the two guides are connected by cross rollers to achieve a sliding connection between the middle frame 13 and the bottom frame 11. The X-axis ceramic block 17 is fixedly mounted on the bottom of the middle frame 13, and the X-axis linear drive module 16 is fixedly mounted on the bottom frame 11. The X-axis linear drive module 16 contacts the X-axis ceramic block 17, and realizes the movement of the middle frame 13 in the X-axis through contact friction, generating X-axis displacement. An X-axis guide rail top screw 111 is also provided on the bottom frame 11, and the X-axis guide rail top screw 111 contacts the X-axis linear guide 122 to provide an inward pre-tightening force. The X-axis grating scale 112 is fixed on the bottom frame 11, and cooperates with the X-axis grating scale steel belt provided at the bottom of the middle frame 13 to measure the size of the X-axis linear displacement that occurs when the X-axis linear drive module 16 drives the middle frame 13 to move relative to the bottom frame 11.

[0029] The secondary motion platform 2 includes rotating brackets 141, 142, two rotating supports 4, Rx-direction rotating drive modules 211, 212, two inner arc guide rails 15, two outer arc guide rails 24, and rotating ceramic blocks 231, 232; the rotating brackets 141, 142 are fixedly connected to the middle frame 13 by screws, and the rotating ceramic blocks 231, 232 are connected to the rotating frame 22 through the rotating frame positioning holes 221; the rotating brackets 141, 142 are fixedly installed on the middle frame 13, and the rotating ceramic blocks 231, 232 are fixedly connected to the rotating frame 22 through the rotating frame positioning holes 221; Install two inner arc guide rails 15, and install two outer arc guide rails 24 on the rotating ceramic blocks 231 and 232 through the outer arc guide rail positioning holes 2312 by screws. The two inner arc guide rails 15 and the two outer arc guide rails 24 are installed through cross rollers to form two sets of cross roller guide rails. A sliding connection is formed between the inner arc guide rails 15 and the outer arc guide rails 24 for Rx rotation guidance. In order to meet the motion stroke, the inner arc guide rail 15 can be composed of two small arc guide rails 151 and 152. 152 is connected; a rotating ceramic block top screw 2311 is also provided on the rotating ceramic block 231, and a pre-tightening force is provided to the outer arc guide rail 24 and the inner arc guide rail 15 through the rotating ceramic block top screw 2311; the rotating bracket 141 is installed with the Rx-direction grating ruler through the rotating grating positioning hole 1411; the rotating support 4 is installed on both sides of the middle frame 13 through the rotating support positioning hole 131, and the Rx-direction rotation drive modules 211 and 212 are respectively installed on the rotating support 4, and the Rx-direction rotation drive modules 211 and 212 are in contact with the rotating ceramic blocks 231 and 232 respectively. The Rx-direction rotation drive modules 211 and 212 are in contact and friction with the rotating ceramic blocks 231 and 232, so that the rotating frame 22 rotates in an arc shape relative to the middle frame 13 in the Rx direction, generating angular displacement; the measurement of the Rx-direction angular displacement is achieved by the cooperation between the Rx-direction grating ruler installed on the rotating bracket 141 and the Rx-direction grating ruler steel belt installed on the rotating ceramic block.

[0030] The three-stage motion platform 3 includes two first Y-axis linear inner guide rails 251 and 252, two second Y-axis linear inner guide rails 391 and 392, a Y-axis linear drive module 31, a Y-axis ceramic block 222, a Y-axis grating scale 381, a Y-axis grating scale steel belt 223, a Z-axis linear guide rail 35, a Z-axis motion slider 36, a Z-axis linear drive module 32, a Z-axis ceramic block, a spring traction mechanism 37, a Z-axis grating scale 363 and an Rz-axis rotation drive module 33.

