Wafer illumination beam stabilizing system and method

Abstract

The application provides a wafer illumination beam stabilizing system and method, belonging to the technical field of wafer defect detection, which comprises the following steps: a light source beam is refracted and reflected by an illumination assembly to form two light beams; a second light beam is shot to a workpiece on a workpiece moving assembly; the second light beam forms a second light spot on the workpiece and reflects a third light beam; the third light beam is shot to a reflection monitoring assembly to form a third light spot; the reflection monitoring assembly monitors the position of the second light spot by monitoring the position of the third light spot formed by the third light beam; a signal control assembly obtains the position information of the second light spot according to the position information of the third light spot sent by the reflection monitoring assembly, and transmits a control signal to the workpiece moving assembly to control the workpiece moving assembly to move, so that the second light spot can illuminate a specified position of the workpiece each time the workpiece is detected for defects, which is favorable for improving the accuracy of defect detection and can adapt to different defect detection modes, and has a wide range of applications.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of wafer defect detection, and particularly relates to a wafer illumination light beam stabilizing system and method. BACKGROUND

[0002] In semiconductor detection, a wafer is irradiated by active laser, a laser spot is focused on a position on the wafer, the wafer surface defects are irradiated, and scattered light or illumination areas are collected and processed to correspond to the wafer defect position, so as to detect the wafer defects. However, in the actual detection process, the changes of the wafer angle and height will affect the position of the laser spot focused on the wafer, causing the spot to deviate from the specified position of the objective field of view, even beyond the objective field of view, affecting the defect feedback signal, causing the defect position and type to be different or even wrong, and affecting the accuracy of the detection result. SUMMARY

[0003] The present application aims to at least solve one of the problems in the prior art or related art.

[0004] To this end, the first aspect of the present application provides a wafer illumination light beam stabilizing system.

[0005] The second aspect of the present application provides a wafer illumination light beam stabilizing method.

[0006] Therefore, according to the first aspect of the embodiments of the present application, a wafer illumination light beam stabilizing system is provided, which is arranged on a platform, and comprises:

[0007] An illumination assembly, which refracts a light source beam to form at least a first light beam and a second light beam, is adjustably arranged on the platform to adjust the light splitting angle of the light source beam;

[0008] A workpiece moving assembly, which is used to move a workpiece to be tested, receives the second light beam and can reflect a third light beam;

[0009] A reflection monitoring assembly, which is used to monitor the spot formed by the third light beam;

[0010] A signal control assembly, which is used to control the movement of the workpiece moving assembly, receives the detection signal of the reflection monitoring assembly, and transmits a control signal to the workpiece moving assembly according to at least the detection signal of the reflection monitoring assembly.

[0011] In a feasible implementation, the illumination assembly comprises a light beam adjusting assembly, a prism assembly and a light beam focusing assembly, the light beam adjusting assembly reflects the light source beam onto the prism assembly, the prism assembly splits the light to form the first light beam and the second light beam, and the second light beam enters the light beam focusing assembly;

[0012] The light beam adjusting assembly is adjustably arranged on the platform to adjust the angle of the first light beam and the second light beam.

[0013] In an embodiment, the light beam adjusting assembly comprises:

[0014] The fast mirror seat;

[0015] The adjusting system is electrically connected with the signal control assembly, and comprises a first adjusting mechanism, which is arranged on the fast mirror seat.

[0016] The fast mirror lens is arranged on the first adjusting mechanism.

[0017] In an embodiment, the optical system of the light beam focusing assembly is a reverse telephoto system, and the light beam focusing assembly comprises:

[0018] The focusing lens barrel support;

[0019] The focusing lens barrel is arranged on the focusing lens barrel support.

[0020] The focusing lens barrel is arranged on the focusing lens barrel support.

[0021] In an embodiment, the workpiece moving assembly is arranged with a workpiece to be measured, and is used for moving the workpiece to be measured.

[0022] The workpiece moving assembly comprises:

[0023] The base;

[0024] The second adjusting mechanism is electrically connected with the signal control assembly, and is arranged on the base.

[0025] The rotating mechanism is electrically connected with the signal control assembly, and is arranged on the moving table of the second adjusting mechanism, and comprises a rotating table, on which the workpiece to be measured is arranged.

[0026] In an embodiment, the reflection monitoring assembly comprises a reflection monitoring mirror group assembly, a reflection monitoring turning mirror assembly and a reflection monitoring detector assembly, the reflection monitoring turning mirror assembly is arranged on the light exit side of the reflection monitoring mirror group assembly, and the reflection monitoring detector assembly is arranged on the light exit side of the reflection monitoring turning mirror assembly.

[0027] In an embodiment, the optical system of the reflection monitoring mirror group assembly is a long-focus focusing system, and the reflection monitoring mirror group assembly comprises:

[0028] The reflection monitoring lens barrel support;

[0029] The reflection monitoring lens barrel is arranged on the reflection monitoring lens barrel support.

