CN114114845A

CN114114845A - Substrate transfer unit and substrate transfer device

Info

Publication number: CN114114845A
Application number: CN202010899824.2A
Authority: CN
Inventors: 赵文波; 刘屈武
Original assignee: Shanghai Micro Electronics Equipment Co Ltd
Current assignee: Shanghai Micro Electronics Equipment Co Ltd
Priority date: 2020-08-31
Filing date: 2020-08-31
Publication date: 2022-03-01
Anticipated expiration: 2040-08-31
Also published as: CN114114845B

Abstract

The invention provides a substrate handover unit and a substrate handover device, wherein the substrate handover unit comprises a stator and a rotor; the stator comprises a coil and an inner cavity arranged along the axial direction, and the coil is circumferentially arranged around the inner cavity; the rotor comprises a magnet and an air bearing, and the magnet is movably arranged in the inner cavity along the axial direction of the stator; the magnet is used for moving along the axial direction of the stator under the driving of the coil; the magnet is connected in the inner cavity in an air floating mode through the air floating bearing; the air bearing at least comprises an upper air floating surface and a lower air floating surface, the upper air floating surface and the lower air floating surface are distributed at intervals along the axial direction of the stator, and the extending direction of the upper air floating surface is the same as that of the lower air floating surface. With the configuration, each substrate connection unit independently comprises the stator and the rotor, and can be independently adjusted, so that the integration difficulty is reduced. The stability and reliability of the substrate connection unit are further improved by the arrangement of the air bearing.

Description

Substrate transfer unit and substrate transfer device

Technical Field

The present invention relates to the field of semiconductor manufacturing technologies, and in particular, to a substrate transfer unit and a substrate transfer apparatus.

Background

The silicon wafer in the photoetching equipment is handed over by a special handing-over device to realize the functions of adsorption, linear transmission, release and the like of the silicon wafer, and the series of actions are required to be quickly completed in a short time and keep high reliability. With the improvement of the precision and the yield of the photoetching machine, the design of the connecting device is higher and higher, the traditional connecting device adopts an integrated connecting device of a voice coil motor and a mechanical guide rail, but in the prior art, a plurality of fixed heads of the integrated connecting device share one motor, the size is larger, and the integrated connecting device is not suitable for a narrow space. In addition, in the conventional interface device, the surface temperature or the internal coil temperature is too high, the mover part is easily interfered by an external magnetic field, and the like, and the control performance of the interface device, the service life of the voice coil motor, the interface precision and the integration efficiency are influenced by the problems.

Disclosure of Invention

The invention aims to provide a substrate transfer unit and a substrate transfer device, which are used for solving the problems that the transfer device in the prior art is large in size and is easily interfered by an external magnetic field.

To solve the above technical problem, the present invention provides a substrate transfer unit, comprising: a stator and a mover;

the stator comprises a coil and an inner cavity arranged along the axial direction, and the coil is circumferentially arranged around the inner cavity;

the rotor comprises a magnet and an air bearing, and the magnet is movably arranged in the inner cavity along the axial direction of the stator; the magnet is used for moving along the axial direction of the stator under the driving of the coil; the magnet is connected in the inner cavity in an air floating mode through the air floating bearing; the air bearing at least comprises an upper air floating surface and a lower air floating surface, the upper air floating surface and the lower air floating surface are distributed at intervals along the axial direction of the stator, and the extending direction of the upper air floating surface is the same as that of the lower air floating surface.

Optionally, the upper air bearing surface is annular, the lower air bearing surface includes more than two sub air bearing surfaces, and the more than two sub air bearing surfaces are arranged at an angle in the radial direction of the stator.

Optionally, the lower air bearing surface includes a plurality of sub air bearing surfaces, and the circle center of the inscribed circle of at least three sub air bearing surfaces is located on the axis of the upper air bearing surface.

Optionally, the rotor includes an air inlet, the air inlet is used for supplying air to the air bearing, and the air inlet is connected with the stator through a hose.

Optionally, the mover includes back iron, and the back iron is disposed at two ends of the magnet along an axial direction of the stator.

