Wafer rotation positioning carrying platform

Abstract

The invention provides a wafer rotation positioning platform deck, and belongs to the semiconductor driving technology, the wafer rotation positioning platform deck comprises a supporting module, a rotation driving module and a plurality of gravity balance modules arranged on the bottom surface of a supporting disc, the rotation driving module drives the supporting module to rotate around the axis, and positioning control of the rotation angle is achieved through air flotation and magnetic attraction; the wafer rotating and positioning platform deck is accurate and controllable in rotation, air flotation magnetic force position locking and gravity balance are adopted, driving and control are more precise, and the wafer rotating and positioning platform deck is convenient to popularize and apply in the fields of semiconductor overlay alignment, quantity detection, manufacturing and high-end precise instrument driving.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of semiconductor driving, and particularly relates to a wafer rotating positioning platform. BACKGROUND

[0002] In a semiconductor wafer detection and processing device, a wafer is generally carried and positioned by a platform, however, the existing platform generally needs to rotate around the Z axis, but the inertia of movement will affect the driving precision of the platform, and thus the subsequent process flow is inevitably affected. Therefore, in order to improve the rotation or angle adjustment precision of wafer carrying, a wafer platform capable of accurately controlling the rotation timing is needed to adapt to the wafer high-precision positioning carrying in the scenarios of overlay, defect, CD (critical dimension) measurement and processing. SUMMARY

[0003] In order to overcome the shortcomings of the prior art, the purpose of the present application is to provide a wafer rotating positioning platform which can solve the above problems.

[0004] A wafer rotating positioning platform comprises a support module and a rotating drive module, the rotating drive module drives the support module to rotate around the axis, and the rotating angle is controlled by air floating and magnetic attraction.

[0005] Further, the support module comprises a support disc with a middle opening and an upper plate spring, the rotating drive module is arranged at the middle opening position of the support disc, and the rotating positioning is controlled by the clutching of the support disc and the upper plate spring.

[0006] Further, the rotating drive module comprises an air floating cylinder shaft assembly, two groups of arc voice coil motors, air floating heads and rotating positioning magnets; the air floating cylinder shaft assembly comprises an air floating guide shaft and an air floating cylinder, the air floating guide shaft is non-contact embedded in the air floating cavity of the air floating cylinder, the air floating guide shaft is connected to the support disc, and the top of the air floating cylinder is connected to the bottom surface of the upper plate spring; the two groups of arc voice coil motors are arranged between the air floating cylinder and the support disc, thereby driving the support disc to rotate relative to the axis of the air floating cylinder; a plurality of air floating heads and rotating positioning magnets are uniformly distributed on the outer periphery of the upper plate spring, and the clutching of the upper plate spring and the support disc is realized by switching on and off the air.

[0007] Further, the wafer rotating positioning platform further comprises a plurality of gravity balance modules arranged on the bottom surface of the support disc, the gravity balance module comprises a magnetic spring transition sleeve, a magnetic spring mover and a magnetic spring stator; the top of the magnetic spring transition sleeve is connected to the bottom surface of the support disc, the bottom of the magnetic spring mover is connected to the lower part of the magnetic spring transition sleeve, the lower part of the magnetic spring mover is non-contact embedded in the accommodating cavity of the magnetic spring stator, and the bottom of the magnetic spring stator is fixed to.

[0008] Further, the wafer rotating positioning stage further comprises a stage base, the stage base comprises a base body, a rotating module installation counterbore and a gravity balance module installation counterbore are arranged on the upper surface of the base body; the rotating module installation counterbore is used for accommodating the bottom of the rotating drive module, and the gravity balance module installation counterbore is used for accommodating the bottom of the gravity balance module.

[0009] Further, the wafer rotating positioning stage further comprises a wafer carrier disc arranged above the supporting module, the wafer carrier disc comprises a carrier disc body, a plurality of carrier disc adsorption lug tables are radially arranged on the outer periphery of the carrier disc body, wafer adsorption blocks are arranged on the carrier disc adsorption lug tables, and two wafer fork grooves are arranged on the upper surface of the carrier disc body.

