Alignment precision detection device and wafer detection system

Abstract

The invention provides an alignment precision detection device and a wafer detection system. The alignment precision detection device comprises a first direction moving part, a second direction moving part and a lens assembly, the first direction moving part can drive the lens assembly to move in the first direction, and the second direction moving part can drive the lens assembly to move in the second direction; the first direction is perpendicular to the second direction; the bearing piece comprises a transverse rod extending in the first direction; the first direction moving part comprises a moving block, and the moving block is arranged on the cross rod in a sleeving mode and can move along the cross rod; and the moving block is in air floatation fit with the cross rod through the air foot part. According to the alignment precision detection device and the wafer detection system provided by the invention, the problem that the movement stability and the positioning accuracy of the lens assembly driven by the movement assembly are poorer due to the fact that the movement state of the movement assembly of the existing alignment precision detection device is influenced by processing and mounting errors can be solved.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing equipment technology, and more specifically, to an alignment accuracy detection device and a wafer inspection system. Background Technology

[0002] Semiconductor technology, as the cornerstone of modern information society, plays an immeasurable role in driving technological progress and promoting economic development. In the semiconductor device manufacturing process, wafer bonding is a crucial step in achieving advanced packaging technologies such as 3D integration and heterogeneous integration, while wafer inspection equipment is the core equipment for ensuring bonding accuracy and improving device performance and yield. Precise wafer alignment can effectively reduce alignment errors after bonding, thereby improving the quality and consistency of the final product.

[0003] Although the upper and lower wafers are aligned before bonding, their relative positions may still shift slightly due to bonding pressure, temperature changes, and other possible external interference factors. Therefore, after bonding the upper and lower wafers, it is necessary to test the alignment accuracy of the bonded wafers to check whether they still maintain the expected alignment state. This allows for the rejection of non-compliant products, and the adjustment of the process in future batches based on the alignment accuracy test results. This continuously improves the bonding effect, reduces the defect rate, and increases production efficiency and economic benefits.

[0004] Existing alignment accuracy testing devices typically mount the lens assembly on a carrier, which supports and guides the lens assembly. During the alignment accuracy testing system's process of moving the lens assembly along the carrier and positioning it to the testing position via a motion component, the motion component and the carrier come into contact. However, the carrier usually has processing and installation errors, so the motion state of the motion component is affected by these errors. This results in poor stability of the lens assembly driven by the motion component, and the lens assembly cannot move accurately and be positioned to the predetermined position. Summary of the Invention

[0005] The main objective of this invention is to provide an alignment accuracy detection device and a wafer inspection system, which can solve the problem that the motion state of the motion components of existing alignment accuracy detection devices is affected by processing and installation errors, resulting in poor motion stability and positioning accuracy of the lens assembly driven by the motion components.

[0006] To achieve the above objectives, according to one aspect of the present invention, an alignment accuracy detection device is provided, comprising: a first direction movement part, a second direction movement part, and a lens assembly, wherein the first direction movement part is capable of driving the lens assembly to move along a first direction, and the second direction movement part is capable of driving the lens assembly to move along a second direction; the first direction and the second direction are perpendicular to each other; a support member, the support member including a crossbar extending along the first direction; the first direction movement part including: a moving block, the moving block being sleeved on the crossbar and capable of moving along the crossbar; and an air-support component, the moving block being air-supported to the crossbar via the air-support component.

[0007] Furthermore, the movable block includes a first plate located below the crossbar and a second plate located above the crossbar; the air supply component includes a first positive pressure part and a second positive pressure part, the first positive pressure part being disposed on the first plate or the crossbar; the second positive pressure part being disposed on the second plate or the crossbar.

[0008] Furthermore, the air-supported component also includes: a first negative pressure part, which is disposed on the first plate or crossbar; the first negative pressure part can generate negative pressure to attract and fix the crossbar and the first plate together; the air-supported component also includes a first air-floating pad and a first driving member connected by a drive, the first air-floating pad is disposed on one of the second plate and the crossbar, and the first driving member can drive the first air-floating pad to move, so as to provide the first air-floating pad with a force that can press against the other of the second plate and the crossbar.

[0009] Furthermore, the air-supported component also includes: a second negative pressure part, which is disposed on the second plate or crossbar; the second negative pressure part can generate negative pressure to attract and fix the crossbar and the second plate together; the air-supported component also includes a second air-floating pad and a second driving member connected by a drive, the second air-floating pad is disposed on one of the first plate and the crossbar, and the second driving member can drive the second air-floating pad to move, so as to provide the second air-floating pad with a force that can press against the other of the first plate and the crossbar.

[0010] Furthermore, the air foot component also includes: a third air cushion and a third driving member connected by a drive; the third air cushion is disposed on one of the second plate and the crossbar; the third driving member can drive the third air cushion to move, so as to provide the third air cushion with a force that can press against the other of the second plate and the crossbar; the air foot component also includes a fourth air cushion and a fourth driving member connected by a drive; the fourth air cushion is disposed on one of the first plate and the crossbar; the fourth driving member can drive the fourth air cushion to move, so as to provide the fourth air cushion with a force that can press against the other of the first plate and the crossbar.

[0011] Furthermore, the movable block includes a first side plate and a second side plate located on both sides of the crossbar. A second directional moving part is provided on the outer side of the first side plate, and a counterweight is provided on the outer side of the second side plate.

[0012] Furthermore, at least one of the first side plate and the second side plate includes an inner side plate and an outer side plate, which are connected by a flexible hinge.

[0013] Furthermore, along the third direction, the side of the first side plate facing the crossbar is the first inner side, and the side of the second side plate facing the crossbar is the second inner side; the first direction, the second direction, and the third direction are perpendicular to each other; the air supply component also includes a first air float and a second air float, the first air float is disposed on the first inner side; the second air float is disposed on the second inner side.

[0014] Furthermore, the air-supported component also includes: a first adjusting member and a second adjusting member, wherein the first adjusting member is driven to connect to the first air float block, and the second adjusting member is driven to connect to the second air float block; the first adjusting member is used to adjust the gap between the first air float block and the crossbar, and the second adjusting member is used to adjust the gap between the second air float block and the crossbar.

[0015] Furthermore, the alignment accuracy detection device also includes a worktable and a third-direction motion unit. The support member is set on the worktable, and the third-direction motion unit can drive the support member to slide along the third direction. A first guide rail extending along the third direction is provided on the worktable. The support member includes columns set at both ends of the crossbar. The columns are slidably installed on the first guide rail. The third-direction motion unit includes a fifth driving member, which can drive the columns to move along the first guide rail.

[0016] Furthermore, the precision detection device also includes a sixth driving element, which can drive the column to move along the first direction; the two sixth driving elements differentially drive the column to drive the bearing to move along the RZ axis.

[0017] Furthermore, a connector is provided at the bottom of the column, which covers the first guide rail. The connector includes a third plate located above the first guide rail and a third side plate and a fourth side plate located on both sides of the first guide rail. Along the first direction, the side of the third side plate facing the first guide rail is the third inner side, on which a fifth air cushion is provided. The side of the fourth side plate facing the first guide rail is the fourth inner side, on which a sixth air cushion is provided. The fifth and sixth air cushions can provide a force to press against the first guide rail. The sixth driving component includes a second stator and a second mover. The second stator is provided on the column, and the second mover is provided on the connector. The second stator and the second mover slide together to drive the column to move along the first direction.

[0018] Furthermore, a second guide rail extending along a third direction is provided on the workbench, and a balance block is installed on the second guide rail. The balance block can slide along the second guide rail. The fifth driving component includes a third stator and a third mover. The third stator is set on the column, and the third mover is set on the balance block. The third stator and the third mover slide in cooperation to drive the column and the balance block to slide relative to each other along a third direction.

[0019] Furthermore, the third-direction motion unit also includes a seventh driving member, which includes a fourth stator and a fourth mover. The fourth stator is disposed on the worktable, and the fourth mover is disposed on the balance block. The fourth stator and the fourth mover are slidably engaged to drive the balance block to slide along the third direction. According to another aspect of the present invention, a wafer inspection system is also provided, comprising: a worktable; an upper wafer motion system including an upper wafer carrier for carrying the upper wafer; a lower wafer motion system including a lower wafer carrier for carrying the lower wafer; further comprising: the aforementioned alignment accuracy detection device for performing wafer verification detection after bonding; and: a wafer alignment detection device for performing wafer alignment detection before bonding.

