Substrate transfer mechanism and exposure stage system

Abstract

The present invention relates to the field of semiconductor technology, and provides a substrate handover mechanism and an exposure platform system, wherein the substrate handover mechanism includes: a rotating seat, an adsorption assembly, a base, and a rotating drive member; the rotating seat is mounted on the base in a manner that it can rotate along its own central axis, and the base is used to be mounted on a workbench of the exposure platform system; the adsorption assembly is arranged on the rotating seat for adsorbing the wafer; the rotating drive member is arranged on the base for driving the rotating seat to rotate around its own central axis. With such a configuration, the substrate handover mechanism and the exposure system only need to adaptively drive the rotating seat in the substrate handover mechanism to rotate when compensating for the circumferential position error of the wafer, and do not need to drive the entire exposure system to rotate as a whole, which is conducive to simplifying the rotation structure, improving the input-output ratio, and achieving higher rotation accuracy.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor technology, and in particular to a substrate handover mechanism and an exposure platform system. Background Art

[0002] The wafer exposure process uses light to project the pattern on the mask through an optical system onto the photoresist, achieving pattern transfer. Exposure is a critical step in the photolithography process for integrated circuit manufacturing. During exposure, the wafer is placed on the wafer stage using a substrate transfer mechanism. The accuracy of the wafer's placement on the stage directly impacts exposure quality.

[0003] After the wafer is placed on the wafer stage, it is usually necessary to rotate the wafer around the central axis in the vertical direction to compensate for the circumferential position error of the wafer. At present, the substrate transfer mechanism is generally installed on the wafer stage, and the substrate transfer mechanism only has the vertical lifting function, and the circumferential error of the wafer is compensated by the overall rotation of the exposure stage. Since the overall structure of the exposure stage is relatively complex and occupies a large space, the overall size and mass of the equipment are relatively large. Therefore, if the overall rotation of the exposure stage is realized, on the one hand, its rotation accuracy is difficult to control, the cost required to realize the rotation is high, and it is also difficult to realize the overall rotation of the exposure stage.

[0004] Therefore, there is an urgent need for a substrate transfer mechanism and an exposure stage system, so that the substrate transfer mechanism itself has a rotation compensation function, thereby eliminating the need for the exposure stage to rotate as a whole. Summary of the Invention

[0005] The invention provides a substrate handover mechanism and an exposure table system. When compensating for the circumferential position error of the wafer, it is only necessary to adaptively drive the rotating seat in the substrate handover mechanism to rotate, and there is no need to drive the entire exposure system to rotate. On the one hand, it is conducive to simplifying the rotation structure to reduce the hardware cost or R&D cost required for compensating for the circumferential position error of the wafer, thereby improving the input-output ratio. On the other hand, the overall size and mass of the entire rotation drive structure are reduced, which is conducive to achieving higher rotation accuracy.

[0006] The substrate transfer mechanism includes: a rotating seat, an adsorption component, a base and a rotating drive member;

[0007] The rotating seat is mounted on the base in a manner that it can rotate along its own central axis, and the base is used to be mounted on the workbench of the exposure table system;

[0008] The adsorption component is arranged on the rotating seat for adsorbing the wafer;

[0009] The rotation driving member is arranged on the base and is used to drive the rotating seat to rotate around its own central axis.

[0010] Optionally, the base has a circular mounting cavity, and the rotating seat is coaxially mounted in the mounting cavity.

[0011] Optionally, the adsorption component includes a suction nozzle, and the suction nozzle is used to adsorb the wafer.

[0012] Optionally, the rotating drive member includes a first drive member and a second drive member, the first drive member is arranged on the base, and the second drive member is arranged on the rotating seat, and the first drive member is used to apply a driving force to the second drive member in a non-contact manner, and the driving force causes the second drive member to move linearly along a set direction, and the set direction is tangent to the rotation direction of the rotating seat.

[0013] Optionally, one end of the rotating seat is located in the installation cavity, and the other end of the rotating seat is provided with a groove, and the adsorption assembly is installed in the groove.

[0014] Optionally, along a direction perpendicular to the central axis of the rotating seat, the groove overlaps with a projection of the mounting cavity.

[0015] Optionally, the substrate handover mechanism further includes a bearing, the outer ring of the bearing is fixedly matched with the inner wall of the installation cavity, and the inner ring of the bearing is fixedly matched with the outer peripheral surface of the rotating seat.

[0016] Optionally, the substrate handover mechanism further comprises an elastic member, which is used to provide a preload force along a radial direction for the inner ring of the bearing, and the preload force causes the inner ring of the bearing to approach the outer ring of the bearing along the radial direction.

[0017] Optionally, the substrate handover mechanism also includes a bearing limiter, the upper end of the mounting cavity has an annular mounting groove that expands radially, the outer ring of the bearing is conformally mounted in the annular mounting groove and abuts against the axial side wall of the annular mounting groove, and the bearing limiter is arranged on the base and presses the bearing axially into the annular mounting groove.

[0018] Optionally, the suction end of the suction nozzle is located on a side away from the rotating base along a first direction, and the suction nozzle is arranged on the rotating base in a manner that can be raised and lowered along the first direction, and the first direction is parallel to the central axis of the rotating base itself.

[0019] Optionally, the substrate handover mechanism further includes a vertical limiting mechanism, and the vertical limiting mechanism is used to limit the lifting height of the suction nozzle.