[0030] The reflection monitoring lens barrel is arranged on the reflection monitoring lens barrel support.

[0031] In an embodiment, the wafer illumination light beam stabilizing system further comprises:

[0032] The light source monitoring assembly receives the first light beam, and monitors a light spot formed by the first light beam.

[0033] In an embodiment, the signal control assembly receives the detection signal of the light source monitoring assembly, and transmits a control signal to the illumination assembly according to the detection signal of the light source monitoring assembly.

[0034] In an embodiment, the light source monitoring assembly comprises a light source monitoring lens group assembly and a light source monitoring detector assembly, and the light source monitoring detector assembly is arranged on the light exit side of the light source monitoring lens group assembly.

[0035] In an embodiment, the optical system of the light source monitoring lens group assembly is a long-focus focusing system, and the light source monitoring lens group assembly comprises:

[0036] The monitoring lens barrel support;

[0037] The monitoring lens barrel is arranged on the monitoring lens barrel support;

[0038] The monitoring lens barrel is arranged on the monitoring lens barrel support.

[0039] According to the second aspect of the embodiment of the present application, a wafer illumination light beam stabilizing method is provided, which uses the wafer illumination light beam stabilizing system according to any of the above technical solutions to detect a wafer, comprising:

[0040] The illumination assembly divides the light source light beam into a first light beam and a second light beam, focuses the second light beam onto the to-be-detected workpiece installed on the workpiece moving assembly to form a third light beam, and reflects the third light beam into the reflection monitoring assembly to form a light spot;

[0041] Obtain the first initial position of the light spot monitored by the reflection monitoring assembly;

[0042] Collect the first adjusted position of the light spot monitored by the reflection monitoring assembly;

[0043] According to the first adjusted position and the first initial position recorded by the reflection monitoring assembly, obtain the first offset of the light spot monitored by the reflection monitoring assembly;

[0044] According to the first offset of the light spot monitored by the reflection monitoring assembly, adjust the workpiece moving assembly.

[0045] In one possible implementation, the first offset of the light spot monitored by the reflection monitoring assembly is obtained according to the first adjusted position recorded by the reflection monitoring assembly and the first initial position, and the step comprises:

[0046] an angle offset of the light source beam in the X direction Δθ x an angle offset of the light source beam in the Y direction Δθ Y a surface angle of the workpiece in the X direction a surface angle of the workpiece in the Y direction

[0047] the first offset of the light spot monitored by the reflection monitoring assembly in the X direction ΔT x the first offset of the light spot monitored by the reflection monitoring assembly in the Y direction ΔT Y is calculated according to the following formula relationship:

[0048]

[0049] wherein Δθ x is the angle offset of the light source beam in the X direction, Δθ Y is the angle offset of the light source beam in the Y direction, is the surface angle of the workpiece in the X direction, is the surface angle of the workpiece in the Y direction, ΔZ is the adjustment amount of the light spot of the second light beam on the workpiece in the Z direction, F x , F Y , G, H x , H Y are known corresponding system parameter coefficients.

[0050] In one possible implementation, the third light beam is reflected into the reflection monitoring assembly to form a light spot, and then the method further comprises:

[0051] When detecting for the first time, after the workpiece is installed, the position of the light spot monitored by the reflection monitoring assembly is adjusted by adjusting the illumination assembly;

[0052] When continuously detecting, after the workpiece is replaced, the position of the light spot monitored by the reflection monitoring assembly is adjusted by adjusting the illumination assembly and / or the workpiece moving assembly.

[0053] In one possible implementation, the workpiece moving assembly is adjusted, and the method further comprises:

[0054] When the first offset is greater than a preset value, the signal control assembly at least controls the workpiece moving assembly to move;

[0055] When the first offset is not greater than the preset value, the illumination assembly and the workpiece moving assembly stop moving.

[0056] In one possible implementation, in the case that the wafer illumination beam stabilizing system comprises a light source monitoring assembly, the step of adjusting the workpiece moving assembly according to the first displacement of the light spot monitored by the reflection monitoring assembly comprises:

[0057] recording a second initial position of the light spot monitored by the light source monitoring assembly, collecting a second pre-adjustment position of the light spot monitored by the light source monitoring assembly;

[0058] obtaining a second displacement of the light spot monitored by the light source monitoring assembly according to the second pre-adjustment position and the second initial position recorded by the light source monitoring assembly;

[0059] adjusting the workpiece moving assembly and / or the illumination assembly according to the first displacement and the second displacement.