[0020] Applying the technical solution of this invention, the first direction motion unit provides the lens assembly with a degree of freedom along the first direction, and the second direction motion unit provides the lens assembly with a degree of freedom along the second direction. The first and second directions are perpendicular to each other, allowing the first and second direction motion units to cooperate and drive the lens assembly to move precisely in two directions in the X, Y, and Z three-dimensional coordinate system to locate different detection positions. The lens assembly is responsible for capturing images of the wafer for alignment accuracy analysis and detection. The support member provides a stable foundation, while the crossbar serves as a guide structure for the first direction motion unit, ensuring smooth and linear movement of the lens assembly along the first direction, reducing wobbling and deviation during lens assembly movement, and improving the stability and positioning accuracy of the lens assembly. The moving block carries the lens assembly and drives it to move along the crossbar. The air-supported component can form an air-float gap between the moving block and the crossbar, thereby suspending the moving block relative to the crossbar.

[0021] The alignment accuracy detection device provided by this invention, through the cooperation of the air foot component and the moving block, enables the moving block to suspend relative to the crossbar, avoiding contact and friction between the moving block and the crossbar during movement, and preventing vibration and displacement caused by the crossbar's processing accuracy and surface quality. This significantly improves the stability of the lens assembly's movement, ensures the precise positioning of the lens assembly during wafer inspection, and improves the detection accuracy. Attached Figure Description

[0022] The accompanying drawings, which form part of this specification, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0023] Figure 1 A schematic diagram of the overall structure of the alignment accuracy detection device according to an embodiment of the present invention is shown, showing the first angle of the device.

[0024] Figure 2 A top view of an alignment accuracy detection device according to an embodiment of the present invention is shown;

[0025] Figure 3 A schematic diagram of the overall structure of the second angle of the alignment accuracy detection device according to an embodiment of the present invention is shown.

[0026] Figure 4 A schematic diagram of the overall structure of the third-direction motion part of the alignment accuracy detection device according to an embodiment of the present invention is shown.

[0027] Figure 5 A schematic diagram of the overall structure of the second angle of the third-direction motion part of the alignment accuracy detection device according to an embodiment of the present invention is shown.

[0028] Figure 6 This shows a front view of the third-direction moving part of the alignment accuracy detection device according to an embodiment of the present invention;

[0029] Figure 7 A schematic diagram of the overall structure of the air foot component of the alignment accuracy detection device according to an embodiment of the present invention is shown at the first angle.

[0030] Figure 8 A cross-sectional view of the air foot component of the alignment accuracy detection device according to an embodiment of the present invention is shown;

[0031] Figure 9 An exploded view of the air foot component of the alignment accuracy detection device according to an embodiment of the present invention is shown;

[0032] Figure 10 A schematic diagram of the overall structure of the second angle of the air foot component of the alignment accuracy detection device according to an embodiment of the present invention is shown;

[0033] Figure 11 A front view of the air foot component of the alignment accuracy detection device according to an embodiment of the present invention is shown;

[0034] Figure 12 A cross-sectional view of the air foot component of the alignment accuracy detection device according to an embodiment of the present invention is shown;

[0035] Figure 13 A schematic diagram of the overall structure of the inner and outer side plates of the alignment accuracy detection device according to an embodiment of the present invention is shown.

[0036] Figure 14 An exploded view of the inner and outer plates of the alignment accuracy detection device according to an embodiment of the present invention is shown;

[0037] Figure 15 A top view of the inner and outer plates of the alignment accuracy detection device according to an embodiment of the present invention is shown;

[0038] Figure 16 A front view of the inner plate of the alignment accuracy detection device according to an embodiment of the present invention is shown;

[0039] Figure 17 A cross-sectional view of the negative pressure channel of the alignment accuracy detection device according to an embodiment of the present invention is shown;

[0040] Figure 18 A cross-sectional view of the positive pressure channel of the alignment accuracy detection device according to an embodiment of the present invention is shown;

[0041] Figure 19 A cross-sectional view of the air foot component of an alignment accuracy detection device according to another embodiment of the present invention is shown; and

[0042] Figure 20 A schematic diagram of the overall structure of the air foot component of the alignment accuracy detection device according to another embodiment of the present invention is shown.

[0043] The above figures include the following reference numerals:

[0044] 1. Worktable; 11. First guide rail; 12. Second guide rail; 2. Upper wafer motion system; 21. Upper wafer carrier; 3. Lower wafer motion system; 31. Lower wafer carrier; 43. Crossbar; 44. Column; 52. Lens assembly; 58. Moving block; 581. First plate; 5821. First side plate; 5822. Second side plate; 583. Second plate; 584. Inner side plate; 585. Outer side plate; 586. Flexible hinge; 5871. First air float; 5872. First air float block; 5873. Second air float block; 588. Counterweight; 589. First negative pressure groove; 59. Second direction motion part; 61. Air film thickness sensor; 62. Air film thickness adjustment part; 7. Bearing component; 8. Adapter component; 81. Third plate; 82. Third side plate; 8 21. Fifth air-float; 83. Fourth side plate; 831. Sixth air-float; 9. Balance block; 131. Mounting channel; 132. Piezoelectric ceramic unit; 133. Piezoelectric stacking carrier plate; 141. Second negative pressure groove; 142. Negative pressure channel; 143. Negative pressure vent; 144. Vacuum valve; 145. Positive pressure channel; 146. Positive pressure vent; 147. Positive pressure valve; 151. First grating ruler; 152. Second grating ruler; 153. Third grating ruler; 16. Linear motor; 161. First stator; 162. First mover; 17. Fifth drive unit; 171. Third stator; 172. Third mover; 18. Sixth drive unit; 181. Second stator; 182. Second mover; 19. Seventh drive unit; 191. Fourth stator; 192. Fourth mover. Detailed Implementation

[0045] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0046] See also Figures 1 to 20 As shown, the present invention provides an alignment accuracy detection device, which includes a first direction movement part 59, a second direction movement part 59, a support member 7, and a lens assembly 52. ​​The first direction movement part 59 can drive the lens assembly 52 to move along a first direction, and the second direction movement part 59 can drive the lens assembly 52 to move along a second direction; the first and second directions are perpendicular to each other. The support member 7 includes a crossbar 43 extending along the first direction. The first direction movement part includes a moving block 58 and an air-supported component, wherein the moving block 58 is sleeved on the crossbar 43 and can move along the crossbar 43; the moving block 58 is air-supported to the crossbar 43 via the air-supported component.

[0047] In the above technical solution, the first direction motion unit provides the lens assembly 52 with a degree of freedom along the first direction, and the second direction motion unit 59 provides the lens assembly 52 with a degree of freedom along the second direction. The first and second directions are perpendicular to each other, allowing the first and second direction motion units 59 to work together to drive the lens assembly 52 to move precisely in two directions in the X, Y, and Z three-dimensional coordinate system to locate different detection positions. The X-axis corresponds to the first direction, the Y-axis corresponds to the third direction, and the Z-axis corresponds to the second direction. The lens assembly 52 is responsible for capturing images of the wafer for alignment accuracy analysis and detection. The support member 7 provides a stable foundation, while the crossbar 43 serves as a guide structure for the first direction motion unit, ensuring smooth and linear movement of the lens assembly 52 along the first direction, reducing wobbling and deviation during movement, and improving the stability and positioning accuracy of the lens assembly 52. The movable block 58 is used to support the lens assembly 52 and drive the lens assembly 52 to move along the crossbar 43. The air-supported component can form an air-float gap between the movable block 58 and the crossbar 43, thereby making the movable block 58 suspend relative to the crossbar 43.

[0048] The alignment accuracy detection device provided by the present invention enables the moving block 58 to suspend relative to the crossbar 43 through the cooperation of the air foot component and the moving block 58. This avoids the moving block 58 from contacting and rubbing against the crossbar 43 during movement and from vibrating and shifting due to the influence of the crossbar 43's processing accuracy and surface quality. As a result, it significantly improves the stability of the lens assembly 52's movement, ensures the precise positioning of the lens assembly during wafer inspection, and improves the detection accuracy.

[0049] In one embodiment of the present invention, the moving block 58 includes a first plate 581 located below the crossbar 43 and a second plate 583 located above the crossbar 43; the air supply component includes a first positive pressure part and a second positive pressure part, the first positive pressure part being disposed on the first plate 581 or the crossbar 43; the second positive pressure part being disposed on the second plate 583 or the crossbar 43.