[0020] Optionally, the adsorption assembly further includes several adsorption racks, the adsorption racks include a support plate, a first air duct is provided on the support plate, at least two suction nozzles are installed on the side of the support plate away from the base along the first direction, and the inner cavity of the suction nozzle is connected to the first air duct.

[0021] Optionally, the adsorption rack further includes a suction column, which is connected to the support plate, the suction column extends along a first direction, the support plate extends along a direction perpendicular to the first direction, and a second air channel is provided on the suction column, which is connected to the first air channel.

[0022] Optionally, the adsorption assembly also includes an adsorption base, each of the adsorption racks is arranged on the adsorption base, and the adsorption base is arranged on the rotating seat in a manner that it can be raised and lowered along the first direction to achieve synchronous lifting and lowering of each suction nozzle, and the adsorption ends of each suction nozzle are arranged in the same plane.

[0023] Optionally, an air suction channel is provided on the adsorption base, and the air suction channel is connected to the first air channel corresponding to each adsorption rack.

[0024] Optionally, the adsorption assembly further includes a plurality of adsorption bases, each of the adsorption bases is matched with each of the adsorption racks one by one, each of the adsorption bases can be installed on the rotating seat so as to be lifted and lowered along the first direction, and each of the adsorption bases is equipped with a vertical driving member for independent lifting and lowering drive.

[0025] Optionally, the substrate handover mechanism further includes a rotation limiting mechanism, and the rotation limiting mechanism is used to limit the rotation angle of the rotating seat.

[0026] Optionally, the rotation limiting mechanism includes a circumferential grating scale and a rotation limit sensor, the circumferential grating scale is arranged on the base for detecting the angular displacement of the rotating seat, and the rotation limit sensor is used to receive the angular displacement detected by the circumferential grating scale and to limit the rotation angle of the rotating seat.

[0027] The present invention also provides an exposure system, which is equipped with the above-mentioned substrate handover mechanism.

[0028] Optionally, the exposure system further includes a wafer stage, and the adsorption component of the substrate handover mechanism can be raised and lowered relative to the wafer stage along the direction of the central axis of the rotating seat, and the adsorption component of the substrate handover mechanism can be rotated relative to the wafer stage with the central axis of the rotating seat as the center, and a through hole is provided on the wafer stage for the adsorption component to pass through when being raised and lowered.

[0029] The present invention also provides a wafer handover method, comprising the following steps:

[0030] S1: Raise the adsorption assembly so that the adsorption assembly extends through the through hole on the wafer stage;

[0031] S2: The adsorption component receives and adsorbs the wafer;

[0032] S3: lowering the adsorption assembly so that the wafer is placed on the wafer stage;

[0033] S4: Check whether the circumferential position error of the chip meets the requirements; if it does, the chip handover is completed; if it does not meet the requirements, the adsorption component is raised, the rotating seat rotates and drives the adsorption component to rotate to compensate for the circumferential position error of the chip, and step S3 is executed again.

[0034] To summarize, the substrate handover mechanism includes: a rotating seat, an adsorption assembly, a base, and a rotating drive member; the rotating seat is mounted on the base in a manner that it can rotate along its own central axis, and the base is used to be mounted on the workbench of the exposure table system; the adsorption assembly is arranged on the rotating seat for adsorbing the wafer; the rotating drive member is arranged on the base for driving the rotating seat to rotate around its own central axis.

[0035] With such a configuration, the substrate handover mechanism and the exposure system only need to adaptively drive the rotating seat in the substrate handover mechanism to rotate when compensating for the circumferential position error of the wafer, and there is no need to drive the entire exposure system to rotate as a whole. On the one hand, it is conducive to simplifying the rotation structure to reduce the hardware cost or R&D cost required for compensating for the circumferential position error of the wafer, thereby improving the input-output ratio. On the other hand, it makes the overall size and mass of the entire rotation drive structure smaller, which is conducive to achieving higher rotation accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Schematic diagram of the structure of an exposure system according to an embodiment of the present invention;

[0037] Figure 2 A schematic diagram of the principle structure of an exposure system according to an embodiment of the present invention;

[0038] Figure 3 Schematic diagram of the assembly structure of the substrate transfer mechanism and the wafer stage according to one embodiment of the present invention;

[0039] Figure 4 A schematic diagram of the principle structure of a substrate transfer mechanism according to an embodiment of the present invention;

[0040] Figure 5 A schematic structural diagram of a substrate transfer mechanism according to an embodiment of the present invention;

[0041] Figure 6 Schematic diagram of the exploded structure of a substrate transfer mechanism according to one embodiment of the present invention;

[0042] Figure 7 Schematic diagram of the structure of the adsorption component of the substrate transfer mechanism according to one embodiment of the present invention;

[0043] Figure 8 FIG. 1 is a flow chart of wafer transfer according to an embodiment of the present invention.