[0010] Compared with the prior art, the wafer rotating positioning stage has the advantages that the wafer rotating positioning stage is precisely controllable in rotation, and the air floating magnetic position locking and the gravity balance are adopted, so that the driving control is more precise, and the wafer rotating positioning stage is convenient for popularization and application in the fields of semiconductor overlay alignment, measurement, manufacturing and high-end precision instrument driving. BRIEF DESCRIPTION OF DRAWINGS

[0011] Figure 1 FIG. 1 is a schematic diagram of a wafer rotating positioning stage according to the present application; Figure 2 FIG. 2 is a schematic diagram of a stage base; Figure 3 FIG. 3 is a schematic diagram of an example of a wafer rotating positioning stage; Figure 4 FIG. 4 is a sectional view of the wafer rotating positioning stage; Figure 3 FIG. 5 is an exploded view of the wafer rotating positioning stage; Figure 5 Figure 3 FIG. 6 is a schematic diagram of the installation of an arc-shaped voice coil motor; Figure 6 FIG. 7 is a schematic diagram of a wafer transfer device. Figure 7 FIG. 8 is a schematic diagram of a wafer transfer device.

[0012] In the drawings: 10, stage base; 11, base body; 12, rotating module installation counterbore; 13, gravity balance module installation counterbore; 20, supporting module; 21, supporting disc; 22, upper plate spring; 23, lower plate spring; 231, plate spring groove; 232, torsion absorption hole; 233, plate spring pressing block assembly; 30, lifting and leveling module; ​40, rotation drive module; 41, air float cylinder shaft assembly; 42, arc voice coil motor; 421, motor yoke; 422, motor magnetic steel; 423, motor coil; 424, coil holder; 43, air float head; 44, rotation positioning magnet; 411, air float guide shaft; 4111, guide shaft connecting lug; 412, air float cylinder; 4121, float cylinder lug; 45, air float fixed adapter top plate; 46, porous graphite air ring; 47, check ring pressing head; 48, rotation grating assembly; 49, rotation limiting assembly; 50, gravity balance module; 51, magnetic spring transition sleeve; 52, magnetic spring mover; 53, magnetic spring stator; 60, wafer loading disc; 61, loading disc body; 62, loading disc adsorption lug platform; 63, wafer adsorption block; 64, wafer fork groove; 100, shock absorbing rack; 200, Y-axis first drive module; 300, Y-axis second drive module; 400, X-axis drive module; 500, wafer adsorption platform. DETAILED DESCRIPTION

[0013] To make the objectives, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some but not all of the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0014] A wafer rotation positioning platform, referring to Figures 1-6 , comprises a support module 20 and a rotation drive module 40. The rotation drive module 40 drives the support module 20 to rotate around an axis, and realizes positioning control of a rotation angle through air float magnetic adsorption.

[0015] The support module 20 comprises a support disc 21 with a middle opening and a leaf spring 22. The rotation drive module 40 is arranged at the middle opening position of the support disc 21, and controls rotation positioning through the clutching of the support disc 21 and the leaf spring 22. The leaf spring 22 is arc-shaped and has a closed end.

[0016] The rotation drive module 40 comprises an air float cylinder shaft assembly 41, two sets of arc voice coil motors 42, an air float head 43, and a rotation positioning magnet 44.

[0017] Specifically, the air floatation cylinder shaft assembly 41 comprises an air floatation guide shaft 411 and an air floatation cylinder 412, the air floatation guide shaft 411 is non-contactedly sleeved into the air floatation cavity of the air floatation cylinder 412, the air floatation guide shaft 411 is connected to the support disc 21, and the top of the air floatation cylinder 412 is connected to the bottom surface of the upper leaf spring 22.

[0018] The two sets of arc-shaped voice coil motors 42 are arranged between the air floatation cylinder 412 and the support disc 21, thereby driving the support disc 21 to rotate relative to the shaft center of the air floatation cylinder 412.

[0019] The multiple sets of air floatation heads 43 and the rotating positioning magnets 44 are uniformly distributed on the outer periphery of the upper leaf spring 22, and the air floatation heads 43 and the rotating positioning magnets 44 are in air blowing and breaking air connection with the support disc 21.

[0020] The top outer periphery of the air floatation guide shaft 411 extends outward to form guide shaft connecting lugs 4111 on opposite sides, the air floatation cylinder 412 is provided with limiting clamping grooves corresponding to the guide shaft connecting lugs 4111, and the guide shaft connecting lugs 4111 are connected to the support disc 21.

[0021] The air floatation head 43 is in a cylindrical shape, the rotating positioning magnet 44 in a cylindrical shape is arranged in the middle hollow part, and the rotating positioning magnet 44 is fixed to the air floatation head 43 by a magnet screw, so that the air floatation head 43 has an annular air blowing surface along the outer periphery of the rotating positioning magnet 44.