[0050] In the above technical solution, the first plate 581 is located below the crossbar 43 and is used to support the first positive pressure part. The first positive pressure part is disposed on the first plate 581 or the crossbar 43, mainly to form an air-floating gap between the first plate 581 and the crossbar 43, thereby suspending the first plate 581 relative to the crossbar 43. The second plate 583 is disposed above the crossbar 43 and is used to support the second positive pressure part. The second positive pressure part is disposed on the second plate 583 or the crossbar 43, mainly to form an air-floating gap between the second plate 583 and the crossbar 43, thereby suspending the second plate 583 relative to the crossbar 43. Through the combined action of the first and second positive pressure parts, the moving block 58 has an air-floating gap with the crossbar 43 in the vertical direction, ensuring that the moving block 58 will not contact the top surface or the bottom surface of the crossbar 43 during its movement along the crossbar 43, ensuring that the moving block 58 is suspended relative to the crossbar 43 and avoiding the crossbar 43 affecting the movement of the moving block 58.

[0051] In one embodiment of the present invention, the air-supported component further includes: a first negative pressure part, a first air-floating pad 5871, and a first driving member. The first negative pressure part is disposed on the first plate 581 or the crossbar 43, and can generate negative pressure to adsorb and fix the crossbar 43 and the first plate 581 together. The first air-floating pad 5871 and the first driving member are drivenly connected. The first air-floating pad 5871 is disposed on one of the second plate 583 and the crossbar 43, and the first driving member can drive the first air-floating pad 5871 to move, thereby providing the first air-floating pad 5871 with a force capable of pressing against the other of the second plate 583 and the crossbar 43.

[0052] In the above technical solution, the first negative pressure part is used to draw air to form a negative pressure. The first negative pressure part is set on the first plate 581 or the crossbar 43, and a negative pressure area is formed between the crossbar 43 and the first plate 581, so that the first plate 581 is adsorbed and fixed on the crossbar 43. The first air float 5871 can be set on one of the second plate 583 and the crossbar 43. The first pre-tightening member usually includes components such as a hydraulic cylinder, a pneumatic cylinder or an electric push rod. When the first air float 5871 is set on the second plate 583, the first pre-tightening member drives the first air float 5871 to rise, so that the first air float 5871 presses against the crossbar 43, thereby ensuring that the moving block 58 is fixed relative to the crossbar 43. At this time, the moving block 58 is in a locked state. By driving the first air float 5871 to fall through the first pre-tightening member, the first air float 5871 is disengaged from the crossbar 43, thus completing the switch of the moving block 58 from the locked state to the unlocked state. When the first air cushion 5871 is set on the side of the crossbar 43 facing the second plate 583, the first pretensioner can drive the first air cushion 5871 to extend or retract towards the second plate 583, thereby realizing the switching of the moving block 58 between the locked state and the unlocked state. The specific process is the same as when the first air cushion 5871 is set on the second plate 583, and will not be described again.

[0053] By cooperating with the first negative pressure part and the first air float 5871, the moving block 58 is adsorbed and fixed on one side of the crossbar 43, and the moving block 58 is pressed and fixed on the other side, which further improves the strength and reliability of the moving block 58 fixation, ensuring that the moving block 58 and its mounted lens assembly 52 are completely fixed on the crossbar 43 and are not affected by any slight vibration, thereby minimizing the static jitter generated by the lens assembly 52 and ensuring the accuracy of wafer alignment and detection.

[0054] In one embodiment of the present invention, a first negative pressure groove 589 is provided on the first plate 581 corresponding to the first negative pressure part, and the first negative pressure part is configured to be able to adsorb and fix the first plate 581 to the bottom surface of the crossbar 43 through the first negative pressure groove 589.

[0055] In the above technical solution, the first negative pressure section is used to extract air to form negative pressure, and the first negative pressure groove 589 is disposed on the surface of the first plate 581 in contact with the crossbar 43, defining the area where negative pressure is formed. During negative pressure adsorption, the first negative pressure section cooperates with the first negative pressure groove 589, and the first negative pressure section extracts air from the first negative pressure groove 589, thereby forming a vacuum area in the first negative pressure groove 589, so that the first plate 581 is adsorbed and fixed on the bottom surface of the crossbar 43, thereby fixing the moving block 58 and avoiding the problem of sliding or shifting of the moving block 58 during the detection of the lens assembly 52, which would lead to a decrease in detection accuracy. This minimizes the static jitter generated by the lens assembly 52 and ensures the accuracy of wafer alignment detection.

[0056] In one embodiment of the present invention, the air-supported component further includes: a second negative pressure part, a second air-floating pad, and a second driving member. The second negative pressure part is disposed on the second plate 583 or the crossbar 43, and can generate negative pressure to adsorb and fix the crossbar 43 and the second plate 583 together. The second air-floating pad and the second driving member are drivenly connected. The second air-floating pad is disposed on one of the first plate 581 and the crossbar 43, and the second driving member can drive the second air-floating pad to move, thereby providing the second air-floating pad with a force capable of pressing against the other of the first plate 581 and the crossbar 43.

[0057] In the above technical solution, the second negative pressure part is used to draw air to form a negative pressure. By setting the second negative pressure part on the second plate 583 or the crossbar 43, a negative pressure area can be formed between the second plate 583 and the crossbar 43, thereby allowing the second plate 583 to be adsorbed and fixed onto the crossbar 43. The second air float can be set on one of the first plate 581 or the crossbar 43. The first pre-tightening member typically includes components such as a hydraulic cylinder, a pneumatic cylinder, or an electric push rod. When the second air float is set on the first plate 581, the first pre-tightening member drives the second air float to rise, causing the second air float to press against the crossbar 43, thereby ensuring that the moving block 58 is fixed relative to the crossbar 43. At this time, the moving block 58 is in a locked state. By driving the second air float to fall through the first pre-tightening member, the second air float is disengaged from the crossbar 43, thus completing the switch of the moving block 58 from the locked state to the unlocked state. When the second air cushion is set on the side of the crossbar 43 facing the first plate 581, the first pre-tightening member can drive the second air cushion to extend or retract toward the first plate 581, thereby realizing the switching of the moving block 58 between the locked state and the unlocked state. The specific process is the same as when the second air cushion is set on the first plate 581, and will not be described again.

[0058] By cooperating with the second negative pressure part and the second air float, the moving block 58 is adsorbed and fixed on one side of the crossbar 43, and the moving block 58 is pressed and fixed on the other side, which further improves the strength and reliability of the moving block 58 fixation, ensuring that the moving block 58 and its mounted lens assembly 52 are completely fixed on the crossbar 43 and are not affected by any slight vibration, thereby minimizing the static jitter generated by the lens assembly 52 and ensuring the accuracy of wafer alignment and inspection.

[0059] In one embodiment of the present invention, the air foot component further includes: a third air cushion, a third driving member, a fourth air cushion, and a fourth driving member. The third air cushion and the third driving member are drivenly connected. The third air cushion is disposed on one of the second plate 583 and the crossbar 43. The third driving member can drive the third air cushion to move, thereby providing the third air cushion with a force capable of pressing against the other of the second plate 583 and the crossbar 43. The fourth air cushion and the fourth driving member are drivenly connected. The fourth air cushion is disposed on one of the first plate 581 and the crossbar 43. The fourth driving member can drive the fourth air cushion to move, thereby providing the fourth air cushion with a force capable of pressing against the other of the first plate 581 and the crossbar 43.

[0060] In the above technical solution, the third air float is disposed on one of the second plate 583 and the crossbar 43. The third driving component typically includes components such as a hydraulic cylinder, a pneumatic cylinder, or an electric push rod. The third driving component can drive the third air float to move up and down, thereby pressing the third air float against the other of the second plate 583 and the crossbar 43. The fourth air float is disposed on one of the first plate 581 and the crossbar 43. The fourth driving component includes components such as a hydraulic cylinder, a pneumatic cylinder, or an electric push rod. The fourth driving component can drive the third air float to move up and down, thereby pressing the fourth air float against the other of the first plate 581 and the crossbar 43. By cooperating with the third and fourth air floats, the moving block 58 can be pressed and fixed from both sides of the crossbar 43, improving the strength and reliability of the moving block 58 fixation. This ensures that the moving block 58 and its mounted lens assembly 52 are completely fixed on the crossbar 43, unaffected by any minor vibrations, thereby minimizing the static jitter generated by the lens assembly 52 and ensuring the accuracy of wafer alignment and inspection.