[0044] The accompanying drawings are numerals as follows:

[0045] 10-rotating seat; 11-groove; 12-avoidance groove; 13-mounting ear;

[0046] 20-adsorption component; 21-suction nozzle; 22-support plate; 221-first air channel; 23-suction column; 231-second air channel; 24-adsorption base; 241-suction channel;

[0047] 30-base; 31-mounting cavity; 311 mounting slot;

[0048] 40-rotation driving member; 41-coil; 42-electromagnet;

[0049] 50-bearing;

[0050] 60- elastic member;

[0051] 711 - Circumferential grating ruler; 712 - Rotation limit sensor; 721 - Vertical mechanical limiter; 722 - Vertical grating ruler; 723 - Vertical electrical limit sensor; 724 - Vertical buffer pad; 73 - Bearing limiter; 74 - Lifting drive; 741 - Vertical guide rail; 742 - Vertical motor; 75 - Flexible cable;

[0052] 80-chip support; 81-through hole;

[0053] 90 - workbench; 91 - X-axis mechanism; 911 - X-axis guide rail; 92 - Y-axis mechanism; 921 - Y-axis guide rail; 922 - first Y-axis motor; 923 - second Y-axis motor; 93 - laser interferometer; 94 - wafer;

[0054] 100-substrate handover mechanism;

[0055] Z-first direction; X-second direction; Y-third direction; a-central axis of the rotating seat.

[0056] As used in the present invention, the singular forms "a," "an," and "the" include plural referents. The term "or" is generally used to include "and / or," the term "several" is generally used to include "at least one," and the term "at least two" is generally used to include "two or more." Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Thus, features defined as "first," "second," and "third" may explicitly or implicitly include one or at least two of the features. Furthermore, as used in the present invention, the terms "mounted," "connected," and "connected," or "an element being "disposed" on another element, should be understood broadly and generally only indicate a connection, coupling, mating, or transmission relationship between the two elements, which can be direct or indirect through an intermediate element. They should not be understood to indicate or imply a spatial positional relationship between the two elements, i.e., one element can be located inside, outside, above, below, or to the side of another element, unless the context clearly indicates otherwise. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, directional terms such as above, below, up, down, upward, downward, left, right, etc. are used with respect to the exemplary embodiments as they are shown in the figures, with the upward or upper direction being toward the top of the corresponding figure and the downward or lower direction being toward the bottom of the corresponding figure.

[0057] The wafer exposure process uses light to project the pattern on the mask through an optical system onto the photoresist, achieving pattern transfer. It is a key step in the photolithography process for integrated circuit manufacturing. During exposure, the wafer is placed on the wafer stage using a substrate transfer mechanism. The positioning accuracy of the wafer on the wafer stage directly affects the exposure quality.

[0058] After the wafer is placed on the wafer stage, it is usually necessary to rotate the wafer around the central axis in the vertical direction to compensate for the circumferential position error of the wafer. At present, the substrate transfer mechanism is generally installed on the wafer stage, and the substrate transfer mechanism only has the vertical lifting function, and the circumferential error of the wafer is compensated by the overall rotation of the exposure stage. Since the overall structure of the exposure stage is relatively complex and occupies a large space, the overall size and weight of the equipment are relatively large. Therefore, if the overall rotation of the exposure stage is realized, on the one hand, its rotation accuracy is difficult to control, the cost required to realize the rotation is high, and it is also difficult to realize the overall rotation of the exposure stage.

[0059] Therefore, the present invention proposes a substrate handover mechanism and an exposure table system. When compensating for the circumferential position error of the wafer, it is only necessary to adaptively drive the rotating seat 10 in the substrate handover mechanism to rotate, and there is no need to drive the entire exposure system to rotate as a whole. On the one hand, it is beneficial to simplify the rotating structure to reduce the hardware cost or R&D cost required for compensating for the circumferential position error of the wafer, thereby improving the input-output ratio. On the other hand, it makes the overall size and mass of the entire rotating drive structure smaller, which is conducive to achieving higher rotation accuracy.

[0060] In the following embodiments, the first direction Z, the second direction X, and the third direction Y are perpendicular to each other; the radial direction and the axial direction are based on the rotating base 10, and the axial direction of the rotating base 10 is parallel to the first direction Z.

[0061] Example 1:

[0062] This embodiment provides an exposure system, which includes a substrate transfer mechanism 100, a wafer stage 80 and a workbench 90;

[0063] Please refer to Figure 1 and Figure 2 As shown, the substrate handover mechanism 100 is provided on the workbench 90, and the substrate handover mechanism is located between the wafer stage 80 and the workbench 90. The substrate handover mechanism 100 partially passes through the wafer stage 80. The wafer stage 80 can move on the workbench 90 in a direction perpendicular to the central axis of the rotating base 10 itself, and the substrate handover mechanism 100 follows the movement of the wafer stage 80. The specific structure of the substrate handover mechanism 100 is described in detail below. The wafer stage 80 and the substrate handover mechanism 100 are integrated. When the wafer stage 80 moves along the workbench 90, the substrate handover mechanism 100 follows the movement.

[0064] The wafer table 80 is moved along the second direction X and the third direction Y on the workbench 90 by a sliding mechanism. Figure 1 and Figure 2 As shown, an X-direction mechanism 91 and a Y-direction mechanism 92 are provided on the workbench 90, wherein the X-direction mechanism 91 includes an X-direction guide rail 911 and an X-direction motor. The X-direction guide rail 911 extends along the second direction X, wherein the wafer stage 80 is provided on the X-direction guide rail 911 and can be driven by the X-direction motor to perform stepping motion along the second direction X with a long stroke; wherein the Y-direction mechanism 92 includes a Y-direction guide rail 921 and a first Y-direction motor 922 and a second Y-direction motor 923. Two Y-direction guide rails 921 are provided in parallel and extend along the third direction Y, wherein both ends of the X-direction guide rail 911 are respectively provided on the two Y-direction guide rails 921 so as to be movable along the third direction Y, and the first Y-direction motor 922 and the second Y-direction motor 923 are respectively used to drive the two ends of the X-direction guide rail 911 so as to enable the X-direction guide rail 911 to perform stepping motion along the third direction Y with a long stroke.