[0060] In one possible implementation, obtaining a second displacement of the light spot monitored by the light source monitoring assembly according to the second pre-adjustment position and the second initial position recorded by the light source monitoring assembly comprises:

[0061] obtaining an angular displacement of the light source beam in the X direction Δθ x , an angular displacement of the light source beam in the Y direction Δθ Y , a positional displacement of the light source beam in the X direction Δω x , and a positional displacement of the light source beam in the Y direction Δω Y ;

[0062] calculating the second displacement of the light spot monitored by the light source monitoring assembly in the X direction ΔU x and the second displacement in the Y direction ΔU Y according to the following formula relationship:

[0063] ΔU x = A x Δθ x + B x Δω x ;

[0064] ΔU Y = A Y Δθ Y + B Y Δω Y ;

[0065] wherein Δθ x is the angular displacement of the light source beam in the X direction, Δθ Y is the angular displacement of the light source beam in the Y direction, Δω x is the positional displacement of the light source beam in the X direction, and Δω YA is a position offset of the light source light beam in the Y direction x A Y B x B Y are known corresponding system parameter coefficients.

[0066] In one possible implementation, adjusting the workpiece moving assembly and / or the lighting assembly according to the first offset and the second offset includes:

[0067] The adjustment amount ΔX of the light spot on the surface of the workpiece in the X direction, the adjustment amount ΔY in the Y direction, and the adjustment amount ΔZ in the Z direction are calculated according to the following formula relationship:

[0068]

[0069] wherein ΔX is the adjustment amount of the light spot on the surface of the workpiece in the X direction, ΔY is the adjustment amount in the Y direction, and ΔZ is the adjustment amount of the light spot of the second light beam on the workpiece in the Z direction, ΔT x is the first offset of the light spot in the X direction monitored by the reflection monitoring assembly, ΔT Y is the first offset of the light spot in the Y direction monitored by the reflection monitoring assembly, ΔU x is the second offset of the light spot in the X direction monitored by the light source monitoring assembly, ΔU Y is the second offset of the light spot in the X direction monitored by the light source monitoring assembly; and Δθ x is an angle offset of the light source light beam in the X direction, C x C Y D, F x G are known corresponding system parameter coefficients.

[0070] In one possible implementation, before adjusting the workpiece moving assembly and / or the lighting assembly, the following steps are included:

[0071] an allowable variation I x of the light spot on the workpiece in the Y direction, I Y of the light spot on the workpiece in the X direction, I x is adjusted when the following formula relationship is satisfied:

[0072]

[0073] wherein I x is the allowable variation of the light spot on the workpiece in the X direction, I Y is the allowable variation of the light spot on the workpiece in the Y direction, and Δθ x is an angle offset of the light source light beam in the X direction, and Δθ Yan angle offset of the light beam of the light source in the Y direction, a surface angle of the workpiece in the X direction, a surface angle of the workpiece in the Y direction, ΔZ is an adjustment amount of the spot of the second light beam on the workpiece in the Z direction, C x , C Y , D, E x , E Y are known corresponding system parameter coefficients.

[0074] In an implementable embodiment, the workpiece moving assembly and / or the lighting assembly are adjusted, and then the following steps are included:

[0075] the adjusted position of the spot monitored by the reflection monitoring assembly is collected, and a third offset amount of the spot monitored by the reflection monitoring assembly after adjustment is obtained according to the adjusted position recorded by the reflection monitoring assembly and the first initial position;

[0076] whether the lighting assembly and / or the workpiece moving assembly need to be continuously adjusted is determined according to the third offset amount.

[0077] In an implementable embodiment, the workpiece moving assembly is adjusted, and before that the following steps are included:

[0078] when the third offset amount is greater than a preset value, the signal control assembly at least controls the workpiece moving assembly to move;

[0079] when the third offset amount is not greater than the preset value, the lighting assembly and the workpiece moving assembly stop moving.

[0080] Compared with the prior art, the wafer illumination light beam stabilizing system and method provided in the application has the following beneficial effects:

[0081] The wafer illumination light beam stabilizing system provided in the embodiment of the application includes a lighting assembly, a workpiece moving assembly, a reflection monitoring assembly, and a signal control assembly. The light beam emitted by a light source is refracted and reflected by the lighting assembly itself to form two light beams. The second light beam is directed to a workpiece on the workpiece moving assembly, forms a second spot on the workpiece, and reflects a third light beam. The third light beam is directed to the reflection monitoring assembly to form a third spot. The reflection monitoring assembly monitors the position of the second spot formed by the second light beam by monitoring the position of the third spot formed by the third light beam. The signal control assembly obtains the position information of the second spot according to the position information of the third spot received from the reflection monitoring assembly, transmits a control signal to the workpiece moving assembly, and controls the workpiece moving assembly to move. In this way, the specified position of the workpiece can be illuminated by the second spot every time the workpiece is detected for defects, which is conducive to improving the accuracy of defect detection and can adapt to different defect detection modes, and thus the application range is wide. BRIEF DESCRIPTION OF DRAWINGS

[0082] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments with reference made to the accompanying drawings. The drawings are for purposes of illustration only and are not intended to be limiting in