[0061] In one embodiment of the present invention, the surfaces of the third and fourth air floats are provided with air holes. When the moving block 58 is in an active state, air can be pumped into the third and fourth air floats by an air source device such as an air pump. The gas is blown out through the air holes on the surface of the air floats, thereby forming an active air gap by relatively suspending the moving block 58 and the crossbar 43. This ensures that the moving block 58 moves along the crossbar 43 without rigid contact and friction with the crossbar 43, reducing friction. At the same time, it avoids the movement of the moving block 58 along the crossbar 43 being affected by the processing error and surface quality of the crossbar 43, which would cause movement errors in the moving block 58 and its mounted lens assembly 52.

[0062] In one embodiment of the present invention, the movable block 58 includes a first side plate 5821 and a second side plate 5822 located on both sides of the crossbar 43. A second direction movement part 59 is provided on the outer side of the first side plate 5821, and a counterweight block 588 is provided on the outer side of the second side plate 5822.

[0063] In the above technical solution, the first side plate 5821 and the second side plate 5822, together with the second plate 583 and the first plate 581, constitute the moving block 58. The first side plate 5821 provides a mounting base for the second-direction moving part 59, and the second side plate 5822 provides a mounting base for the counterweight 588. The second-direction moving part 59 is responsible for driving the lens assembly 52 to move along the second direction to adapt to different wafer heights and alignment mark detection requirements. The counterweight 588 is installed on the outside of the second side plate 5822. Its main purpose is to balance the weight of the second-direction moving part 59, prevent the moving block 58 from tilting or shaking due to instability of the center of gravity during movement, and ensure the stability and accuracy of the movement of the lens assembly 52.

[0064] In one embodiment of the present invention, at least one of the first side plate 5821 and the second side plate 5822 includes an inner side plate 584 and an outer side plate 585, which are connected by a flexible hinge 586.

[0065] In the above technical solution, the movable block 58 includes a first plate 581, a second plate 583, and two side plates, namely a first side plate 5821 and a second side plate 5822. One of the first side plates 5821 and 5822 is jointly formed by an inner side plate 584 near the crossbar 43 and an outer side plate 585 outside the inner side plate 584, or both the first side plate 5821 and 5822 are formed by an inner side plate 584 and an outer side plate 585. The inner side plate 584 and the outer side plate 585 are connected by a flexible hinge 586, which allows the inner side plate 584 to be tilted independently of the outer side plate 585. This ensures that the inner side plate 584 is always parallel to the side of the crossbar 43, thereby improving the uniformity of the air film thickness between the side plate with the flexible hinge 586 and the crossbar 43, and further improving the stability and accuracy of the air buoyancy movement of the movable block 58.

[0066] In one embodiment of the present invention, at least one of the first side plate 5821 and the second side plate 5822 is provided with an air film thickness adjustment assembly. The air film thickness adjustment assembly includes an air film thickness sensor 61 and an air film thickness adjustment part 62. The air film thickness sensor 61 can monitor the air film thickness, and the air film thickness adjustment part 62 is disposed between the inner side plate 584 and the outer side plate 585 and can adjust the air gap distance between the inner side plate 584 and the crossbar 43.

[0067] In the above technical solution, the movable block 58 includes a first plate 581, a second plate 583 and two side plates, namely a first side plate 5821 and a second side plate 5822. An air film thickness adjustment component is provided on one of the first side plate 5821 and the second side plate 5822, or an air film thickness adjustment component is provided on both the first side plate 5821 and the second side plate 5822. The air film thickness adjustment assembly is used to adjust the air film thickness between the inner side plate 584 and the crossbar 43. The air film thickness adjustment assembly includes an air film thickness sensor 61 and an air film thickness adjustment part 62. The air film thickness sensor 61 is disposed on the side plate where the air film thickness adjustment assembly is located. Its detection end face is flush with the surface of the inner side plate 584 facing the crossbar 43. When an air film is formed between the inner side plate 584 and the side of the crossbar 43, so that there is an air gap between the inner side plate 584 and the crossbar 43, the detection end face of the air film thickness sensor 61 detects the distance between the detection end face and the surface of the crossbar 43, which is the air film thickness between the inner side plate 584 and the crossbar 43. The air film thickness adjustment unit 62 typically includes components such as piezoelectric ceramics. It can drive the inner side plate 584 to move closer to or further away from the crossbar 43 based on the air film thickness monitored by the air film thickness sensor 61, thereby adjusting the distance between the inner side plate 584 and the crossbar 43. This ensures that the inner side plate 584 remains parallel to the crossbar 43, thus achieving the effect of adjusting the air film thickness and ensuring that a uniform air film thickness is maintained between the side plate and the crossbar 43. In one embodiment of the present invention, a plurality of piezoelectric ceramic unit arrays are arranged between the inner side plate 584 and the outer side plate 585 to form an air film thickness adjustment array. Specifically, the outer side plate 585 has a plurality of mounting channels 131 spaced apart on its surface facing the inner side plate 584. A plurality of piezoelectric ceramic units 132 are spaced apart on a piezoelectric stacking carrier plate 133. The piezoelectric ceramic units 132 are respectively installed into the corresponding mounting channels 131 through the piezoelectric stacking carrier plate 133, thereby forming the air film thickness adjustment array.

[0068] In the above technical solution, by arranging multiple piezoelectric ceramic units 132 in an array between the inner side plate 584 and the outer side plate 585 to form an air film thickness adjustment array, it is possible to individually adjust the specific points where the air film thickness between the side plate and the crossbar 43 is abnormal based on the air film thickness data monitored by multiple air film thickness sensors 61. This drives the inner side plate 584 to move closer to or further away from the crossbar 43 at the abnormal point, ensuring that the inner side plate 584 always remains parallel to the crossbar 43, so that the air film thickness between the side plate and the crossbar 43 can always be maintained uniformly.

[0069] In one embodiment of the present invention, a plurality of air film thickness sensors 61 are arranged at intervals on the side plate, with the detection end face of the air film thickness sensors 61 facing the crossbar 43 and flush with the surface of the inner side plate 584. By setting a plurality of air film thickness sensors 61 and arranging them at intervals on the side plate, the air film thickness between different positions of the side plate and the crossbar 43 can be monitored, thereby increasing the number of sampling points and data volume of the air film thickness between the side plate and the crossbar 43, significantly improving the accuracy of air film thickness monitoring. Based on this, in conjunction with the piezoelectric ceramic unit array of the air film thickness adjustment unit 62, it is possible to adjust the specific points where the air film thickness between the side plate and the crossbar 43 is abnormal, thereby achieving the effect of fine air film thickness adjustment, further improving the uniformity of air film thickness, ensuring that the moving block 58 can perform stable and accurate air buoyancy movement, thereby improving the stability and accuracy of the movement of the lens assembly 52.

[0070] In one embodiment of the present invention, a second negative pressure groove 141 is provided on the surface of the inner side plate 584 facing the crossbar 43, a negative pressure channel 142 is provided in the inner side plate 584, a negative pressure air hole 143 is provided in the second negative pressure groove 141, and the second negative pressure groove 141 is connected to the negative pressure channel 142 through the negative pressure air hole 143. A vacuum valve 144 is also provided on the inner side plate 584, and the vacuum valve 144 is connected to the negative pressure channel 142 and the vacuum pump.

[0071] In the above technical solution, the second negative pressure groove 141 is used to form a negative pressure area. The negative pressure vent 143 and the negative pressure channel 142 are both used to connect the vacuum pump and the negative pressure area. The vacuum valve 144 ensures that air can be discharged from the negative pressure channel 142, while preventing external air from entering the negative pressure channel 142 and disrupting the negative pressure environment in the second negative pressure groove 141. By forming a negative pressure in the second negative pressure groove 141, the inner side plate 584 can be adsorbed and fixed on the crossbar 43, thus fixing the moving block 58. This prevents the moving block 58 from sliding or shifting during the inspection of the lens assembly 52, which could lead to a decrease in inspection accuracy. This minimizes the static vibration generated by the lens assembly 52 and ensures the accuracy of wafer alignment inspection.