[0065] In order to facilitate the detection of the moving position of the substrate handover mechanism 100 along the second direction X and the third direction Y, in this embodiment, a displacement detection mechanism is further provided on the workbench 90. The displacement detection mechanism adopts a laser interferometer 93. The laser interferometer 93 is provided with two groups respectively facing the wafer stage 80 along the second direction X and the third direction Y, and is used to detect the displacement of the wafer stage 80 along the second direction X and the third direction Y, and then obtain the real-time position of the substrate handover mechanism 100 on the workbench. Since the substrate handover mechanism 100 moves with the wafer stage 80, the position of the substrate handover mechanism 100 can be indirectly obtained.

[0066] Please combine Figure 3 and Figure 4 As shown, the substrate handover mechanism 100 includes: a rotating seat 10, an adsorption assembly 20, a base 30, a rotating drive member 40 and a bearing 50; the rotating seat 10 is mounted on the base 30 in a manner that it can rotate along its own central axis a; the adsorption assembly 20 includes a suction nozzle 21, and the suction nozzle 21 can be directly or indirectly arranged on the rotating seat 10 through an intermediate connecting member for adsorbing the wafer; the rotating drive member 40 is arranged on the base 30 for driving the rotating seat 10 to rotate around its own central axis a.

[0067] The adsorption end of the suction nozzle 21 is located on the side away from the rotating seat 10 along the first direction Z. The suction nozzle 21 is set on the rotating seat 10 in a manner that it can be raised and lowered along the first direction Z. The first direction Z is parallel to the central axis a of the rotating seat 10 itself. The wafer support table 80 is provided with a through hole for the adsorption component to pass through when it is raised and lowered, and further provides a through hole 81 for the suction nozzle 21 to pass through when it is raised and lowered.

[0068] The suction nozzle 21 is used to adsorb the wafer 94. When the suction nozzle 21 is raised along the first direction Z, the suction nozzle 21 is lifted upward through the through hole 81, and the suction nozzle 21 is higher than the wafer stage 80 for receiving and adsorbing the wafer 94. Then the suction nozzle 21 is lowered along the first direction Z, and the wafer is placed on the wafer stage 80. The circumferential installation error of the wafer is detected by the alignment mechanism. If the circumferential posture of the wafer does not meet the accuracy requirements, the suction nozzle 21 needs to be raised again along the first direction Z, and the rotating seat 10 and the adsorption component 20 are rotated by the rotating drive member 40 to compensate for the circumferential posture of the wafer 94; then the suction nozzle 21 is lowered along the first direction Z, and the wafer 94 with the compensated posture is continued to be transferred to the wafer stage, and the circumferential installation error of the wafer is detected again by the alignment mechanism, and so on, until the circumferential installation error of the wafer meets the requirements. During the actual adjustment process, the circumferential installation error of the chip 94 is extremely small, so the rotation adjustment angle required by the rotating seat 10 and the adsorption component 20 is extremely small. Therefore, the circumferential displacement of the suction nozzle 21 relative to the wafer support table 80 is small, so it is only necessary to properly control the inner diameter size of the through hole 81 to ensure that the suction nozzle 21 does not interfere with the inner wall of the through hole 81 during axial movement.

[0069] Furthermore, the rotating drive member 40 includes a first drive member and a second drive member, the first drive member is arranged on the base 30, and the second drive member is arranged on the rotating seat 10, and the first drive member is used to apply a driving force to the second drive member in a non-contact manner, and the driving force causes the second drive member to move linearly along a set direction, and the set direction is tangent to the rotation direction of the rotating seat 10.

[0070] Please combine Figure 4 and Figure 5 As shown, the rotating driving member 40 in this embodiment is driven by a linear motor, wherein the first driving member is the electromagnet 42 of the linear motor, the electromagnet 42 is arranged on the base 30, and the second driving member is the coil 41 of the linear motor, the coil 41 is connected to the rotating seat 10, and the movement direction of the coil 41 driven by the electromagnet is tangent to the rotation direction of the rotating seat 10, and the rotating seat 10 is driven to achieve a smaller rotation angle through a small linear motion, and the linear motion of the coil 41 naturally limits the rotation angle of the rotating seat 10.

[0071] In other alternative embodiments, the first driving member and the second driving member may both adopt an electromagnet structure, or the first driving member may adopt a permanent magnet and the second driving member may adopt an electromagnet, or other known non-contact driving structures may be adopted, which will not be described here one by one.

[0072] In addition, in other alternative embodiments, the rotating drive member 40 may also adopt a rotating motor, whose motor rotor is in transmission cooperation with the rotating base 10 , and the stator of the motor is fixedly connected to the base 30 to realize the rotation drive of the rotating base 10 .

[0073] In this structure, when compensating for the circumferential position error of the wafer, the substrate handover mechanism and the exposure system only need to adaptively drive the rotating seat 10 in the substrate handover mechanism to rotate, and there is no need to drive the entire exposure system to rotate as a whole. On the one hand, it is beneficial to simplify the rotation structure to reduce the hardware cost or R&D cost required for compensating for the circumferential position error of the wafer, thereby improving the input-output ratio. On the other hand, it makes the overall size and mass of the entire rotation drive structure smaller, which is conducive to achieving higher rotation accuracy.