[0083] Figure 1 A schematic structural diagram of a first angle of a wafer illumination light beam stabilizing system according to an embodiment of the present application;

[0084] Figure 2 A schematic structural diagram of a second angle of a wafer illumination light beam stabilizing system according to an embodiment of the present application;

[0085] Figure 3 A schematic working principle diagram of a wafer illumination light beam stabilizing system according to an embodiment of the present application;

[0086] Figure 4 A schematic structural diagram of an illumination assembly of a wafer illumination light beam stabilizing system according to an embodiment of the present application;

[0087] Figure 5 A schematic structural diagram of a light source monitoring assembly of a wafer illumination light beam stabilizing system according to an embodiment of the present application;

[0088] Figure 6 A schematic structural diagram of a workpiece moving assembly of a wafer illumination light beam stabilizing system according to an embodiment of the present application;

[0089] Figure 7 A schematic structural diagram of a reflection monitoring assembly of a wafer illumination light beam stabilizing system according to an embodiment of the present application;

[0090] Figure 8 A schematic control principle diagram of a wafer illumination light beam stabilizing system according to an embodiment of the present application;

[0091] Figure 9 A schematic working flow diagram of a wafer illumination light beam stabilizing method according to an embodiment of the present application;

[0092] Correspondence between reference signs in the drawings and component names is as follows: Figures 1 to 9

[0093] 1. Illumination assembly; 2. Light source monitoring assembly; 3. Workpiece moving assembly; 4. Reflection monitoring assembly; 5. Signal control assembly; 6. Workpiece to be measured;

[0094] 11. Light beam adjusting assembly; 12. Prism assembly; 13. Light beam focusing assembly;

[0095] ​111, quick mirror holder; 112, adjusting system; 113, quick mirror lens;

[0096] 21, light source monitoring mirror group assembly; 22, light source monitoring detector assembly;

[0097] 211, monitoring mirror tube support; 212, monitoring mirror tube; 213, monitoring lens;

[0098] 31, base; 32, second adjusting mechanism; 33, rotating mechanism;

[0099] 41, reflective monitoring mirror group assembly; 42, reflective monitoring turning mirror assembly; 43, reflective monitoring detector assembly;

[0100] 411, reflective monitoring mirror tube support; 412, reflective monitoring mirror tube; 413, reflective monitoring lens. DETAILED DESCRIPTION

[0101] In the description of the present application, it needs to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise" and the like indicate the orientation or positional relationship shown in the drawings, which are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0102] In addition, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more of the features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0103] In the present application, unless otherwise specifically defined and limited, the terms "mounting", "connection", "connection", "fixing" and the like should be understood broadly, for example, it can be fixed connection, or detachable connection, or integral connection; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium, or the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0104] The preferred embodiments of the present application are described below in conjunction with the accompanying drawings, it should be understood that the preferred embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0105] As shown in Figures 1 to 3 According to the first aspect of the embodiments of the present application, a wafer illumination beam stabilizing system is provided, which is arranged on a platform and comprises an illumination assembly 1, a workpiece moving assembly 3, a reflection monitoring assembly 4, and a signal control assembly 5. The illumination assembly 1 refracts a light beam of a light source to form at least a first light beam and a second light beam. The illumination assembly 1 is arranged on the platform in a manner that can be adjusted to adjust the splitting angle of the light beam of the light source. The workpiece moving assembly 3 is used to move a workpiece 6 to be measured, which receives the second light beam and can reflect a third light beam. The reflection monitoring assembly 4 is used to monitor the light spot formed by the third light beam. The signal control assembly 5 is used to control the movement of the workpiece moving assembly 3. The signal control assembly 5 receives the detection signal of the reflection monitoring assembly 4 and transmits a control signal to the workpiece moving assembly 3 according to at least the detection signal of the reflection monitoring assembly 4.

[0106] The wafer illumination beam stabilizing system provided by the embodiments of the present application comprises the illumination assembly 1, the workpiece moving assembly 3, the reflection monitoring assembly 4, and the signal control assembly 5. The light beam emitted by the light source is refracted and reflected by the illumination assembly 1 to form two light beams. The second light beam is directed to the workpiece 6 to be measured on the workpiece moving assembly 3. The second light beam forms a second light spot on the workpiece 6 to be measured and reflects a third light beam. The third light beam is directed to the reflection monitoring assembly 4 to form a third light spot. The reflection monitoring assembly 4 monitors the position of the second light spot formed by the second light beam by monitoring the position of the third light spot formed by the third light beam. The signal control assembly 5 obtains the position information of the second light spot according to the position information of the third light spot received from the reflection monitoring assembly 4, transmits a control signal to the workpiece moving assembly 3, and controls the movement of the workpiece moving assembly 3. In this way, the specified position of the workpiece 6 to be measured can be illuminated by the second light spot each time the workpiece 6 to be measured is detected for defects, which is conducive to improving the accuracy of defect detection and can adapt to different defect detection modes, thereby having a wide range of applications.