[0072] In one embodiment of the present invention, a positive pressure channel 145 is provided in the inner side plate 584, and a positive pressure air hole 146 is opened on the surface of the inner side plate 584 facing the crossbar 43. The positive pressure air hole 146 is connected to the positive pressure channel 145. A positive pressure valve 147 is also provided on the inner side plate 584, and the positive pressure valve 147 is connected to the positive pressure channel 145 and the air pump.

[0073] In the above technical solution, the air pump pumps gas into the positive pressure channel 145 through the positive pressure valve 147. The gas enters the gap between the inner side plate 584 and the crossbar 43 through the positive pressure air hole 146 and the positive pressure channel 145. An air film is formed in the gap, so that the inner side plate 584 floats relative to the crossbar 43. This ensures that the inner side plate 584 will not have rigid contact and friction with the crossbar 43 when the moving block 58 moves along the crossbar 43, reducing the friction force. At the same time, it avoids the movement of the moving block 58 along the crossbar 43 from being affected by the processing error and surface quality of the crossbar 43, which would cause movement error of the moving block 58 and its mounted lens assembly 52.

[0074] In one embodiment of the present invention, along a third direction, the side of the first side plate 5821 facing the crossbar 43 is the first inner side, and the side of the second side plate 5822 facing the crossbar 43 is the second inner side; the first direction, the second direction, and the third direction are perpendicular to each other; the air supply component also includes a first air flotation block 5872 and a second air flotation block 5873, the first air flotation block 5872 is disposed on the first inner side; the second air flotation block 5873 is disposed on the second inner side.

[0075] In the above technical solution, an air source device such as an air pump can blow air into the gap between the first inner side and the crossbar 43 through the first air float 5872, thereby forming an air float gap. At the same time, the air source device such as an air pump can also blow air into the gap between the second inner side and the crossbar 43 through the second air float 5873, thereby forming an air float gap. By cooperating with the first air float 5872 and the second air float 5873, air float gaps can be formed on both sides of the crossbar 43 in the third direction at the same time. This prevents the two inner sides of the moving block 58 in the third direction from contacting the crossbar 43 when the moving block 58 moves along the crossbar 43, reducing friction. At the same time, it avoids the moving block 58 from being affected by the processing error and surface quality of the crossbar 43, which would cause errors in the movement and positioning of the moving block 58 and the lens assembly 52 it is mounted on.

[0076] In addition, a hydraulic cylinder, pneumatic cylinder, or electric push rod can drive the first air float 5872 and the second air float 5873 to move up and down along a third direction, so that the first air float 5872 and the second air float 5873 simultaneously clamp the crossbar 43 on both sides along the third direction, thereby ensuring the reliable fixation of the moving block 58 and its mounted lens assembly 52 on the crossbar 43, minimizing the static vibration caused by the lens assembly 52 being subjected to external forces, and thus ensuring the accuracy of wafer alignment and inspection.

[0077] In one embodiment of the present invention, the first side plate 5821 includes an inner side plate 584 and an outer side plate 585, wherein the side of the inner side plate 584 facing the crossbar 43 is the first inner side surface, the inner side plate 584 and the outer side plate 585 are connected by a flexible hinge 586, and the first air flotation block 5872 is disposed on the first inner side surface.

[0078] In the above embodiment, an air source device such as an air pump can blow air into the gap between the first inner side and the crossbar 43 through the first air float 5872, thereby forming an air float gap. At the same time, the inner side plate 584 and the outer side plate 585 are connected by a flexible hinge 586, so that the inner side plate 584 can be tilted independently of the outer side plate 585 to ensure that the inner side plate 584 is always parallel to the side of the crossbar 43. This improves the uniformity of the air float gap formed by the first air float 5872 between the inner side plate 584 and the crossbar 43, and further improves the stability and accuracy of the air float movement of the moving block 58.

[0079] In one embodiment of the present invention, the second side plate 5822 includes an inner side plate 584 and an outer side plate 585, wherein the side of the inner side plate 584 facing the crossbar 43 is the second inner side surface, the inner side plate 584 and the outer side plate 585 are connected by a flexible hinge 586, and the second air flotation block 5873 is disposed on the second inner side surface.

[0080] In the above embodiment, an air source device such as an air pump can blow air into the gap between the second inner side and the crossbar 43 through the second air float 5873, thereby forming an air float gap. At the same time, the inner side plate 584 and the outer side plate 585 of the second side plate 5822 are connected by a flexible hinge 586, so that the inner side plate 584 can be adjusted independently of the outer side plate 585 to ensure that the inner side plate 584 is always parallel to the side of the crossbar 43. This improves the uniformity of the air float gap formed by the second air float 5873 between the inner side plate 584 and the crossbar 43, and further improves the stability and accuracy of the air float movement of the moving block 58.

[0081] In one embodiment of the present invention, the first positive pressure part, the second positive pressure part, the first air flotation block and the second air flotation block cooperate to enable the moving block 58 to be air-suspended on the crossbar 43.

[0082] In the above technical solution, a first positive pressure part, a second positive pressure part, a first air buoyancy block, and a second air buoyancy block are simultaneously provided around the crossbar 43. The first positive pressure part is provided on the first plate 581 or the crossbar 43 and can form an air buoyancy gap between the first plate 581 and the crossbar 43. The second positive pressure part is provided on the second plate 583 or the crossbar 43 and can form an air buoyancy gap between the second plate 583 and the crossbar 43. The first air buoyancy block 5872 forms an air buoyancy gap between its first inner side and the crossbar 43. The second air buoyancy block 5873 forms an air buoyancy gap between its first inner side and the crossbar 43. An air-floating gap is formed between the inner side and the crossbar 43. Through the cooperation of the first positive pressure part, the second positive pressure part, the first air-floating block and the second air-floating block, an air-floating gap can be formed around the crossbar 43, so that the moving block 58 is completely air-suspended on the crossbar 43 and will not come into contact with the top, bottom and side surfaces of the crossbar 43. This further avoids the problem of errors in the movement and positioning of the moving block 58 and its mounted lens assembly 52 caused by the processing error and surface quality of the crossbar 43 during the movement of the moving block 58 along the crossbar 43.

[0083] In one embodiment of the present invention, the air-supported component further includes: a first adjusting member and a second adjusting member. The first adjusting member is drivenly connected to the first air-float block and is used to adjust the gap between the first air-float block and the crossbar 43; the second adjusting member is drivenly connected to the second air-float block and is used to adjust the gap between the second air-float block and the crossbar 43.

[0084] In the above technical solution, at least one side plate of the movable block 58 is provided with an adjusting component, which typically includes a screw, spring, or cylinder. The first adjusting component is drivenly connected to the first air float. When the gap between the first air float and the crossbar 43 is too large, the positive pressure generated by the first air float blowing air into the gap cannot make the movable block 58 fully float relative to the crossbar 43. At this time, by pushing the first air float closer to the crossbar 43 through the first adjusting component, the gap between the first air float and the crossbar 43 is reduced, thus enabling the gap between the first air float and the crossbar 43 to generate sufficient positive pressure, ensuring that the movable block 58 is fully and stably floated relative to the crossbar 43. The interaction relationship and effect between the second adjusting component and the second air float are the same as those between the first adjusting component and the first air float, and will not be described again here. By setting the first adjusting component and the second adjusting component, a suitable gap can be maintained between the air float and the crossbar 43, thereby ensuring that there is sufficient positive pressure between the air float and the crossbar 43, so that the movable block 58 is fully and stably floated relative to the crossbar 43.

[0085] In one embodiment of the present invention, the alignment accuracy detection device further includes a worktable 1 and a third-direction motion part. A support member 7 is disposed on the worktable 1, and the third-direction motion part can drive the support member 7 to slide along the third direction. A first guide rail 11 extending along the third direction is disposed on the worktable 1. The support member 7 includes columns 44 disposed at both ends of the crossbar. The columns 44 are slidably mounted on the first guide rail 11. The third-direction motion part includes a fifth driving member 17, which can drive the columns 44 to move along the first guide rail 11.