[0074] Please combine Figures 4 to 6 As shown, the base 30 has a circular mounting cavity 31, and the rotating seat 10 is coaxially mounted within the mounting cavity 31. The outer ring of the bearing 50 is fixedly fitted with the inner wall of the mounting cavity 31, and the inner ring of the bearing 50 is fixedly fitted with the outer peripheral surface of the rotating seat 10. Specifically, the outer ring of the bearing 50 and the inner wall of the mounting cavity 31 can be fitted by an interference fit, and similarly, the inner ring of the bearing 50 and the outer peripheral surface of the rotating seat 10 can be fitted by an interference fit. In this embodiment, the bearing 50 is a crossed roller bearing, which has excellent rotational accuracy and can meet the requirements for wafer rotation accuracy. The internal structure of the crossed roller bearing uses rollers arranged perpendicularly at 90 degrees to each other. Spacers or isolation blocks are installed between the rollers to prevent the rollers from tilting or rubbing against each other, effectively preventing an increase in rotational torque. In addition, the bearing will not have one-sided contact or locking of the rollers; at the same time, because the inner and outer rings are separated structures, the gap can be adjusted, and high-precision rotational motion can be obtained even if pre-load is applied; through this installation structure, the overall high installation accuracy and rotation accuracy of the rotating seat 10 can be guaranteed.

[0075] Please combine Figure 4 and Figure 6 As shown, further, the substrate handover mechanism also includes a bearing limiter 73, the upper end of the mounting cavity 31 has a radially enlarged annular mounting groove 311, the outer ring of the bearing 50 is conformally mounted in the annular mounting groove 311 and abuts against the axial side wall of the annular mounting groove 311, and the bearing limiter 73 is arranged on the base 30 and presses the bearing 50 axially into the annular mounting groove 311.

[0076] The bearing stopper 73 cooperates with one axial side of the annular mounting groove 311 to axially limit the bearing 50. The specific structure of the bearing stopper 73 is not particularly limited herein. In this embodiment, multiple bearing stoppers 73 are provided and are equidistantly spaced circumferentially around the mounting cavity 31. Each bearing stopper 73 cooperates to uniformly press against the bearing 50 circumferentially. In other alternative embodiments, for example, the bearing stopper 73 may be an annular structure. In this case, the bearing stopper 73 can continuously press against the bearing 50 circumferentially.

[0077] Please continue to combine Figures 4 to 6 As shown, further, one end of the rotating seat 10 is located in the installation cavity 31, and the other end of the rotating seat 10 is provided with a groove 11, and the adsorption assembly 20 is installed in the groove 11; along the direction perpendicular to the central axis of the rotating seat 10, the groove 11 coincides with the projection of the installation cavity 31. The groove 11 is a circular structure as a whole and the groove 11 is coaxial with the rotating seat 10. In order to adapt to the structure of the adsorption assembly 20, some avoidance grooves 12 are adaptively opened on the inner wall of the groove 11 to prevent the groove from interfering with the adsorption assembly 20. Through this structure, on the one hand, it is convenient to install the adsorption assembly 20, reduce the overall height of the substrate handover mechanism 100, and thus adapt to the size of the existing exposure system. On the other hand, it is also convenient to lower the center of gravity of the entire substrate handover mechanism 100, thereby improving the stability of the substrate handover mechanism 100.

[0078] Please refer to Figure 4 and Figure 5 As shown, the substrate handover mechanism further includes an elastic member 60, which is used to provide a preload force along a radial direction for the inner ring of the bearing 50. The preload force causes the inner ring of the bearing 50 to approach the outer ring of the bearing 50 along the radial direction. In this embodiment, the elastic member 60 is a preload spring, specifically a cylindrical coil spring or other type of spring structure. One end of the elastic member 60 is connected to the base 30, and the other end is connected to the inner ring of the bearing 50. The elastic member 60 is in a stretched state along a radial direction of the rotating seat 10, thereby radially pulling the inner ring of the bearing 50 so that the inner circle of the bearing approaches the outer circle of the bearing in the radial direction, thereby eliminating the gap between the inner and outer rings of the cross-roller bearing. In summary, by combining the above-mentioned rotating drive member with the corresponding rotating structure, circumferential reciprocating precision motion of approximately 10 mrad can be achieved.

[0079] Please refer to Figures 5 to 7As shown, the adsorption assembly 20 also includes a number of adsorption racks and an adsorption base 24, the adsorption rack includes a support plate 22 and a suction column 23, the support plate 22 extends in a direction perpendicular to the first direction Z, and a first air duct 221 is provided on the support plate 22 along the second direction X, and at least two suction nozzles 21 are installed on the side of the support plate 22 away from the base 30 along the first direction Z, and each suction nozzle 21 is arranged along the length direction of the support plate 22; the suction column 23 extends along the first direction Z, and the suction column 23 is vertically connected to the support plate 22, a second air duct 231 is provided on the suction column 23, and a seal is provided at the connection between the suction column 23 and the support plate 22, so that the second air duct 231 is sealed and connected to the first air duct 221; the inner cavity of the suction nozzle 21 is connected to the first air duct 221.

[0080] Please refer to Figure 5 As shown, in this embodiment, four suction racks are provided. The support plates 22 of the four suction racks extend in the same direction, and each of the four support plates 22 is provided with two suction nozzles 21. In other alternative embodiments, the number of suction racks and suction nozzles 21 installed on each support plate 22 can be adjusted based on the needs of use, which will not be described in detail here. The suction nozzles 21 are preferably made of an elastic material and are used to assist in the suction of wafers. Suction nozzles made of elastic materials are particularly suitable for assisting the suction of warped wafers.