[0107] In some examples, the reflection monitoring assembly 4 can only be configured to monitor the system. The third light beam is reflected by the wafer on the workpiece moving assembly 3 and enters the reflection monitoring assembly 4. The position of the third light spot in the reflection monitoring assembly 4 is monitored by the reflection monitoring assembly 4. The position of the second light spot on the wafer is obtained by calculation through the signal control assembly 5, and then the detection system performs defect detection.

[0108] In some examples, the reflection monitoring assembly 4 can also be configured to observe the system. The position of the second light spot on the wafer is directly observed by the observation system carried by the reflection monitoring assembly 4, and the observation system carried by the reflection monitoring assembly 4 directly performs defect detection on the wafer.

[0109] As shown in Figures 1 to 3As shown in a feasible implementation, the wafer illumination beam stabilizing system further comprises a light source monitoring assembly 2; the light source monitoring assembly 2 receives the first light beam, and the light source monitoring assembly 2 monitors the light spot formed by the first light beam.

[0110] In the technical solution, the light source light beam is refracted and reflected by the illumination assembly 1 itself to form two light beams, the first light beam is received by the light source monitoring assembly 2 and a first light spot is formed on the light source monitoring assembly 2, and the light source monitoring assembly 2 monitors the position of the first light spot.

[0111] As shown in a feasible implementation, the signal control assembly 5 receives the detection signal of the light source monitoring assembly 2, and the signal control assembly 5 transmits a control signal to the illumination assembly 1 according to the detection signal of the light source monitoring assembly 2. Figures 1 to 3

[0112] In the technical solution, the signal control assembly 5 monitors whether the illumination assembly 1 and the workpiece moving assembly 3 work normally according to the position information of the first light spot received by the light source monitoring assembly 2, that is, the light source monitoring assembly 2 monitors whether the adjustment of the illumination assembly 1 and the workpiece moving assembly 3 is accurate and effective, and feeds back to the signal control assembly 5, the signal control assembly 5 calculates the adjustment amount of the workpiece moving assembly 3 and the illumination assembly 1 by calculating the comprehensive information of the light source monitoring assembly 2 and the reflection monitoring assembly 4, and transmits a corresponding control signal to control the movement of the workpiece moving assembly 3 and / or the illumination assembly 1, so that the system has a self-monitoring function, and the accuracy of the position adjustment of the second light spot is ensured.

[0113] It can be understood that the reflection monitoring assembly 4 monitors the third light spot and collects the position signal of the third light spot, the reflection monitoring assembly 4 transmits the position signal of the third light spot to the signal control assembly 5, the signal control assembly 5 calculates the position of the second light spot on the wafer according to the position signal of the third light spot, and then adjusts the workpiece moving assembly 3. The light source monitoring assembly 2 monitors the first light spot and collects the position signal of the first light spot, the light source monitoring assembly 2 transmits the position signal of the first light spot to the signal control assembly 5, and the signal control assembly 5 adjusts the illumination assembly 1 according to the position signal of the first light spot.

[0114] It can be understood that, as shown in a feasible implementation, the signal control assembly 5 is electrically connected with the illumination assembly 1, the light source monitoring assembly 2, the workpiece moving assembly 3, and the reflection monitoring assembly 4, the signal control assembly 5 receives the light spot position signals monitored by the light source monitoring assembly 2 and the reflection monitoring assembly 4, and the signal control assembly 5 transmits a control signal to the illumination assembly 1 and / or the workpiece moving assembly 3 after processing. Figure 8

[0115] ​​Further, the signal control component 5 is a hardware control system, the signal control component 5 processes signals and algorithms to obtain the adjustment amount of the lighting component 1 and the workpiece moving component 3, and transmits the signals to the actuators in the lighting component 1 and the workpiece moving component 3 to realize high-precision closed-loop control of the wafer illumination beam stabilizing system.

[0116] Further, the workpiece 6 to be measured is installed on the workpiece moving component 3, and the workpiece moving component 3 drives the workpiece 6 to be measured to move and / or adjusts the position of the lighting component 1 to adjust the position of the second light beam on the wafer, so that the light source light beam can illuminate the specified position of the wafer, including but not limited to the centroid, the centroid or other geometric center of the wafer, so that the light spot of the light source light beam converging on the workpiece 6 to be measured can be in the specified position of the field of view of the objective lens each time the workpiece 6 to be measured is replaced, improving the accuracy of the defect feedback signal, reducing the difference and error in defect position and type calibration, and thus improving the accuracy of the detection result.

[0117] In a feasible implementation, the stabilizing system can only serve as a light beam stabilizing system to adjust the illumination position of the light source light beam on the wafer, quickly and real-timely adjust the light source light beam, and realize automatic focusing of the light beam. When the stabilizing system is used as a light beam stabilizing system, the scanning camera objective lens is located above the wafer, the wafer is driven to move by the workpiece moving component 3 to cooperate with the scanning of the scanning camera on the upper surface of the wafer, so that the illumination position of the second light spot is located in the field of view of the objective lens of the scanning camera, and dark-field defect detection of the wafer is realized.