[0086] In the above technical solution, the worktable 1 provides a reliable mounting base for components such as the third-direction motion unit and the carrier 7. The carrier 7 is mounted on the worktable 1 and mainly supports the first-direction motion unit, the second-direction motion unit, and the lens assembly 52 thereon, while also guiding the movement of the lens assembly 52 along the first direction. The third-direction motion unit typically includes a linear motor, a hydraulic drive device, or a pneumatic drive device, and is mainly used to drive the carrier 7 to slide along the third direction on the worktable 1, thereby expanding the visual inspection range of the lens assembly 52 mounted on the carrier 7, and thus improving the flexibility and inspection efficiency of the alignment accuracy detection device. The worktable 1 is provided with a first guide rail 11 extending along the third direction, which supports the carrier 7 and guides and limits the movement of the carrier 7 along the third direction. The column 44 is slidably mounted on the first guide rail 11. While supporting the crossbar 43, the column 44 can also slide along the first guide rail 11 under the drive of the fifth drive member 17, thereby transmitting the motion in the third direction to the crossbar 43 and ensuring that the lens assembly 52 on the crossbar 43 can move accurately in the third direction. The third-direction motion unit includes the fifth drive member 17, which is typically a linear motor or other drive device, used to provide power for the movement of the column 44 along the first guide rail 11, ensuring that the column 44 can move smoothly and accurately along the first guide rail 11.

[0087] In one embodiment of the present invention, the alignment accuracy detection device further includes a sixth driving member 18, which can drive the column 44 to move along a first direction; the two sixth driving members 18 are respectively disposed on both sides of the column 44 along a third direction, and the two sixth driving members 18 differentially drive the column 44 to drive the bearing member 7 to move along the RZ axis direction.

[0088] In the above technical solution, the sixth driving component 18 typically includes a motor, a hydraulic drive device, or a pneumatic drive device, used to provide power for the movement of the column 44 along the first direction. Two sixth driving components 18 are respectively disposed on both sides of the column 44 along the third direction. The two sixth driving components 18 drive the column 44 to move in opposite directions, or drive the column 44 at different speeds in the same direction, forming a differential engagement. This causes the bearing component 7 to rotate along the Z-axis, finely adjusting the movement direction of the column 44 to ensure that the movement direction of the column 44 remains horizontal with the first guide rail 11, avoiding the problem of decreased movement and positioning accuracy of the column 44 and its lens assembly due to tilting.

[0089] In one embodiment of the present invention, a connector 8 is provided at the bottom of the column 44. The connector 8 covers the first guide rail 11. The connector 8 includes a third plate 81 located above the first guide rail 11 and a third side plate 82 and a fourth side plate 83 located on both sides of the first guide rail 11. Along the first direction, the side of the third side plate 82 facing the first guide rail 11 is the third inner side, and a fifth air float 821 is provided on the third inner side. The side of the fourth side plate 83 facing the first guide rail 11 is the fourth inner side, and a sixth air float 831 is provided on the fourth inner side. The fifth air float 821 and the sixth air float 831 can clamp the first guide rail 11 from both sides.

[0090] In the above technical solution, the adapter 8 provides an installation base for the fifth air-float 821 and the sixth air-float 831, connecting them to the column 44. This ensures that the column 44 is firmly fixed to the first guide rail 11 under the clamping action of the fifth air-float 821 and the sixth air-float 831. The fifth air-float 821 can press against the first guide rail 11 between the first guide rail 11 and the third inner side, and the sixth air-float 831 can press against the first guide rail 11 between the first guide rail 11 and the fourth inner side. Through the pressing cooperation of the fifth air-float 821 and the sixth air-float 831, the column 44 can be clamped and fixed to the first guide rail 11 after the carrier 7 moves to the target position. This ensures that the lens assembly 52 is not affected by the vibration or slippage of the carrier 7 when adjusting its position in the first and third directions, or when performing alignment accuracy testing, thereby improving the accuracy of the lens assembly 52's position adjustment and visual inspection.

[0091] In one embodiment of the present invention, the alignment detection device further includes a driving component that is drivenly connected to the fifth air float 821 and the sixth air float 831. The driving component typically includes components such as a hydraulic cylinder, a pneumatic cylinder, or an electric push rod, used to drive the fifth air float 821 and the sixth air float 831 to perform telescopic movements, thereby causing the fifth air float 821 and the sixth air float 831 to press against the first guide rail 11. Through the cooperation of the fifth air float 821 and the sixth air float 831, the first guide rail 11 can be pressed against from both sides, thereby achieving relative fixation between the adapter 8 and the first guide rail 11, ensuring that the adapter 8 is completely fixed on the first guide rail 11 and is not affected by any minor vibrations, thereby minimizing the jitter generated by the column 44 and the lens assembly 52 on it, and ensuring the accuracy of wafer alignment detection.

[0092] In one embodiment of the present invention, the fifth air float 821 and the sixth air float 831 are provided with air holes on their surfaces. When the adapter 8 is in an active state, air can be injected into the fifth air float 821 and the sixth air float 831 through an air source device such as a cylinder. The gas is blown out through the air holes on the surface of the air float, thereby forming an active air gap by relatively suspending the adapter 8 and the first guide rail 11. This ensures that the adapter 8 moves along the first guide rail 11 without rigid contact and friction with the first guide rail 11, reducing friction. At the same time, it avoids the movement of the adapter 8 along the first guide rail 11 being affected by the processing error and surface quality of the first guide rail 11, which would cause movement errors in the adapter 8 and the lens assembly 52 connected to it.

[0093] In one embodiment of the present invention, the sixth driving member 18 includes a second stator 181 and a second mover 182. The second stator 181 is disposed on the column 44, and the second mover 182 is disposed on the adapter 8. The second stator 181 and the second mover 182 are slidably engaged to drive the column 44 to move along a first direction.

[0094] In the above technical solution, the sixth driving component 18 is usually a linear motor or a servo motor, specifically including a second stator 181 and a second mover 182. The second stator 181 is fixedly connected to the column 44, and the second mover 182 is fixedly connected to the adapter 8. The second stator 181 interacts with the second mover 182 by generating a magnetic field, thereby driving the column 44 and other components it carries to move relative to the adapter 8 in the first direction.

[0095] In one embodiment of the present invention, the workbench 1 is further provided with a second guide rail 12 extending in a third direction, and a balance block 9 is installed on the second guide rail 12. The balance block 9 can slide along the second guide rail 12. The fifth driving member 17 includes a third stator 171 and a third mover 172. The third stator 171 is disposed on the column 44, and the third mover 172 is disposed on the balance block 9. The third stator 171 and the third mover 172 slide in cooperation to drive the column 44 and the balance block 9 to slide relative to each other in a third direction.

[0096] In the above technical solution, the second guide rail 12 is used to support the balance block 9 and can guide and limit the sliding of the balance block 9 along a third direction. According to the principle of conservation of momentum, when the column 44 moves along a third direction, if no mass generates a movement opposite to the column 44, it will cause an impact on the overall device, thereby seriously affecting the movement of other components and the detection accuracy. Therefore, the balance block 9 is set up so that when the column 44 moves, the balance block 9 can move in the opposite direction, thereby balancing the momentum generated by the movement of the column 44, significantly reducing the impact of the movement of the column 44 on other components, and thus improving the positioning accuracy of the lens assembly and the accuracy of alignment detection.

[0097] The fifth driving component 17 is typically a linear motor, specifically including a third stator 171 and a third mover 172. The third stator 171 is mounted on the column 44, and the third mover 172 is mounted on the balance block 9. The third stator 171 generates a magnetic field that interacts with the second mover 182, driving the balance block 9 to move in the third direction in the opposite direction to the movement of the column 44, with the same stroke and acceleration, thereby balancing the momentum generated by the movement of the column 44.

[0098] In one embodiment of the present invention, the third-direction motion part further includes a seventh driving member 19, which includes a fourth stator 191 and a fourth mover 192. The fourth stator 191 is disposed on the worktable 1, and the fourth mover 192 is disposed on the balance block 9. The fourth stator 191 and the fourth mover 192 are slidably engaged to drive the balance block 9 to slide along the third direction.

[0099] In the above technical solution, the seventh driving component 19 typically employs a linear motor, specifically including a fourth stator 191 and a fourth mover 192. The fourth stator 191 is mounted on the worktable 1, and the fourth mover 192 is mounted on the balance block 9. The fourth stator 191 generates a magnetic field and interacts with the fourth mover 192, driving the balance block 9 to move along a third direction. Due to the presence of external forces such as friction, when the balance block 9 moves in the third direction opposite to the direction of movement of the column 44, it cannot achieve the same stroke and acceleration change as the column 44, resulting in a balance error. Consequently, the balance block 9 cannot completely balance the momentum generated by the movement of the column 44. Therefore, the seventh driving component 19 is provided to compensate for the balance error, ensuring that the balance block 9 can generate a movement in the third direction opposite to the direction of movement of the column 44 with the same stroke and acceleration, further improving the accuracy and reliability of the balance block 9 in balancing the momentum generated by the movement of the column 44.