[0081] The support plate 22 is a rectangular structure as a whole. Accordingly, the through hole 81 on the wafer support table 80 is opened as a rectangular hole. The outline size of the through hole 81 is larger than the outer size of the support plate 22, so that when the support plate 22 is located in the through hole 81, the support plate 22 is allowed to rotate slightly with the rotating seat 10 without interfering with the inner wall of the through hole 81, and the width of the through hole 81 is larger than the outer diameter of the suction column 23. When the suction nozzle 21 is raised, the suction column 23 is located in the through hole 21, and at this time, the suction column 23 is allowed to rotate slightly with the rotating seat 10 without interfering with the inner wall of the through hole 81.

[0082] Please continue to refer to 5 and Figure 6As shown, each adsorption rack is arranged on the adsorption base 24. The adsorption base 24 is arranged on the rotating base 10 in a manner that can be raised and lowered along the first direction Z to achieve synchronous lifting and lowering of each suction nozzle 21. The adsorption base 24 can be an integrated disc-shaped structure or a frame structure. In this embodiment, the adsorption base 24 adopts a rectangular frame structure. The suction columns 23 of each adsorption rack are respectively connected to the four corners of the adsorption base 24. Based on the assembly method of the adsorption base 24 and the lifting structure, a crossbeam can be adaptively added between the frames of the adsorption base 24. The adsorption base 24 with this structure meets the requirements of lightweight design. The adsorption ends of the corresponding suction nozzles 21 on each adsorption rack are arranged in the same plane; wherein a lifting drive member 74 is arranged on the base 30, wherein the lifting drive member includes a vertical guide rail 741 and a vertical motor 742, wherein the vertical guide rail 741 extends along the first direction Z, and the adsorption base 24 is arranged on the vertical guide rail 741 so as to be movable along the first direction Z, and the vertical motor 742 is used to drive the adsorption base 24 to move along the first direction Z on the vertical guide rail 741, thereby driving each adsorption rack and the suction nozzle 21 to rise and fall synchronously. Furthermore, preferably, there are two or more vertical guide rails 741, and the adsorption base 24 is simultaneously arranged on each vertical guide rail 741 so as to be movable along the first direction Z. In combination with the auxiliary adsorption of multiple suction nozzles 21, the horizontal and vertical repeat positioning accuracy of the substrate handover mechanism 100 during handover is ensured, thereby ensuring the feasibility of using the rotational movement of the substrate handover mechanism 100 to compensate for the circumferential error of the wafer loading.

[0083] The suction base 24 is provided with an air suction channel 241, which communicates with the first air channel 221 corresponding to each suction rack. The air suction channel 241 is connected to a vacuum pump. When the vacuum pump draws air, a negative pressure environment is created in the air suction channel 241, the first air channel 221, and the second air channel 231. This in turn creates a negative pressure environment at the suction nozzle 21, allowing for wafer suction.

[0084] Please refer to Figures 4 to 6 As shown, in this embodiment, the substrate transfer mechanism 100 further includes a rotation limiting mechanism and a vertical limiting mechanism;

[0085] The rotation limit mechanism includes a circumferential grating scale 711 and a rotation limit sensor 712, wherein the circumferential grating scale 711 is arranged on the base 30 to detect the angular displacement of the rotating seat 10, and the rotation limit sensor 712 is used to receive the angular displacement detected by the circumferential grating scale 711 and to limit the rotation angle of the rotating seat 10. Through the cooperation of the circumferential grating scale 711 and the rotation limit sensor 712, the angular displacement of the rotating seat 10 can be accurately detected, thereby ensuring a higher accuracy during the chip rotation compensation.

[0086] To facilitate the installation of the rotation limit sensor 712 and the coil 41 of the rotating drive member 40, two protruding mounting ears 13 are provided at the outer edge of the rotating seat 10, wherein the limit sensor 712 is installed on one of the mounting ears, and the coil 41 is connected to the other mounting ear to achieve a better spatial layout.

[0087] The vertical limit mechanism includes a vertical mechanical limiter 721, a vertical grating ruler 722, and a vertical electrical limit sensor 723. The vertical mechanical limiter 721 is disposed on the base 30 to limit the elevated position of the suction nozzle 21. Specifically, the vertical mechanical limiter 721 can be a limit block that limits its elevated position by interfering with the suction base 24. The vertical grating ruler 722 is disposed on the base 30 and faces the suction base 24 along the first direction Z to detect the elevated position of the suction nozzle 21. The vertical electrical limit sensor 723 is used to limit the elevation travel of the suction nozzle 21. When the travel exceeds this travel, the vertical electrical limit sensor 723 controls the vertical motor 742 to stop, achieving electrical locking. In summary, the substrate handover mechanism 100 ensures the horizontal and vertical repeat positioning accuracy of the substrate handover mechanism 100 during handover through multiple sets of vertical guide rails and corresponding limit mechanisms and the auxiliary adsorption of the suction nozzle, thereby ensuring the feasibility of using the rotational movement of the substrate handover mechanism 100 to compensate for the circumferential error of the chip loading.