Optionally, the stator includes a ferromagnetic sleeve and a base, the ferromagnetic sleeve at least wraps the periphery of the coil, a cooling liquid channel is formed in the base, and at least part of the cooling liquid channel is overlapped with the coil along the axial direction of the stator; the ferromagnetic sleeve is in heat conduction connection with the base, and the coil is in heat conduction connection with the ferromagnetic sleeve.

Optionally, the mover includes a fixing head and an air suction port, the fixing head is used for adsorbing and supporting a substrate, the air suction port is communicated with the fixing head through an air suction pipeline and used for sucking air from the fixing head, and the air suction port is connected with the stator through a hose.

Optionally, the substrate interface unit further includes: the mechanical limiting assembly comprises two limiting parts which are arranged oppositely, the two limiting parts are arranged on the stator and the rotor respectively, and the mechanical limiting assembly is used for limiting the axial stroke of the rotor through the abutting of the two limiting parts.

Optionally, the substrate interface unit further includes: the grating scale assembly comprises a scale belt and a reading head which are oppositely arranged, the scale belt is arranged on the rotor, the reading head is arranged on the stator, and the grating scale assembly is used for measuring the axial displacement of the rotor relative to the stator.

In order to solve the above technical problem, the present invention further provides a substrate transfer apparatus, including: at least three substrate transfer units as described above, which are disposed in the same direction and configured to move in synchronization.

In summary, in the substrate cross-connecting unit and the substrate cross-connecting device provided by the invention, the substrate cross-connecting unit includes a stator and a mover; the stator comprises a coil and an inner cavity arranged along the axial direction, and the coil is circumferentially arranged around the inner cavity; the rotor comprises a magnet and an air bearing, and the magnet is movably arranged in the inner cavity along the axial direction of the stator; the magnet is used for moving along the axial direction of the stator under the driving of the coil; the magnet is connected in the inner cavity in an air floating mode through the air floating bearing; the air bearing at least comprises an upper air floating surface and a lower air floating surface, the upper air floating surface and the lower air floating surface are distributed at intervals along the axial direction of the stator, and the extending direction of the upper air floating surface is the same as that of the lower air floating surface. The substrate transfer device comprises at least three substrate transfer units arranged in the same direction and configured to move synchronously. So dispose, every substrate handing-over unit all independently includes stator and active cell, can independently adjust separately, has reduced the integrated degree of difficulty, has improved the integrated efficiency, and then has reduced substrate handing-over device's overall dimension, more does benefit to the subassembly structural layout, improves the stability and the reliability of product. In addition, the arrangement of the air bearing can limit the radial and circumferential degrees of freedom of the rotor, improve the driving precision of the substrate transfer unit and further improve the stability and reliability of the substrate transfer unit.

Drawings

It will be appreciated by those skilled in the art that the drawings are provided for a better understanding of the invention and do not constitute any limitation to the scope of the invention. Wherein:

FIG. 1 is a schematic cross-sectional view of a substrate interface unit along a longitudinal direction according to one embodiment of the present invention;

FIG. 2 is a schematic view of a stator of a substrate interface unit provided in accordance with one embodiment of the present invention;

fig. 3 is a schematic view of a mover of a substrate interface unit according to an embodiment of the present invention;

FIG. 4 is a schematic diagram illustrating the driving principle of a substrate transfer unit according to an embodiment of the present invention;

FIG. 5 is a schematic view of the plumbing connections of a substrate transfer unit provided in accordance with one embodiment of the present invention;

FIG. 6 is a schematic perspective view of a mover provided in an embodiment of the present invention;

fig. 7 is a schematic cross-sectional view of the mover shown in fig. 6 in a longitudinal direction;

FIG. 8 is a cross-sectional view of another substrate interface unit in a cross-sectional direction according to an embodiment of the present invention;

FIG. 9 is a schematic view of a substrate interface apparatus according to one embodiment of the invention.