[0100] In one embodiment of the present invention, a first grating ruler 151 is provided on the workbench 1, which can monitor the displacement of the balance block 9 relative to the workbench 1 along the Y-axis direction; a second grating ruler 152 is provided on the balance block 9, which can monitor the displacement of the column 44 relative to the balance block 9 along the Y-axis direction; and a third grating ruler 153 is provided on the column 44, which can monitor the displacement of the workbench 1 relative to the column 44 along the Y-axis direction.

[0101] In the above technical solution, the first grating ruler 151 is set to acquire the displacement data of the balance block relative to the worktable 1 along the Y-axis direction, the second grating ruler 152 is set to acquire the displacement data of the column 44 relative to the balance block 9 along the Y-axis direction, and the third grating ruler 153 is set to acquire the displacement data of the worktable 1 relative to the column 44 along the Y-axis direction. With the joint cooperation of the first grating ruler 151, the second grating ruler 152, and the third grating ruler 153, while the fifth driving component 17 drives the column 44 and the balance block 9 to move accurately, it can provide a data basis for the seventh driving component 19 to drive the balance block 9 to move and make up for the balance error, so as to ensure that the balance block 9 can generate a movement in the third direction that is opposite to the movement direction of the column 44 and whose stroke and acceleration are completely corresponding.

[0102] In one embodiment of the present invention, the first direction motion component includes a linear motor 16, which includes a first mover 162 and a first stator 161. The first stator 161 is disposed within the crossbar 43 and extends along a first direction, and the first mover 162 is disposed on a first plate 581 or a second plate 583, with the first mover 162 and the first stator 161 in sliding engagement.

[0103] In the above technical solution, the linear motor is an electromagnetic device that directly generates linear thrust. It can directly drive the moving block 58 to move linearly along the crossbar 43. By using a linear motor, the mechanical conversion links such as reducers and gears required in traditional rotary motors are eliminated, resulting in a smaller drive structure and reduced space occupation. The first stator 161 is disposed inside the crossbar 43 and extends along the first direction, guiding the movement direction of the first mover 162. The length of the first stator 161 limits the maximum stroke of the linear motor, thereby limiting the movement range of the moving block 58. The first mover 162 is disposed on the first plate 581 or the second plate 583. As the movable part of the linear motor, the first mover 162 interacts directly with the first stator 161 on the crossbar 43, generating thrust through electromagnetic principles to push the moving block 58 to move along the first direction.

[0104] See also Figures 1 to 20 As shown, the present invention also provides a wafer inspection system, including: a worktable 1, an upper wafer motion system 2, and a lower wafer motion system 3. The upper wafer motion system 2 includes an upper wafer carrier 21 for carrying the upper wafer; the lower wafer motion system 3 includes a lower wafer carrier 31 for carrying the lower wafer. Furthermore, the wafer inspection system also includes the alignment accuracy detection device and the wafer alignment detection device described in the above embodiments. The alignment accuracy detection device is used for wafer verification and inspection after bonding, and the wafer alignment detection device is used for wafer alignment and inspection before bonding.

[0105] In the above technical solution, the workbench 1 serves as the basic structure supporting the overall device, providing a stable mounting platform for each motion system and detection system, ensuring that each component maintains a precise relative position during the bonding process. The wafer motion system consists of an upper wafer motion system 2 and a lower wafer motion system 3, which are used to control the movement of the upper and lower wafers, respectively. The upper wafer carrier 21 carries the upper wafer. By precisely controlling the movement of the upper wafer carrier 21 through the upper wafer motion system 2, the upper wafer can be accurately positioned at the bonding position. The lower wafer carrier 31 carries the lower wafer. By precisely controlling the movement of the lower wafer carrier 31 through the lower wafer motion system 3, the lower wafer can be accurately transported from the upper wafer position to the alignment and bonding positions. Through the cooperation of the upper wafer motion system 2 and the lower wafer motion system 3, the upper and lower wafers are successfully aligned and bonded. The alignment accuracy detection device described in the above embodiment can verify and detect the alignment accuracy of the bonded wafers, promptly identify defective products, and adjust the bonding device in a timely manner based on the bonding accuracy, thereby improving the yield and reducing losses caused by defective products. The wafer alignment detection device is used to perform wafer alignment detection before bonding. It aligns the upper and lower wafers before bonding to ensure high bonding accuracy of the bonded wafers, thereby improving product quality.

[0106] Existing alignment accuracy inspection devices typically only include a pre-bonding wafer inspection system. When verifying post-bonding wafers, they need to be transferred to a separate inspection device for alignment accuracy verification. This transfer of post-bonding wafers consumes additional time, increasing the bonding inspection process time and reducing production efficiency. The alignment accuracy inspection device and wafer inspection system proposed in this invention integrate the pre-bonding and post-bonding inspection systems into a single device. The pre-bonding inspection system first checks the alignment marks on the upper and lower wafers before bonding, then performs the alignment and bonding action. After bonding, the post-bonding inspection system directly verifies the alignment of the post-bonding wafers. This eliminates the intermediate transfer link from the bonding station to the alignment accuracy verification station in traditional systems, significantly shortening the transfer chain, thereby reducing the bonding inspection process time and improving overall yield.

[0107] In one embodiment of the present invention, in the wafer inspection system, the lower wafer motion system can drive the wafer to move along the Y-axis on the worktable 1, thereby transporting the wafer from the bonding position to the post-bonding inspection system, and performing alignment accuracy verification and inspection on the wafer after bonding.

[0108] In the above technical solution, the lower wafer motion system is used to carry the lower wafer before bonding and to carry the bonded wafer after bonding and drive the bonded wafer to move along the Y-axis, thereby realizing the transfer of the bonded wafer. By setting the pre-bonding inspection system and the post-bonding alignment verification inspection system on the same equipment, the distance required for transporting the bonded wafer is greatly shortened. The lower wafer motion system can realize the rapid transfer of the wafer between the bonding position and the post-bonding alignment accuracy inspection position, significantly shortening the time required for bonding and inspection processes and improving the overall yield.

[0109] In one embodiment of the present invention, the pre-bonding wafer inspection system is disposed above the upper wafer motion system, specifically including: a Y-axis motion component, a Z-axis motion component, and a vision device. The Y-axis motion component can drive the vision device to move along the Y-axis direction, and the Z-axis motion component can drive the vision device to move along the Z-axis direction. A mounting frame 4 is disposed on the worktable, and the mounting frame includes a crossbeam extending along the X-axis direction. The Y-axis motion component includes: a movable component, which is sleeved on the crossbeam and can move along the crossbeam; and an air-support component, which allows the movable component to be air-floated with the crossbeam.

[0110] In the above technical solution, the Y-axis motion component provides the vision device with a degree of freedom along the Y-axis, enabling it to move and adjust its position. The Z-axis motion component provides the vision device with a vertical degree of freedom, allowing it to move and adjust its position along the Z-axis. The crossbeam supports the movable component and guides its movement along the Y-axis. The air-supported component utilizes the principle of air levitation to suspend the movable component relative to the crossbeam, reducing direct contact between the movable component and the crossbeam. By incorporating the air-supported component, friction between the movable component and the crossbeam during movement is avoided, preventing vibration and displacement caused by the crossbeam's machining accuracy and surface quality. This significantly improves the stability of the vision device's movement, ensuring precise positioning during wafer inspection and enhancing inspection accuracy. Furthermore, it avoids wear problems caused by direct contact between the movable component and the crossbeam.

[0111] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects: the first direction motion part can provide the lens assembly 52 with a degree of freedom along the first direction, and the second direction motion part 59 can provide the lens assembly 52 with a degree of freedom along the second direction. The first direction and the second direction are perpendicular to each other, so that the first direction motion part and the second direction motion part 59 cooperate with each other to drive the lens assembly 52 to move precisely in two directions in the X, Y, and Z three-dimensional coordinate system to locate different detection positions. The lens assembly 52 is responsible for capturing images of the wafer for alignment accuracy analysis and detection. The support member 7 provides a stable foundation, while the crossbar 43 serves as a guide structure for the first direction motion part, ensuring smooth and linear movement of the lens assembly 52 along the first direction, reducing wobbling and deviation during the movement of the lens assembly 52, and improving the stability and positioning accuracy of the lens assembly 52. ​​The moving block 58 is used to support the lens assembly 52 and drive the lens assembly 52 to move along the crossbar 43. The air-supported component can form an air-float gap between the moving block 58 and the crossbar 43, thereby suspending the moving block 58 relative to the crossbar 43.