[0088] In addition, during the lowering process of the adsorption base 24 , in order to prevent collision between the adsorption base 24 and the rotating base 10 , in this embodiment, a vertical buffer pad 724 is provided at the bottom of the groove 11 of the rotating base 10 to effectively protect the rotating base 10 .

[0089] In this embodiment, a flexible cable 75 is also provided. The suction channel 241 on the adsorption base 24 is connected to the vacuum air pipe. The vacuum air pipe and the cables connected to the electrical equipment on the adsorption base 24 are connected through the flexible cable 75. The flexible cable is a dedicated motion pipeline component, which is safe and reliable during the vertical lifting process and will not be damaged by friction.

[0090] Please refer to Figure 8 As shown, in this embodiment, based on the exposure stage system, a wafer handover method is also provided, which includes the following steps:

[0091] S1: Raise the adsorption component so that the adsorption component extends through the through hole on the wafer stage; the lifting and lowering method and adsorption method of the adsorption component are as described above.

[0092] S2: The adsorption component receives and adsorbs the wafer. Specifically, the wafer is placed on the adsorption component through a robot, and the adsorption component vacuum adsorbs the wafer.

[0093] S3: Lower the adsorption assembly so that the wafer is placed on the wafer stage; the vacuum on the wafer stage can be activated to adsorb the wafer on the wafer stage;

[0094] S4: Check whether the circumferential position error of the wafer meets the requirements; if it does, the wafer handover is completed; if it does not, the adsorption assembly is raised, the rotating seat rotates and drives the adsorption assembly to rotate to compensate for the circumferential position error of the wafer, and step S3 is re-executed; the circumferential position error of the wafer on the wafer stage can be detected by an alignment mechanism, and its detection method is existing technology and will not be described here. A corresponding compensation angle can be generated based on the circumferential position error value detected by the alignment mechanism, and then the rotating seat rotates the corresponding compensation angle to compensate for the position of the wafer. Specifically, the rotation angle of the rotating seat can be controlled by the cooperation of the circumferential grating scale and the rotation limit sensor.

[0095] Example 2

[0096] The difference between this embodiment and the first embodiment lies in the number of adsorption bases 24 and the vertical driving method. In this embodiment, a plurality of adsorption bases 24 are provided and matched with each adsorption rack. Each adsorption base 24 can be installed on the rotating base 10 to be lifted and lowered along the first direction Z, and each adsorption base 24 is respectively equipped with a vertical driving member for independent lifting and lowering drive. The vertical driving member is preferably a linear motor, and each adsorption rack can be driven to lift and lower separately. Then, the vertical position compensation during the handover of the wafer can be performed more flexibly, thereby meeting the adsorption requirements of the wafer with large warping, and ensuring the feasibility of the handover of the wafer with large warping.

[0097] Example 3

[0098] This embodiment differs from the first embodiment in the bearing type. Bearing 50 in this embodiment utilizes an air-floating hydrostatic bearing, a type of sliding bearing. Its structure and operating principle are similar to those of liquid sliding bearings, except that it uses gas as the lubricant. When external compressed gas enters the bearing gap through a throttle, it forms a lubricating gas film with a certain load-bearing capacity and rigidity. This film's lubricating support keeps the shaft levitated within the bearing. This air-floating hydrostatic bearing ensures high operating accuracy, effectively reduces sliding resistance, and mitigates vibration.

[0099] In summary, the substrate handover mechanism includes: a rotating seat 10, an adsorption assembly 20, a base 30 and a rotating drive member 40; the rotating seat 10 is mounted on the base 30 in a manner that it can rotate along its own central axis a, and the base 30 is used to be installed on the workbench of the exposure table system; the adsorption assembly 20 includes a suction nozzle 21, and the suction nozzle 21 is arranged on the rotating seat 10 for adsorbing the wafer; the rotating drive member 40 is arranged on the base 30 for driving the rotating seat 10 to rotate around its own central axis.

[0100] With such configuration, the substrate handover mechanism and the exposure system only need to adaptively drive the rotating seat 10 in the substrate handover mechanism to rotate when compensating for the circumferential position error of the wafer, and there is no need to drive the entire exposure system to rotate. On the one hand, it is conducive to simplifying the rotation structure to reduce the hardware cost or R&D cost required for compensating for the circumferential position error of the wafer, thereby improving the input-output ratio. On the other hand, it makes the overall size and mass of the entire rotation drive structure smaller, which is conducive to achieving higher rotation accuracy.

[0101] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0102] The above description is only a description of the preferred embodiments of the invention and does not limit the scope of the invention. Any changes and modifications made by ordinary technicians in the field of the invention based on the above disclosure shall fall within the scope of protection of the claims.

Claims

1. A substrate transfer mechanism, characterized in that: The substrate transfer mechanism is integrated with the wafer stage, and moves along with the wafer stage; the substrate transfer mechanism includes: a rotating seat, an adsorption assembly, a base, and a rotating drive member; The rotating seat is mounted on the base in a manner that it can rotate along its own central axis, and the base is used to be mounted on the workbench of the exposure table system; The adsorption assembly is arranged on the rotating seat for adsorbing the wafer, and the adsorption assembly is arranged to be raised and lowered relative to the wafer stage along the direction of the central axis of the rotating seat, and the adsorption assembly can be rotated relative to the wafer stage with the central axis of the rotating seat as the center. The wafer stage is used to place the wafer for exposure; The rotation driving member is arranged on the base and is used to drive the rotating base to rotate around its own central axis; The rotating drive member includes a first drive member and a second drive member, the first drive member is arranged on the base, and the second drive member is arranged on the rotating seat. The first drive member is used to apply a driving force to the second drive member in a non-contact manner, and the driving force causes the second drive member to move linearly along a set direction tangent to the rotation direction of the rotating seat, so that the rotating seat can be driven to achieve a smaller rotation angle through the small linear movement of the second drive member, thereby compensating for the circumferential position error of the chip.