[0031] Two Y-direction linear inner guide rails 251, 252, Y-direction ceramic block 222 and Y-direction grating steel belt 223 are installed on the rotating frame 22, and two Y-direction linear inner guide rails 391, 392, Y-direction linear drive module 31 and Y-direction grating steel belt 381 are installed on the top frame 34; the two Y-direction linear inner guide rails 251, 252 and the two Y-direction linear inner guide rails 391, 392 are connected by cross rollers to form two sets of cross roller guide rails to realize the connection between the rotating frame 22 and the top frame 34. The Y-axis linear drive module 31 is fixed to the top frame 34 through the Y-axis linear drive module fixing block 344. The Y-axis linear drive module 31 contacts and rubs with the Y-axis ceramic block 222, causing the top frame 34 to move in the Y-axis relative to the rotating frame 22, thereby generating a Y-axis displacement. The size of the Y-axis linear displacement can be measured by the Y-axis grating scale 381 fixed to one side of the top frame 34 by the Y-axis grating scale fixing block 382 and the Y-axis grating scale steel belt 223 on the rotating frame 22.

[0032] The Z-axis linear guide 35, the Z-axis linear drive module 32, and the Z-axis grating ruler 363 are respectively mounted on the top frame 34 through the Z-axis linear guide fixed block 342, the Z-axis linear drive module fixed block 343, and the Z-axis grating ruler fixed block 341; a Z-axis motion slider 36 is mounted on the Z-axis linear guide 35, and a Z-axis ceramic block is mounted on the Z-axis motion slider 36. The contact friction between the Z-axis linear drive module 32 and the Z-axis ceramic block causes the Z-axis motion slider 36 to move in the Z direction relative to the top frame 34; the spring traction mechanism 37 includes a spring spring 371, a spring spring bracket 372, and a spring clamp 362. One end of the spring spring 371 is fixed to a spring bracket 372 provided on the top frame 34. The clockwork spring bracket 372 on the lower frame 34 has its other end fixed to the spring clamp 362 at the bottom of the top frame 34. The spring clamp 362 is connected to the Z-direction motion slider 36. The output direction of the spring traction mechanism 37 is parallel to the motion direction of the Z-direction motion slider 36 to prevent the Z-direction motion slider 36 from swinging or getting stuck. A Z-direction limit block 345 is also arranged above the top frame 34 to limit the Z-direction motion limit position of the Z-direction motion slider 36. The linear displacement of the Z-direction motion slider 36 relative to the top frame 34 is measured by the Z-direction grating scale 363 installed on the top frame and the Z-direction grating scale steel belt installed on the Z-direction motion slider 36.

[0033] The Rz-direction rotation drive module 33 is installed on the Z-direction motion slider 36 through the Rz-direction rotation drive module fixing block 361. The Rz-direction rotation drive module 33 is an independent rotation module, which generates angular displacement through its own Rz-direction rotation movement. The angular displacement is measured by the Rz-direction grating ruler arranged inside the Rz-direction rotation drive module.

[0034] It should be noted that the terms used here are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. Unless otherwise specifically stated, the relative arrangement of the components and steps, numerical expressions and numerical values described in these embodiments do not limit the scope of this application. At the same time, it should be understood that for ease of description, the dimensions of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The techniques, methods and equipment known to ordinary technicians in the relevant fields may not be discussed in detail, but where appropriate, the techniques, methods and equipment should be considered as part of the authorized specification. In all examples shown and discussed here, any specific values should be interpreted as merely exemplary and not as limitations.

[0035] For ease of description, spatially relative terms such as "on," "above," "on the upper surface of," "upper," and X-axis, Y-axis, and Rx, etc., may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures.

[0036] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of this application.