[0118] In a feasible implementation, the stabilizing system can also directly serve as a defect detection system to adjust the illumination position of the light source light beam on the wafer, quickly and real-timely adjust the light source light beam. When the stabilizing system is used as a defect detection system, the reflection monitoring component 4 can be configured with a shooting camera to make the reflection monitoring component 4 have a shooting function, adjust the movement of the lighting component 1 according to a preset scanning track, cooperate with the movement of the wafer driven by the workpiece moving component 3 to maintain the illumination of the second light spot on the specified position, and then directly observe the wafer surface area irradiated by the light source light beam by the shooting camera, identify the wafer surface defects through algorithm processing, directly observe the wafer, and realize bright-field defect detection of the wafer.

[0119] It can be understood that, according to different workpieces 6 to be measured and different scanning modes, the signal control component 5 can transmit signals to the actuators in the lighting component 1 and the workpiece moving component 3 to realize specified track scanning detection of the wafer. The scanning track of the light source light beam and the workpiece moving component 3 can realize various scanning modes such as linear scanning and spiral scanning.

[0120] As Figure 4As shown, in one feasible embodiment, the lighting assembly 1 includes a beam adjustment assembly 11, a prism assembly 12, and a beam focusing assembly 13. The beam adjustment assembly 11 reflects the light source beam onto the prism assembly 12, and the prism assembly 12 splits the light source beam to form a first beam and a second beam. The first beam enters the light source monitoring assembly 2, and the second beam enters the beam focusing assembly 13. The beam adjustment assembly 11 is adjustablely mounted on the platform to adjust the angle between the first beam and the second beam.

[0121] In this technical solution, the incident light beam is reflected by the beam adjustment component 11 onto the prism component 12. The prism component 12 splits the light beam reflected by the beam adjustment component 11 into two beams. The first beam enters the light source monitoring component 2 and forms a first light spot on the light source monitoring component 2. The second beam enters the beam focusing component 13 and is focused onto the surface of the test piece 6, forming a second light spot on the surface of the test piece 6. The position of the beam adjustment component 11 is controlled by the signal control component 5 to adjust the splitting angle between the first and second beams, thereby adjusting the position of the first light spot in the light source monitoring component 2 and the position of the second light spot on the test piece 6, so that the second light spot can illuminate a designated position of the test piece 6.

[0122] Furthermore, the prism assembly 12 includes a prism and a prism mount, with the prism fixed on the prism mount.

[0123] In some examples, the first beam is refracted by the prism assembly 12 itself and enters the light source monitoring assembly 2, while the second beam is reflected by the prism assembly 12 itself and enters the beam focusing assembly 13.

[0124] like Figure 4 As shown, in one feasible embodiment, the beam adjustment assembly 11 includes: a fast-reflecting mirror mount 111, an adjustment system 112, and a fast-reflecting mirror lens 113; the adjustment system 112 is electrically connected to the signal control assembly 5, the adjustment system 112 includes a first adjustment mechanism, and the adjustment system 112 is disposed on the fast-reflecting mirror mount 111; the fast-reflecting mirror lens 113 is disposed on the first adjustment mechanism.

[0125] In this technical solution, the fast-reflecting mirror lens 113 is mounted on the first adjustment mechanism of the adjustment system 112. The signal control component 5 transmits a control signal to the adjustment system 112, causing the first adjustment mechanism to move the fast-reflecting mirror lens 113, thereby changing the angle of the first beam and the second beam split from the light source beam. This adjusts the position of the first spot formed by the first beam in the light source monitoring component 2 and the position of the second spot formed by the second beam on the test piece 6. By adjusting the position of the fast-reflecting mirror lens 113 through the signal control component 5, it is ensured that the second spot can illuminate the designated position of the test piece 6.

[0126] Further, the adjusting system 112 can adopt a piezoelectric drive response system to quickly respond to the control signal of the signal control component 5; the first adjusting mechanism is provided with a quick mirror lens 113, and the quick mirror lens 113 moves with the first adjusting mechanism relative to the quick mirror seat 111.

[0127] In some examples, when the adjusting system 112 of the lighting assembly 1 adopts a piezoelectric drive response system with angle or position feedback, the lighting assembly 1 does not rely on the first light spot position monitored by the light source monitoring assembly 2 for adjustment, but only relies on the adjusting system 112 of the lighting assembly 1 for adjustment, which is fast in feedback and high in adjustment efficiency.