In the drawings:

10-a substrate interface unit; 20-a wafer bearing platform; 30-a motion platform; 40-a substrate;

100-a stator; 110-lumen; 120-a coil; 121-a coil support; 130-ferromagnetic sleeve; 140-coolant flow channels; 141-coolant inlet; 142-a coolant outlet; 143-heat conducting glue; 150-a base; 160-jackscrew; 200-a mover; 210-a magnet; 220-back iron; 230-a fixed head; 240-air bearing shaft; 241-upper air floating surface; 242-lower air bearing surface; 2421-2424-son air bearing surface; 250-an air inlet; 251-an air inlet connector; 260-an air extraction port; 261-air extraction joint; 271-air extraction pipeline; 272-a gap; 300-a mechanical stop assembly; 311. 312-a stop; 321-upper limit proximity switch; 322-lower limit proximity switch; 400-grating scale assembly; 411-tape; 412-read head.

Detailed Description

To further clarify the objects, advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. It is to be noted that the drawings are in greatly simplified form and are not to scale, but are merely intended to facilitate and clarify the explanation of the embodiments of the present invention. Further, the structures illustrated in the drawings are often part of actual structures. In particular, the drawings may have different emphasis points and may sometimes be scaled differently.

As used in this specification, the singular forms "a," "an," and "the" include plural referents unless the content clearly dictates otherwise. As used in this specification, the term "or" is generally employed in its sense including "and/or" unless the content clearly dictates otherwise.

The invention provides a substrate transfer unit and a substrate transfer device, which are used for solving the problems that the transfer device in the prior art is large in size and easy to be interfered by an external magnetic field.

The following description refers to the accompanying drawings.

Referring to fig. 1 to 9, in which fig. 1 is a schematic cross-sectional view of a substrate cross-connecting unit according to an embodiment of the present invention along a longitudinal direction, fig. 2 is a schematic view of a stator of the substrate cross-connecting unit according to an embodiment of the present invention, fig. 3 is a schematic view of a mover of the substrate cross-connecting unit according to an embodiment of the present invention, fig. 4 is a schematic view of a driving principle of the substrate cross-connecting unit according to an embodiment of the present invention, fig. 5 is a schematic view of a pipeline connection of the substrate cross-connecting unit according to an embodiment of the present invention, fig. 6 is a schematic perspective view of the mover according to an embodiment of the present invention, fig. 7 is a schematic cross-sectional view of the mover shown in fig. 6 along the longitudinal direction, and fig. 8 is a schematic cross-sectional view of another substrate cross-connecting unit according to an embodiment of the present invention along a transverse direction; FIG. 9 is a schematic view of a substrate interface apparatus according to one embodiment of the invention.

As shown in fig. 1 to 7, an embodiment of the present invention provides a substrate interface unit, which includes: a stator 100 and a mover 200; the stator 100 includes a coil 120 and an inner cavity 110 arranged along an axial direction, the coil 120 is arranged around the inner cavity 110 in a circumferential direction; the mover 200 includes a magnet 210 and an air bearing, the magnet 210 is movably disposed in the inner cavity 110 along the axial direction of the stator 100, and the magnet 210 is configured to move along the axial direction of the stator 100 under the driving of the coil 120; the magnet 210 is air-float coupled to the inner chamber 110 via the air bearing. So dispose, every substrate handing-over unit all independently includes stator 100 and active cell 200, can independently adjust separately, has reduced the integrated degree of difficulty, has improved the integrated efficiency, and then has reduced substrate handing-over device's overall dimension, more does benefit to the subassembly structural layout, improves the stability and the reliability of product. In addition, the provision of the air bearings can restrict the degrees of freedom of the mover 200 in the radial direction and the circumferential direction, improve the driving accuracy of the substrate transfer unit, and further improve the stability and reliability of the substrate transfer unit.

The substrate interface unit provided in this embodiment is described below with reference to an exemplary embodiment.