[0022] The two sets of arc-shaped voice coil motors 42 are oppositely arranged on the outer periphery of the air floatation cylinder 412, each set of arc-shaped voice coil motor 42 comprises a motor yoke 421, a motor magnetic steel 422, a motor coil 423 and a coil holder 424, the motor yoke 421 is mounted to the floatation lug 4121 arranged on the outer periphery of the air floatation cylinder 412, and the top of the coil holder 424 is connected to the support disc 21.

[0023] Further, the rotating drive module 40 further comprises an air floatation fixed adapter top plate 45, the bottom surface of the air floatation fixed adapter top plate 45 is fixedly connected to the top surface of the support disc 21 near the middle hole, the guide shaft connecting lugs 4111 of the air floatation guide shaft 411 are connected to the air floatation fixed adapter top plate 45, and the coil holders 424 of the two sets of arc-shaped voice coil motors 42 are also connected to the air floatation fixed adapter top plate 45.

[0024] Further, the rotating drive module 40 further comprises a porous graphite air ring 46, the columnar rotating positioning magnet 44 is sleeved into the lower recessed cavity of the air floatation head 43 through the center hole of the porous graphite air ring 46, and the top of the air floatation head 43 is screw-connected to the upper leaf spring 22 through a check ring pressing head 47.

[0025] The porous graphite air ring 46 blows air. The rotating positioning magnet 44 attracted to the upper leaf spring 22 can be separated.

[0026] Further, the rotary drive module 40 further comprises a gas-floating magnetic attraction bottom plate, the locking mounting hole of the support disc 21 is a through hole, the gas-floating magnetic attraction bottom plate is arranged below the support disc 21 and blocks the locking mounting hole, the bottom of the rotary positioning magnet 44 is magnetically attracted to the gas-floating magnetic attraction bottom plate and is controlled by the gas-floating head 43 to be in clutch or not.

[0027] In this example, the support disc 21 is a non-magnetic material, and therefore the gas-floating magnetic attraction bottom plate is provided with a ferromagnetic body. In this way, the weight of the support disc 21 and the entire platform can be reduced.

[0028] The wafer rotary positioning platform further comprises a plurality of gravity balance modules 50 arranged on the bottom surface of the support disc 21, the gravity balance module 50 comprises a magnetic spring transition sleeve 51, a magnetic spring mover 52 and a magnetic spring stator 53; the top of the magnetic spring transition sleeve 51 is connected to the bottom surface of the support disc 21, the bottom of the magnetic spring mover 52 is connected to the lower part of the magnetic spring transition sleeve 51, the lower part of the magnetic spring mover 52 is non-contact embedded into the accommodating cavity of the magnetic spring stator 53, and the bottom of the magnetic spring stator 53 is fixed.

[0029] In the case of setting the gas-floating fixed adapter top plate 45, the top of the magnetic spring transition sleeve 51 is connected to the gas-floating fixed adapter top plate 45, thereby indirectly connected to the support disc 21.

[0030] In the illustrated example, three sets of gravity balance modules 50 are arranged on the bottom surface of the support disc 21, and the gravity of the support disc 21 above is balanced by electromagnetic elastic force.

[0031] The wafer rotary positioning platform further comprises a platform base 10, as shown in Figure 2 The platform base 10 comprises a base body 11, a rotary module mounting counterbore 12 and a gravity balance module mounting counterbore 13 are opened on the upper surface of the base body 11; the rotary module mounting counterbore 12 is used to accommodate the bottom of the rotary drive module 40, and the gravity balance module mounting counterbore 13 is used to mount the bottom of the gravity balance module 50.

[0032] Specifically, the bottom of the gas-floating cylinder shaft assembly 41 is non-connected embedded in the rotary module mounting counterbore 12 on the top surface of the platform base 10, the bottom of the magnetic spring stator 53 is connected into the gravity balance module mounting counterbore 13 of the platform base 10, and the bottom of the magnetic spring stator 53 is connected into the gravity balance module mounting counterbore 13 of the platform base 10.

[0033] Further, the support module 20 further comprises a lower leaf spring 23, the lower leaf spring 23 is provided with a central hole and a leaf spring groove 231 is opened along the radial part to form an equal division of the spring plate area, the inner end of the leaf spring groove 231 is communicated with the leaf spring central hole, and the outer end of the leaf spring groove 231 is communicated with a torsion absorption hole 232; a plurality of spring plate areas are alternately connected to the upper surface of the support disc 21 and the upper surface of the middle part of the platform base 10 through a leaf spring pressing block assembly 233.

[0034] Further, the rotary drive module 40 further comprises a rotary grating assembly 48 and a rotary limiting assembly 49, the rotary grating assembly 48 is arranged on the support disc 21 outside one air floating head 43, and the rotary limiting assembly 49 is arranged on the support disc 21 outside the remaining air floating head 43.