[0128] In some examples, when the adjusting system 112 of the lighting assembly 1 is electrically connected with the signal control component 5 and the first light beam irradiates on the light source monitoring assembly 2, the lighting assembly 1 judges the accuracy of the adjustment of the workpiece moving assembly 3 according to the first light spot position monitored by the light source monitoring assembly 2, and the accuracy of the adjustment of the second light spot position is improved through the cooperation of the lighting assembly 1 and the workpiece moving assembly 3.

[0129] As shown in Figure 4 In a feasible implementation, the optical system of the light beam focusing assembly 13 is a reverse telephoto system, and the light beam focusing assembly 13 comprises a focusing lens barrel support, a focusing lens barrel and a plurality of focusing lenses; the focusing lens barrel is arranged on the focusing lens barrel support; and the plurality of focusing lenses are arranged in the focusing lens barrel.

[0130] In this technical solution, the focusing lenses are fixed in the focusing lens barrel, the focusing lens barrel is fixed on the focusing lens barrel support, and the focusing lenses form a reverse telephoto optical system, which can focus the second light beam to form a sub-millimeter light spot on the workpiece 6, thereby increasing the light spot energy density and helping to improve the detection resolution of the workpiece 6; at the same time, the focusing lenses form a reverse telephoto optical system, which can expand the working distance, and is more conducive to the spatial arrangement of the inclined illumination system.

[0131] In some examples, four focusing lenses are coaxially arranged in the focusing lens barrel to form a reverse telephoto optical system.

[0132] As shown in Figure 5 In a feasible implementation, the light source monitoring assembly 2 comprises a light source monitoring mirror group assembly 21 and a light source monitoring detector assembly 22, and the light source monitoring detector assembly 22 is arranged on the light exit side of the light source monitoring mirror group assembly 21.

[0133] In this technical solution, the first light beam forms a light spot on the light source monitoring mirror group assembly 21, and the light spot position on the light source monitoring mirror group assembly 21 is monitored by the light source monitoring detector assembly 22.

[0134] Further, the light source monitoring detector assembly 22 comprises a monitoring detector and a monitoring detector support, the monitoring detector is used for monitoring the first light beam and the light spot formed by the first light beam, and the monitoring detector support fixes the monitoring detector.

[0135] As shown in Figure 5 In a feasible implementation, the optical system of the light source monitoring mirror group assembly 21 is a long-focus focusing system, and the light source monitoring mirror group assembly 21 comprises a monitoring lens barrel support 211, a monitoring lens barrel 212 and a plurality of monitoring lenses 213; the monitoring lens barrel 212 is arranged on the monitoring lens barrel support 211; and the plurality of monitoring lenses 213 are arranged in the monitoring lens barrel 212.

[0136] In this technical solution, the monitoring lenses 213 are fixed in the monitoring lens barrel 212, the monitoring lens barrel 212 is fixed on the monitoring lens barrel support 211, and the monitoring lenses 213 form a focusing optical system to focus the first light beam on the light source monitoring detector assembly 22, thereby improving the monitoring resolution of the light source monitoring detector assembly 22 through long-focus design, and the accuracy of monitoring the position of the first light spot is improved.

[0137] In some examples, four monitoring lenses 213 are coaxially arranged in the monitoring lens barrel 212 to form a focusing optical system.

[0138] As shown in Figure 6 In a feasible implementation, the workpiece moving assembly 3 is provided with a workpiece to be measured 6, and the workpiece moving assembly 3 is used for moving the workpiece to be measured 6; the workpiece moving assembly 3 comprises a base 31, a second adjusting mechanism 32 and a rotating mechanism 33; the second adjusting mechanism 32 is electrically connected with the signal control assembly 5, and the second adjusting mechanism 32 is arranged on the base 31; the rotating mechanism 33 is electrically connected with the signal control assembly 5, and the rotating mechanism 33 is arranged on a moving table of the second adjusting mechanism 32, and the rotating mechanism 33 comprises a rotating table, and the workpiece to be measured 6 is arranged on the rotating table.

[0139] In this technical solution, the workpiece to be measured 6 is a workpiece to be detected, the second light beam is focused on the workpiece to be measured 6 and forms a second light spot, the workpiece moving assembly 3 drives the workpiece to be measured 6 to move to change the position of the second light spot on the workpiece to be measured 6, that is, to change the illumination position of the workpiece to be measured 6, the workpiece to be measured 6 is arranged on the rotating table of the rotating mechanism 33, the rotating mechanism 33 is arranged on the second adjusting mechanism 32, and the signal control assembly 5 is electrically connected with the second adjusting mechanism 32 and the rotating mechanism 33 at the same time, the second adjusting mechanism 32 is controlled to move by the signal control assembly 5 to drive the rotating mechanism 33 and the workpiece to be measured 6 to move, the rotating table is controlled to rotate by the signal control assembly 5 to drive the workpiece to be measured 6 to rotate, so as to adjust the position and angle of the workpiece to be measured 6, thereby enabling the second light spot to illuminate the specified position of the workpiece to be measured 6 without adjusting the illumination assembly 1.