Referring to fig. 1, the substrate interface unit mainly includes a stator 100 and a mover 200, the substrate interface unit is mainly configured to be disposed along a Z direction (e.g., a vertical direction), the inner cavity 110 of the stator 100 is also preferably disposed along the Z direction, and the mover 200 is capable of moving along the Z direction after being installed in the inner cavity 110, but is limited to have freedom degrees along the X direction and the Y direction. Alternatively, the mover 200 has a substantially cylindrical shape, and a fixing head 230 is disposed at a top end of the mover, and the fixing head 230 is used for adsorbing and supporting a substrate, such as a silicon wafer. Suitably, the inner cavity 110 of the stator 100 is also cylindrical, and the magnets 210 and the coils 120 are annular in cross-section. As shown in fig. 4, when the coil 120 cuts magnetic lines of force, when a current in a direction shown in fig. 4 passes through the coil 120, the magnetic lines of force in the substrate cross-connecting unit are shown by a dotted arrow in fig. 4, and the coil 120 generates an upward ampere force F in fig. 4 to the magnet 210, thereby driving the mover 200 to move. It is understood that when the direction of the current passing through the coil 120 is opposite, the mover 200 is driven to move in the opposite direction. Further, the substrate position can be adjusted by the movement of the mover 200.

As shown in fig. 3, preferably, the mover 200 includes back irons 220, and the back irons 220 are disposed at both ends of the magnet 210 in an axial direction of the stator 100. The magnet 210 is preferably made of a strong permanent magnetic material, such as neodymium iron boron, and the magnetization direction of the magnet 210 is Z-direction, i.e. the same as the moving direction of the mover 200. The back iron 220 is preferably fixedly connected to two ends of the magnet 210 along the Z direction, such as being adhered to the upper and lower ends of the magnet 210, and the back iron 220 is preferably made of a material with high saturation magnetic induction strength, such as iron-cobalt-vanadium soft magnetic alloy (1J 22). In some embodiments, the mover 200 includes an air floating shaft 240, and the magnet 210 and the back iron 220 may be fixedly disposed on the air floating shaft 240, such as by bonding, so as to form a magnetic circuit inside the mover 200. The back iron 220 is arranged to effectively improve the driving efficiency of the mover 200, reduce the interference of an external magnetic field to the mover 200, and further improve the stability and reliability of the substrate transfer unit.

Further, the air bearing at least includes an upper air floating surface 241 and a lower air floating surface 242, the upper air floating surface 241 and the lower air floating surface 242 are distributed at intervals along the axial direction of the stator 100, and the extending direction of the upper air floating surface 241 is the same as the extending direction of the lower air floating surface 242 (e.g., both extend along the Z direction). The two-section or multi-section air bearing spaced along the Z-direction can effectively constrain the degrees of freedom of the mover 200 in the X-direction, the Y-direction, the Rx-direction, and the Ry-direction, i.e., at least limit the degrees of freedom of the mover 200 in rotation around the X-axis and the Y-axis and the degrees of freedom in movement along the X-axis and the Y-axis. Further, the upper air bearing surface 241 has a ring shape, and the lower air bearing surface 242 includes two or more sub air bearing surfaces arranged at an angle in a radial direction of the stator 100. The sub air bearing surfaces of the lower air bearing surface 242 may limit the Rz degree of freedom of the mover 200, i.e., the rotational degree of freedom of the mover 200 about the Z axis, since they are angled in the radial direction of the stator 100. Thus, the mover 200 is restricted to have only the degree of freedom in the Z direction.

Preferably, the lower air bearing surface 242 includes a plurality of sub air bearing surfaces, and the centers of inscribed circles of at least three sub air bearing surfaces are located on the axis of the upper air bearing surface 241. FIGS. 3, 6, and 7 exemplarily show a mover 200 whose lower air bearing surface 242 includes four sub air bearing surfaces 2421-2424, each of which extends in the Z direction. The included angle between the sub-air-bearing surface 2421 and the sub-air-bearing surface 2424 is 120 degrees, the sub-air-bearing surface 2422 and the sub-air-bearing surface 2423 are on the same plane, and preferably, the included angle between the sub-air-bearing surface 2421 and the sub-air-bearing surface 2422 is 150 degrees. It should be noted that the included angle between the sub-air bearing surfaces is only illustrative and not limited to the included angle between the sub-air bearing surfaces, and those skilled in the art can also adopt other arrangement angles, such as 90 ° or 60 °. When the number of the sub-air bearing surfaces is three, it may be possible to clearly define an inscribed circle whose center is configured to be located on the axis of the upper air bearing surface 241. It is to be understood that the sub-air bearing surfaces are understood herein as planes that may be extended, and in fig. 3, 6, and 7, the inscribed circle defined by the four sub-air bearing surfaces may not be directly tangent to the