[0035] Further, in order to make the wafer rotary positioning stage function diversified, meet multi-scene application, and increase the lifting and leveling function of the lifting and leveling module 30, the lifting and leveling module 30 comprises a lifting voice coil motor, a lifting grating ruler assembly, a lifting subdivision box and a lifting limiting assembly.

[0036] The bottom of the plurality of lifting voice coil motors is connected to the corresponding lifting module mounting counterbore of the stage base 10, and the top end of the lifting voice coil motor is connected to the support disc; the lifting grating ruler assembly is connected to the support disc 21 through a grating frame; the lifting grating ruler assembly is electrically connected to the lifting subdivision box; the lifting limiting assembly is connected to the stage base 10 and the support disc 21, and monitors the Z-direction position and limiting of the lifting voice coil motor through mechanical and photoelectric dual modes.

[0037] The lifting and leveling module 30 is provided with three groups, three lifting installation holes corresponding thereto are formed on the support disc 21, and the top end of the lifting voice coil motor and the top of the grating frame of the lifting grating ruler assembly are connected with the Z-axis installation top plate above through the lifting installation hole.

[0038] The lifting subdivision box is mounted on the stage base 10 through a box frame and is electrically connected with the lifting reading head of the lifting grating ruler assembly, so as to subdivide the lifting position and improve the detection precision.

[0039] The lifting limiting assembly comprises a mechanical limiting part and a photoelectric limiting part arranged on the outer periphery of the support disc 21.

[0040] Among them, referring to Figure 1 The wafer carrier disc 60 comprises a carrier disc body 61, a plurality of carrier disc adsorption lug tables 62 are arranged radially outside the outer periphery of the carrier disc body 61, wafer adsorption blocks 63 are arranged on the carrier disc adsorption lug tables 62, and two wafer cross grooves 64 are formed on the upper surface of the carrier disc body 61.

[0041] A wafer transfer device, referring to Figure 7, including the Y-axis first driving module 200 and the Y-axis second driving module 300 arranged on the damping rack 100, and the X-axis driving module 400 is connected and supported by the corresponding Y-axis driving module at both ends, and the wafer adsorption table 500 adopts the wafer rotating positioning table, and the wafer adsorption table 500 is arranged on the X-axis driving module 400; the Y-axis first driving module 200 and the Y-axis second driving module 300 are independently controlled and can be corrected in real time and regularly, so as to eliminate the residual error caused by the non-orthogonal relationship between the X-axis driving module 400 and the two Y-axis driving modules. The X-axis driving module 400 adopts a back-shaped structure of driving three sides of air floating, better providing the stability of guiding and the driving precision.

[0042] The Y-axis first driving module 200 and the Y-axis second driving module 300 are independently controlled and can be corrected in real time and regularly, so as to eliminate the residual error caused by the non-orthogonal relationship between the X-axis driving module 400 and the two Y-axis driving modules. The residual error correction principle is that the image acquisition module collects the linear image of the wafer on the wafer transfer device, the position processing module collects the position of the wafer transfer device in real time, the residual error correction calculation module compares and calculates the non-orthogonal residual error based on the actual wafer image collected by the image acquisition module and the standard wafer position image, and the main control analysis module controls the Y-axis first driving module 200 and the Y-axis second driving module 300 of the wafer transfer device to move longitudinally to realize the residual error correction.

[0043] The wafer adsorption table 500 is arranged on the X-axis sliding table plate of the X-axis driving module 400 and is integrated with the functions of lifting, rotating around the Z-axis and X-Y plane leveling.

[0044] The damping rack 100 and the longitudinal beam of the Y-axis driving module are made of marble or granite, which is stable and not easy to deform; the X-axis cross beam of the X-axis driving module 400 and the wafer disc 60 are made of silicon carbide, which is light and stable. The air floating assembly adopts an air floating pad.

[0045] The present scheme has been used in a wafer nanometer overlay detection system, an image and non-image wafer (including bright field and dark field) quantity detection system, and will be popularized to the processing scenes of photolithography, PCB and IC board in the future.

[0046] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, but not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A wafer rotation positioning stage, comprising a support module (20) and a rotation drive module (40), characterized in that: The rotation drive module (40) drives the support module (20) to rotate around the axis, and realizes the positioning control of the rotation angle through air-floating magnetic attraction.

2. The wafer rotation and positioning stage according to claim 1, wherein: The support module (20) comprises a support disk (21) with a central opening and an upper leaf spring (22). The rotation drive module (40) is arranged at the central opening of the support disk (21) and is rotationally positioned by clutch control of the upper leaf spring (22) and the support disk (21).