[0037] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A compact multi-axis precision motion stage, characterized in that: It includes a first-level motion platform (1), a second-level motion platform (2) and a third-level motion platform (3), and also includes a bottom frame (11), a middle frame (13), a rotating frame (22) and a top frame (34); The first-level motion platform (1) includes two X-direction linear guide rails (121) and (122), an X-direction linear drive module (16) and an X-direction ceramic block (17); the X-direction linear guide rails (121) and (122) are cross roller guide rails, and the two guide rails in each set of cross roller guide rails are fixedly connected to the middle frame (13) and the bottom frame (11) respectively, and the two guide rails are connected by cross rollers to realize the sliding connection between the middle frame (13) and the bottom frame (11); the X-direction ceramic block (17) is fixedly installed at the bottom of the middle frame (13), and the X-direction linear drive module (16) is fixedly installed on the bottom frame (11); the X-direction linear drive module (16) and the X-direction ceramic block (17) realize the movement of the middle frame (13) relative to the bottom frame (11) in the X direction through contact friction between the X-direction linear drive module (16) and the X-direction ceramic block (17); The secondary motion platform (2) includes rotating brackets (141), (142), two rotating supports (4), Rx-direction rotating drive blocks (211), (212), two inner arc guide rails (15), two outer arc guide rails (24) and rotating ceramic blocks (231), (232); the rotating brackets (141), (142) are fixedly connected to the middle frame (13), and the two inner arc guide rails (15), the rotating ceramic blocks (231), (232) and The rotating frame (22) is fixedly connected, and two outer arc guide rails (24) are installed on the rotating ceramic blocks (231) and (232). The two inner arc guide rails (15) and the two outer arc guide rails (24) are installed through cross rollers to form two sets of cross roller guide rails, so that a sliding connection is formed between the inner arc guide rails (15) and the outer arc guide rails (24); the rotating support (4) is installed on both sides of the middle frame (13), and the Rx direction rotation drive modules (211) and (212) are respectively installed on the rotating support (4). x The rotation drive modules (211) and (212) respectively contact and rub against the rotating ceramic blocks (231) and (232) to achieve arc-shaped rotation of the rotating frame (22) relative to the middle frame (13) in the Rx direction; The three-stage motion platform (3) includes a first Y-direction linear inner guide rail (251), (252), a second Y-direction linear inner guide rail (391), (392), a Y-direction linear drive module (31), a Y-direction ceramic block (222), a Z-direction linear guide rail (35), a Z-direction motion slider (36), a Z-direction linear drive module (32), a Z-direction ceramic block, a spring traction mechanism (37) and an Rz-direction rotation drive module (33); The Y-direction linear inner guide rails (251), (252) and the Y-direction ceramic block (222) are mounted on the rotating frame (22), and the Y-direction linear inner guide rails (391), (392) and the Y-direction linear drive module (31) are mounted on the top frame (34); the Y-direction linear inner guide rails (251), (252) and the Y-direction linear inner guide rails (391), (392) are connected by cross rollers to form two sets of cross roller guide rails, so that a sliding connection is formed between the rotating frame (22) and the top frame (34), and the Y-direction linear drive module (31) and the Y-direction ceramic block (222) realize the movement of the top frame (34) relative to the rotating frame (22) in the Y direction through contact friction; The Z-direction linear guide rail (35) and the Z-direction linear drive module (32) are mounted on the top frame (34); a Z-direction motion slider (36) is mounted on the Z-direction linear guide rail (35); a Z-direction ceramic block and an Rz-direction rotation drive module (33) are mounted on the Z-direction motion slider (36); the Z-direction linear drive module (32) and the Z-direction ceramic block realize the movement of the Z-direction motion slider (36) relative to the top frame (34) in the Z direction through contact friction; a spring traction mechanism (37) is connected to the Z-direction motion slider (36); the output direction of the spring traction mechanism (37) is parallel to the movement direction of the Z-direction motion slider (36) to prevent the Z-direction motion slider (36) from deflecting or getting stuck; the Rz-direction rotation drive module (33) is an Rz-direction rotation motor; wherein: The inner arc guide rail (15) is composed of two sections of small arc guide rails (151) (152); a Z-direction limit block (345) is also arranged on the top frame (34).

2. The compact multi-axis precision motion stage according to claim 1, characterized in that: The spring traction mechanism (37) includes a spring (371), a spring bracket (372) and a spring clamp (362). One end of the spring (371) is fixed to the spring bracket (372), and the other end is fixed to the spring clamp (362) at the bottom of the top frame 34. The spring clamp (362) is connected to the Z-direction motion slider (36).

3. The compact multi-axis precision motion stage according to claim 1, characterized in that: The X-direction linear drive module (16), the Rz-direction rotational drive module (211) (212), the Y-direction linear drive module (31), the Z-direction linear drive module (32) and the Rz-direction rotational drive module (33) use piezoelectric actuators.

4. The compact multi-axis precision motion stage according to claim 1, characterized in that: A grating ruler is also provided for detecting the linear displacement or angular displacement respectively generated in the linear motion and rotational motion of the first-stage motion platform (1), the second-stage motion platform (2), and the third-stage motion platform (3).

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