sub-air bearing surfaces

2422 and 2423, but may be tangent to the extended surfaces of the

sub-air bearing surfaces

2422 and 2423. When the number of the sub-air bearing surfaces is more than three, the circle centers of the inscribed circles of at least three sub-air bearing surfaces are ensured to be positioned on the axis of the upper air bearing surface 241, and other sub-air bearing surfaces can be tangent to the inscribed circles or not, and are not limited here. In an exemplary embodiment, the thickness of the air film on each sub-air-bearing surface of the upper air-bearing surface 241 and the lower air-bearing surface 242 is 10um to 15um, and the upper air-bearing surface 241 has 6 air-bearing holes, and the 6 air-bearing holes are preferably uniformly distributed around the circumferential direction. Each sub-air-bearing surface of the lower air-bearing surface 242 has 1 air-bearing hole. The air bearing holes and the air bearing film thickness of each air bearing surface can be configured according to the actual situation by a person skilled in the art.

Referring to fig. 5 and fig. 7, optionally, the mover 200 includes an air inlet 250 and an air suction port 260, the air inlet 250 is used for supplying air to the air bearing, and the air inlet 250 is connected to the stator 100 through a hose. The air suction port 260 is communicated with the fixing head 230 through an air suction pipeline 271 and used for sucking air from the fixing head 230, and the air suction port 260 is connected with the stator 100 through a hose. In the example shown in fig. 7, the air suction pipe 271 is disposed inside the mover 200, such as a stainless steel pipe, and a gap 272 is formed between the stainless steel pipe and the magnet 210 and the back iron 220, the gap 272 communicates the upper air floating surface 241 with the air inlet 250, and the dry compressed air is exhausted from the air inlet 250 through the air floating holes from the gap 272 to the upper air floating surface 241 to form an air film. Further, the stator 100 is provided with an air inlet connector 251 and an air exhaust connector 261, which are respectively used for connecting an external air supply end and an air exhaust end. Since the mover 200 needs to move in the Z direction, the air inlet 250 and the air exhaust port 260 are respectively connected to corresponding ports of the stator 100 through hoses to be respectively communicated with the air inlet connector 251 and the air exhaust connector 261.

As shown in fig. 1 and 2, the stator 100 preferably includes a ferromagnetic sleeve 130, and the ferromagnetic sleeve 130 covers at least the outer circumference of the coil 120. Optionally, the coil 120 is wound around the coil support 121 around the axis of the stator 100, and the coil support 121 is fixedly connected to the ferromagnetic sleeve 130. The ferromagnetic sleeve 130 wraps the outer circumference of the coil 120, and thus has a magnetic shielding effect, so that interference of an external magnetic field on the coil 120 and the magnet 210 can be reduced, and interference of the external magnetic field on the mover 200 can be reduced. Optionally, the ferromagnetic sleeve 130 is made of 2Cr13 stainless steel, which has high saturation magnetic induction. Referring to fig. 4, due to the arrangement of the ferromagnetic sleeve 130 and the back iron 220, magnetic lines of force in the substrate interface unit are closed and are not easily interfered by an external magnetic field.

Optionally, the stator 100 further includes a top thread 160, and the top thread 160 is disposed in the base 150, extends inward, and abuts against the ferromagnetic sleeve 130. The position of the ferromagnetic sleeve 130 relative to the base 150 can be adjusted by rotating the jackscrew 160, so that the axial position between the mover 200 and the stator 100 can be adjusted, and smooth air floatation is ensured. Preferably, the stator 100 includes a plurality of terminal wires 160, and the plurality of terminal wires 160 are uniformly distributed around the circumference of the stator 100.