3. The wafer rotation and positioning stage according to claim 2, wherein: The rotary drive module (40) includes an air float shaft assembly (41), two sets of arc-shaped voice coil motors (42), an air float head (43) and a rotary positioning magnet (44); The air float cylinder shaft assembly (41) includes an air float guide shaft (411) and an air float cylinder (412), wherein the air float guide shaft (411) is non-contactly embedded in the air float cavity of the air float cylinder (412), the air float guide shaft (411) is connected to the support plate (21), and the top of the air float cylinder (412) is connected to the bottom surface of the upper leaf spring (22); Two sets of arc-shaped voice coil motors (42) are arranged between the air float (412) and the support plate (21), thereby driving the support plate (21) to rotate relative to the axis of the air float (412); A plurality of sets of air floating heads (43) and rotating positioning magnets (44) are evenly distributed on the periphery of the upper leaf spring (22), and the upper leaf spring (22) and the support disk (21) are connected and disconnected by air.

4. The wafer rotation and positioning stage according to claim 3, wherein: Two groups of arc-shaped voice coil motors (42) are arranged relative to each other on the periphery of the air float (412), and each group of arc-shaped voice coil motors (42) includes a motor iron yoke (421), a motor magnet (422), a motor coil (423) and a coil frame (424), and the motor iron yoke (421) is mounted on a float lug (4121) arranged on the periphery of the air float (412); the top of the coil frame (424) is connected to the support plate (21).

5. The wafer rotation and positioning stage according to claim 3, wherein: The rotary drive module (40) further includes a porous graphite air ring (46), a cylindrical rotary positioning magnet (44) passes through the center hole of the porous graphite air ring (46) and is inserted into the lower concave cavity of the air floating head (43), and the upper leaf spring (22) is screwed to the top of the air floating head (43) through a retaining ring pressure head (47).

6. The wafer rotation and positioning stage according to claim 2, wherein: The wafer rotation positioning platform also includes a plurality of gravity balance modules (50) arranged on the bottom surface of the support plate (21), and the gravity balance module (50) includes a magnetic spring transition sleeve (51), a magnetic spring mover (52) and a magnetic spring stator (53); the top of the magnetic spring transition sleeve (51) is connected to the bottom surface of the support plate (21), the bottom of the magnetic spring mover (52) is connected to the bottom of the magnetic spring transition sleeve (51), the bottom of the magnetic spring mover (52) is non-contactly embedded in the accommodating cavity of the magnetic spring stator (53), and the bottom of the magnetic spring stator (53) is fixed.

7. The wafer rotation and positioning stage according to claim 6, wherein: The wafer rotation positioning platform also includes a platform seat (10), and the platform seat (10) includes a platform body (11). A rotation module mounting countersunk hole (12) and a gravity balance module mounting countersunk hole (13) are provided on the upper surface of the platform body (11); the rotation module mounting countersunk hole (12) is used to accommodate the bottom of the rotation drive module (40), and the gravity balance module mounting countersunk hole (13) is used to install the bottom of the gravity balance module (50).

8. The wafer rotation and positioning stage according to claim 7, wherein: The support module (20) further includes a lower leaf spring (23), the lower leaf spring (23) has a central opening and a leaf spring groove (231) is formed along the radial portion to form an equally divided spring plate area, the inner end of the leaf spring groove (231) is connected to the leaf spring central hole, and the outer end of the leaf spring groove (231) is connected to a torsion absorption hole (232); the inner ends of the plurality of spring plate areas are alternately connected to the upper surface of the support disk (21) and the upper surface of the middle portion of the carrier seat (10) through the leaf spring pressure block assembly (233).

9. The wafer rotation and positioning stage according to claim 7, wherein: The rotary drive module (40) further comprises a rotary grating assembly (48) and a rotary limit assembly (49), wherein the rotary grating assembly (48) is arranged on a support disk (21) outside one air floating head (43), and the rotary limit assembly (49) is arranged on a support disk (21) outside the remaining air floating heads (43).

10. The wafer rotation and positioning stage according to claim 7, wherein: The wafer rotation positioning platform also includes a wafer carrier (60) arranged above the support module (20), the wafer carrier (60) includes a carrier body (61), a plurality of carrier adsorption lugs (62) are arranged radially outwardly on the outer periphery of the carrier body (61), a wafer suction block (63) is arranged on the carrier adsorption lug (62), and two wafer fork grooves (64) are opened on the upper surface of the carrier body (61).

Images