2. The substrate transfer mechanism according to claim 1, wherein: The base has a circular installation cavity, and the rotating seat is coaxially installed in the installation cavity.

3. The substrate transfer mechanism according to claim 1, wherein: The adsorption component includes a suction nozzle, and the suction nozzle is used for adsorbing the wafer.

4. The substrate transfer mechanism according to claim 2, wherein: One end of the rotating seat is located in the installation cavity, and the other end of the rotating seat is provided with a groove, and the adsorption component is installed in the groove.

5. The substrate transfer mechanism according to claim 4, wherein: Along a direction perpendicular to the central axis of the rotating seat, the groove overlaps with a projection of the mounting cavity.

6. The substrate transfer mechanism according to claim 2, wherein: The substrate handover mechanism further includes a bearing, the outer ring of the bearing is fixedly matched with the inner wall of the installation cavity, and the inner ring of the bearing is fixedly matched with the outer peripheral surface of the rotating seat.

7. The substrate transfer mechanism according to claim 6, wherein: The substrate handover mechanism further includes an elastic member, which is used to provide a preload force along a radial direction for the inner ring of the bearing. The preload force causes the inner ring of the bearing to approach the outer ring of the bearing along the radial direction.

8. The substrate transfer mechanism according to claim 6, wherein: The substrate handover mechanism also includes a bearing stopper, the upper end of the mounting cavity has an annular mounting groove that expands radially, the outer ring of the bearing is conformally mounted in the annular mounting groove and abuts against the axial side wall of the annular mounting groove, and the bearing stopper is arranged on the base and presses the bearing axially into the annular mounting groove.

9. The substrate transfer mechanism according to claim 3, wherein: The suction end of the suction nozzle is located on a side away from the rotating base along a first direction. The suction nozzle is arranged on the rotating base in a manner that it can be raised and lowered along the first direction. The first direction is parallel to the central axis of the rotating base.

10. The substrate transfer mechanism according to claim 9, wherein: The substrate handover mechanism further includes a vertical limiting mechanism, and the vertical limiting mechanism is used to limit the lifting height of the suction nozzle.

11. The substrate transfer mechanism according to claim 3, wherein: The adsorption assembly also includes several adsorption racks, each of which includes a support plate on which a first air duct is provided. At least two suction nozzles are installed on one side of the support plate away from the base along the first direction, and the inner cavity of the suction nozzle is connected to the first air duct.

12. The substrate transfer mechanism according to claim 11, wherein: The adsorption rack further includes a suction column connected to the support plate, the suction column extending in a first direction, the support plate extending in a direction perpendicular to the first direction, a second air channel provided on the suction column, and the second air channel communicating with the first air channel.

13. The substrate transfer mechanism according to claim 11, wherein: The adsorption assembly also includes an adsorption base, each of the adsorption racks is arranged on the adsorption base, and the adsorption base is arranged on the rotating seat in a manner that it can be raised and lowered along a first direction to achieve synchronous lifting and lowering of each suction nozzle, and the adsorption ends of each suction nozzle are arranged in the same plane.

14. The substrate transfer mechanism according to claim 13, wherein: An air suction channel is provided on the adsorption base, and the air suction channel is communicated with the first air channel corresponding to each adsorption rack.

15. The substrate transfer mechanism according to claim 11, wherein: The adsorption assembly also includes multiple adsorption bases, each of which is matched with each adsorption rack one by one. Each of the adsorption bases can be installed on the rotating seat so as to be lifted and lowered along the first direction. Each of the adsorption bases is equipped with a vertical driving member for independent lifting and lowering drive.

16. The substrate transfer mechanism according to claim 1, wherein: The substrate handover mechanism further includes a rotation limiting mechanism, and the rotation limiting mechanism is used to limit the rotation angle of the rotating seat.

17. The substrate transfer mechanism according to claim 16, wherein: The rotation limiting mechanism includes a circumferential grating scale and a rotation limit sensor. The circumferential grating scale is arranged on the base to detect the angular displacement of the rotating seat. The rotation limit sensor is used to receive the angular displacement detected by the circumferential grating scale and to limit the rotation angle of the rotating seat.

18. An exposure system, characterized in that: The exposure system is equipped with the substrate transfer mechanism according to any one of claims 1 to 17.

19. The exposure system according to claim 18, wherein: The exposure system further includes the wafer stage, which is provided with a through hole for the adsorption component to pass through when it is lifted or lowered.

20. A wafer handover method based on the exposure system of claim 19, characterized in that: The following steps are involved: S1: Raise the adsorption assembly so that the adsorption assembly extends through the through hole on the wafer stage; S2: The adsorption component receives and adsorbs the wafer; S3: lowering the adsorption assembly so that the wafer is placed on the wafer stage; S4: Check whether the circumferential position error of the wafer meets the requirements; if so, the wafer handover is completed; If the requirements are not met, the adsorption assembly is raised, the rotating seat is rotated and drives the adsorption assembly to rotate to compensate for the circumferential position error of the wafer, and step S3 is executed again.

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