Referring to fig. 4, further, the stator 100 includes a cooling liquid channel 140, and the cooling liquid channel 140 is used for flowing a cooling liquid to dissipate heat of the coil 120. Preferably, the stator 100 further includes a base 150, and the cooling fluid channel 140 is opened in the base 150 and at least partially overlaps with the coil 120 in the axial direction of the stator 100; the ferromagnetic sleeve 130 is thermally connected to the base 150, and the coil 120 is thermally connected to the ferromagnetic sleeve 130. The cooling liquid can be water, the cooling liquid flow channel 140 is added outside the coil 120 and flows through the cooling liquid, so that liquid cooling heat dissipation of the coil 120 can be effectively realized, high-precision components such as an exposure table and the like are prevented from being affected by thermal deformation or temperature drift, unstable output of a voice coil motor caused by overheating and demagnetization of the magnet 210 can be prevented, and the method has important significance for improving the precision of a photoetching machine. The ferromagnetic sleeve 130 and the base 150, and the coil 120 and the ferromagnetic sleeve 130 are connected by thermal conductive adhesive 143, and the ferromagnetic sleeve 130 and the base 150 may be connected by welding. As shown in fig. 5, a base 150 of the stator 100 may be provided with a cooling fluid inlet 141 and a cooling fluid outlet 142, which are respectively connected to an external cooling fluid circulation device for circulating a cooling fluid.

Optionally, the substrate interface unit further includes: the mechanical limiting assembly 300 includes two limiting members 311 and 312 disposed oppositely, the two limiting members 311 and 312 are disposed on the stator 100 and the mover 200, respectively, and the mechanical limiting assembly 300 is configured to limit an axial stroke of the mover 200 by abutting the two limiting members 311 and 312. Referring to fig. 1, in an exemplary embodiment, the limiting element 311 is disposed on the base 150 of the stator 100, and the limiting element 312 is disposed on the air floating shaft 240 of the mover 200, specifically, the limiting element 311 is a positioning pin, the limiting element 312 is a groove, the groove has a limiting surface facing the positioning pin, when the mover 200 reaches the limit position of the axial stroke, the limiting surface of the groove contacts and abuts against the positioning pin, and the positioning pin limits the mover 200 to continue moving, thereby limiting the axial stroke of the mover 200. Of course, the positioning pin-groove combination is only one example of the mechanical limiting assembly 300, and those skilled in the art may select other limiting members according to practical applications to achieve the mechanical limiting of the axial stroke of the mover 200. Due to the arrangement of the mechanical limiting assembly 300, the movement of the mover 200 is effectively prevented from exceeding the expected travel range, and the reliability of the substrate connection unit is improved. Preferably, the substrate interface unit further includes two VSO proximity switches, which are an upper limit proximity switch 321 and a lower limit proximity switch 322, respectively, and when the axial stroke of the mover 200 reaches a preset limit position, the two VSO proximity switches act to limit the axial stroke of the mover 200, thereby further improving the motion positioning control performance of the mover 200.

Optionally, the substrate interface unit further includes: the grating scale assembly 400 includes a scale tape 411 and a reading head 412, which are oppositely disposed, the scale tape 411 is disposed on the mover 200, the reading head 412 is disposed on the stator 100, and the grating scale assembly 400 is used for measuring an axial displacement of the mover 200 relative to the stator 100. The grating scale assembly 400 can accurately measure the axial displacement of the mover 200, and the coil 120 of the stator 100 can drive the mover 200 according to the measurement value fed back by the reading head 412, thereby ensuring accurate positioning between the stator 100 and the mover 200.

Referring to fig. 8, which is a cross-sectional view of another substrate interface unit of this embodiment along a transverse direction, wherein the magnet 210 and the coil 120 are square in cross-section, and the ferromagnetic sleeve 130 has a square inner contour to accommodate the coil 120. The cross-sections of the magnet 210, the coil 120 and the ferromagnetic sleeve 130 may be configured differently by those skilled in the art according to the practical application, and the present invention is not limited thereto.

Based on the above substrate transfer units, the present embodiment further provides a substrate transfer apparatus, which includes at least three substrate transfer units as described above, wherein the at least three substrate transfer units are arranged in the same direction and configured to move synchronously. The following describes a detailed description of the synchronous movement of the substrate transfer units by way of an exemplary substrate transfer apparatus including three substrate transfer units.