[0112] The alignment accuracy detection device provided by the present invention enables the moving block 58 to suspend relative to the crossbar 43 through the cooperation of the air foot component and the moving block 58. This avoids the moving block 58 from contacting and rubbing against the crossbar 43 during movement and from vibrating and shifting due to the influence of the crossbar 43's processing accuracy and surface quality. As a result, it significantly improves the stability of the lens assembly 52's movement, ensures the precise positioning of the lens assembly during wafer inspection, and improves the detection accuracy.

[0113] Obviously, the embodiments described above are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort should fall within the scope of protection of the present invention.

[0114] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0115] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An alignment accuracy detection device, characterized in that, include: The system comprises a first direction motion unit, a second direction motion unit (59), and a lens assembly (52). The first direction motion unit is capable of driving the lens assembly (52) to move along a first direction, and the second direction motion unit (59) is capable of driving the lens assembly (52) to move along a second direction. The first direction and the second direction are perpendicular to each other. The support member (7) includes a crossbar (43) extending along the first direction; The first directional movement part includes: a moving block (58), which is sleeved on the crossbar (43) and can move along the crossbar (43); The air-supported component allows the moving block (58) to be air-floated with the crossbar (43).

2. The alignment accuracy detection device according to claim 1, characterized in that, The movable block (58) includes a first plate (581) located below the crossbar (43) and a second plate (583) located above the crossbar (43); The air-supported component includes a first positive pressure part and a second positive pressure part. The first positive pressure part is disposed on the first plate (581) or the crossbar (43); the second positive pressure part is disposed on the second plate (583) or the crossbar (43).

3. The alignment accuracy detection device according to claim 2, characterized in that, The air-supported component further includes: a first negative pressure part, which is disposed on the first plate (581) or the crossbar (43); the first negative pressure part can generate negative pressure to adsorb and fix the crossbar (43) and the first plate (581) together; The air foot component also includes a first air cushion (5871) and a first driving member connected by a drive. The first air cushion (5871) is disposed on one of the second plate (583) and the crossbar (43). The first driving member can drive the first air cushion (5871) to move, so as to provide the first air cushion (5871) with a force that can press against the other of the second plate (583) and the crossbar (43).

4. The alignment accuracy detection device according to claim 2, characterized in that, The air-supported component further includes a second negative pressure part, which is disposed on the second plate (583) or the crossbar (43); the second negative pressure part can generate negative pressure to attract and fix the crossbar (43) and the second plate (583) together; The air foot component also includes a second air cushion and a second driving member connected by a drive. The second air cushion is disposed on one of the first plate (581) and the crossbar (43). The second driving member can drive the second air cushion to move, so as to provide the second air cushion with a force that can press against the other of the first plate (581) and the crossbar (43).

5. The alignment accuracy detection device according to claim 2, characterized in that, The air foot component further includes: a third air cushion and a third driving member connected by a drive. The third air cushion is disposed on one of the second plate (583) and the crossbar (43). The third driving member can drive the third air cushion to move, so as to provide the third air cushion with a force that can press against the other of the second plate (583) and the crossbar (43). The air foot component also includes a fourth air float and a fourth driving member connected by a drive. The fourth air float is disposed on one of the first plate (581) and the crossbar (43). The fourth driving member can drive the fourth air float to move, so as to provide the fourth air float with a force that can press against the other of the first plate (581) and the crossbar (43).

6. The alignment accuracy detection device according to claim 2, characterized in that, The movable block (58) includes a first side plate (5821) and a second side plate (5822) located on both sides of the crossbar (43). The second direction movement part (59) is provided on the outer side of the first side plate (5821), and a counterweight block (588) is provided on the outer side of the second side plate (5822).

7. The alignment accuracy detection device according to claim 6, characterized in that, At least one of the first side plate (5821) and the second side plate (5822) includes an inner side plate (584) and an outer side plate (585), which are connected by a flexible hinge (586).

8. The alignment accuracy detection device according to claim 6, characterized in that, Along the third direction, the side of the first side plate (5821) facing the crossbar (43) is the first inner side, and the side of the second side plate (5822) facing the crossbar (43) is the second inner side. The first direction, the second direction, and the third direction are all perpendicular to each other. The air supply component further includes a first air flotation block (5872) and a second air flotation block (5873), wherein the first air flotation block (5872) is disposed on the first inner side surface; and the second air flotation block (5873) is disposed on the second inner side surface.

9. The alignment accuracy detection device according to claim 8, characterized in that, The air foot component also includes: A first adjusting member and a second adjusting member, wherein the first adjusting member is driven to connect the first air flotation block and the second adjusting member is driven to connect the second air flotation block; the first adjusting member is used to adjust the gap between the first air flotation block and the crossbar (43) and the second adjusting member is used to adjust the gap between the second air flotation block and the crossbar (43).

10. The alignment accuracy detection device according to claim 1, characterized in that, The alignment accuracy detection device also includes a worktable (1) and a third-direction motion unit. The carrier (7) is disposed on the worktable (1), and the third-direction motion unit can drive the carrier (7) to slide along the third direction. The workbench (1) is provided with a first guide rail (11) extending in a third direction. The support member (7) includes columns (44) disposed at both ends of the crossbar. The columns (44) are slidably mounted on the first guide rail (11). The third-direction moving part includes a fifth driving member (17). The fifth driving member (17) can drive the columns (44) to move along the first guide rail (11).

11. The alignment accuracy detection device according to claim 10, characterized in that, The accuracy detection device further includes a sixth driving member (18), which can drive the column (44) to move along a first direction; The two sixth driving members (18) are respectively disposed on both sides of the column (44) along the third direction. The two sixth driving members (18) differentially drive the column (44) to drive the bearing member (7) to move along the RZ axis.

12. The alignment accuracy detection device according to claim 11, characterized in that, The bottom of the column (44) is provided with a connector (8), which covers the first guide rail (11). The connector (8) includes a third plate (81) located above the first guide rail (11) and a third side plate (82) and a fourth side plate (83) located on both sides of the first guide rail (11). Along the first direction, the side of the third side plate (82) facing the first guide rail (11) is the third inner side, and a fifth air float (821) is provided on the third inner side. The side of the fourth side plate (83) facing the first guide rail is the fourth inner side, and a sixth air float (831) is provided on the fourth inner side. The fifth air float (821) and the sixth air float (831) can clamp the first guide rail (11) from both sides. The sixth driving member (18) includes a second stator (181) and a second mover (182). The second stator (181) is disposed on the column (44), and the second mover (182) is disposed on the adapter (8). The second stator (181) and the second mover (182) are slidably engaged to drive the column (44) to move along the first direction.

13. The alignment accuracy detection device according to claim 11, characterized in that, The workbench (1) is also provided with a second guide rail (12) extending in a third direction, and a balance block (9) is installed on the second guide rail (12). The balance block (9) can slide along the second guide rail (12). The fifth driving component (17) includes a third stator (171) and a third mover (172). The third stator (171) is disposed on the column (44), and the third mover (172) is disposed on the balance block (9). The third stator (171) and the third mover (172) are slidably engaged to drive the column (44) and the balance block (9) to slide relative to each other along the third direction.

14. The alignment accuracy detection device according to claim 13, characterized in that, The third-direction motion unit also includes a seventh drive member (19), which includes a fourth stator (191) and a fourth mover (192). The fourth stator (191) is disposed on the worktable (1), and the fourth mover (192) is disposed on the balance block (9). The fourth stator (191) and the fourth mover (192) are slidably engaged to drive the balance block (9) to slide along the third direction.

15. A wafer inspection system, comprising: Workbench (1); The upper wafer motion system (2) includes an upper wafer carrier (21) for carrying the upper wafer; The lower wafer motion system (3) includes a lower wafer carrier (31) for carrying the lower wafer; Its characteristic is that it further includes: The alignment accuracy detection device according to any one of claims 1 to 14 is used for wafer verification and detection after bonding. as well as: A wafer alignment and inspection device is used to perform wafer alignment and inspection before bonding.

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