Referring to fig. 9, the substrate transfer apparatus includes three substrate transfer units 10 (only two are shown in fig. 9 due to a cross-sectional view) and a moving platform 30, wherein the three substrate transfer units 10 are respectively fixedly disposed on the moving platform 30 for supporting and adsorbing a substrate 40 carried on a substrate support 20. The synchronized movement of the three substrate interface units 10 includes the steps of:

a reference zero is set for three substrate interface units 10: firstly, a substrate 40 is vacuum-absorbed on the wafer bearing table 20, and the bottom surface of the substrate 40 is set as a substrate mounting surface; respectively applying force to the motor of each substrate handover unit 10 to jack the motor on the bottom surface of the substrate 40, and respectively recording the distance from the reference point of the grating ruler to the bottom surface of the substrate 40;

the substrate mounting surface then serves as a reference zero for the three substrate interface units 10. During the movement of the three substrate transfer units 10, the same displacement is maintained with respect to the reference zero position, so that the three substrate transfer units 10 can be moved synchronously at the same height at the moment of substrate transfer.

Preferably, at least three substrate interface units are each disposed along the Z-direction. More preferably, the substrate interface units are evenly distributed circumferentially around a central axis of the substrate interface device. In one example, the substrate transfer device includes three substrate transfer units, wherein the three substrate transfer units are all located at an angle of 120 ° with respect to a central axis of the substrate transfer device, and the three substrate transfer units are located at equal distances from the central axis of the substrate transfer device. Of course, the substrate interface device may be configured appropriately by those skilled in the art, such as selecting a greater number of substrate interface units or arranging the substrate interface units differently. Since the substrate transfer apparatus provided in this embodiment includes the substrate transfer unit as described above, which also has the beneficial effects brought by the substrate transfer unit, the structure and principle of other modules of the substrate transfer apparatus are not described in detail herein.

The above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention, and any variations and modifications made by those skilled in the art based on the above disclosure are within the scope of the appended claims.

Claims

1. A substrate interface unit, comprising: a stator and a mover;

2. The substrate interface unit of claim 1, wherein the upper air-bearing surface is annular and the lower air-bearing surface comprises two or more sub air-bearing surfaces arranged at an angle in a radial direction of the stator.

3. The substrate interface unit of claim 2, wherein the lower air-bearing surface comprises a plurality of sub-air-bearing surfaces, at least three of the sub-air-bearing surfaces having inscribed circles centered on the axis of the upper air-bearing surface.

4. The substrate interface unit of claim 1, wherein the mover comprises an air inlet for supplying air to the air bearings, the air inlet being coupled to the stator by a hose.

5. The substrate interface unit of claim 1, wherein the mover includes back irons disposed at both ends of the magnet in an axial direction of the stator.

6. The substrate interface unit of claim 1, wherein the stator comprises a ferromagnetic sleeve and a base, the ferromagnetic sleeve at least covers the outer periphery of the coil, the base having a coolant flow channel formed therein, the coolant flow channel at least partially overlapping the coil in an axial direction of the stator; the ferromagnetic sleeve is in heat conduction connection with the base, and the coil is in heat conduction connection with the ferromagnetic sleeve.

7. The substrate interface unit of claim 1, wherein the mover comprises a fixed head for adsorbing and supporting a substrate and an air suction port communicating with the fixed head through an air suction line for sucking air from the fixed head, the air suction port being connected to the stator through a hose.

8. The substrate interface of claim 1, further comprising: the mechanical limiting assembly comprises two limiting parts which are arranged oppositely, the two limiting parts are arranged on the stator and the rotor respectively, and the mechanical limiting assembly is used for limiting the axial stroke of the rotor through the abutting of the two limiting parts.

9. The substrate interface of claim 1, further comprising: the grating scale assembly comprises a scale belt and a reading head which are oppositely arranged, the scale belt is arranged on the rotor, the reading head is arranged on the stator, and the grating scale assembly is used for measuring the axial displacement of the rotor relative to the stator.

10. A substrate interface apparatus, comprising: at least three substrate interface units according to any one of claims 1 to 9, arranged in the same direction and configured to move in synchronism.