[0140] In some examples, the second adjustment mechanism 32 is connected with the base 31 through a displacement shaft, so that the second adjustment mechanism 32 can move relative to the base 31, and the rotating table is connected with the second adjustment mechanism 32 through a rotating shaft, so as to carry the to-be-detected piece 6 and provide corresponding movement for detection of the to-be-detected piece 6, and full automatic detection of the to-be-detected piece 6 can be realized.

[0141] Further, the displacement shaft can be a multi-dimensional motion shaft, or can be a one-dimensional motion shaft.

[0142] As shown in Figure 7 a feasible implementation, the reflection monitoring assembly 4 includes a reflection monitoring mirror group assembly 41, a reflection monitoring turning mirror assembly 42, and a reflection monitoring detector assembly 43. The reflection monitoring turning mirror assembly 42 is arranged on the light exit side of the reflection monitoring mirror group assembly 41, and the reflection monitoring detector assembly 43 is arranged on the light exit side of the reflection monitoring turning mirror assembly 42.

[0143] In this technical solution, the second light beam is reflected on the to-be-detected piece 6 to form a third light beam, the third light beam forms a light spot on the reflection monitoring mirror group assembly 41 and enters the reflection monitoring detector assembly 43 after being reflected by the reflection monitoring turning mirror assembly 42, so as to reduce the overall length of the stabilizing system, and then the position of the light spot on the reflection monitoring mirror group assembly 41 is monitored by the reflection monitoring detector assembly 43, that is, the position of the light spot on the to-be-detected piece 6 is monitored.

[0144] As shown in Figure 7 a feasible implementation, the optical system of the reflection monitoring mirror group assembly 41 is a long-focus focusing system, and the reflection monitoring mirror group assembly 41 includes a reflection monitoring lens barrel support 411, a reflection monitoring lens barrel support 412, and a plurality of reflection monitoring lenses 413. The reflection monitoring lens barrel support 412 is arranged on the reflection monitoring lens barrel support 411, and the plurality of reflection monitoring lenses 413 are arranged in the reflection monitoring lens barrel support 412.

[0145] In this technical solution, the reflection monitoring lenses 413 are fixed in the reflection monitoring lens barrel support 412, the reflection monitoring lens barrel support 412 is fixed on the reflection monitoring lens barrel support 411, and the reflection monitoring lenses 413 form a long-focus focusing optical system to focus the third light beam on the reflection monitoring detector assembly 43, so as to realize high-resolution detection of the to-be-detected piece 6 through long-focus design.

[0146] In some examples, six reflection monitoring lenses 413 are coaxially arranged in the reflection monitoring lens barrel support 412 to form a collimating beam-reducing optical system. As shown in Figure 9 According to the second aspect of the present application, a wafer illumination light beam stabilizing method is provided, which uses the wafer illumination light beam stabilizing system according to any one of the above technical solutions to detect a wafer, including:

[0147] The lighting assembly splits the light source beam into a first beam and a second beam, focuses the second beam onto the test piece mounted on the workpiece moving assembly and reflects it to form a third beam, and reflects the third beam into the reflection monitoring assembly to form a light spot;

[0148] Obtain the first initial position of the light spot monitored by the reflection monitoring component;

[0149] The position of the light spot before adjustment is acquired by the light reflection monitoring component;

[0150] Based on the first pre-adjustment position and the first initial position recorded by the reflection monitoring component, the first offset of the light spot monitored by the reflection monitoring component is obtained;

[0151] The workpiece moving component is adjusted based on the first offset of the light spot monitored by the reflection monitoring component.

[0152] The wafer illumination beam stabilization method provided in this application involves a light source beam incident on an illumination assembly. After reflection and refraction by the illumination assembly, the beam is split into two beams. The second beam forms a second spot on the workpiece under test (DUT) on the workpiece moving assembly, illuminating the DUT. The second beam is reflected on the surface of the DUT to form a third beam, which enters the reflection monitoring assembly and forms a third spot. The light source monitoring assembly monitors the position of the second spot on the DUT by monitoring the third spot. The signal control assembly compares the position of the third spot collected by the reflection monitoring assembly with the corresponding first initial position and calculates the adjustment amount of the workpiece moving assembly. Then, it controls the workpiece moving assembly to move. Without adjusting the position and incident angle of the light source beam, the designated area of ​​the DUT can be illuminated, ensuring that defects at designated locations on the DUT can be observed through the objective lens during defect detection, thus ensuring the efficiency and continuity of defect detection.

[0153] It should be noted that the first initial position is the preset standard position of the stabilization system, and the first position before adjustment is the position of the light spot collected by the reflection monitoring component when the test piece is installed on the workpiece moving component.

[0154] In one feasible implementation, the first offset of the light spot monitored by the reflection monitoring component is obtained based on the first pre-adjustment position and the first initial position recorded by the reflection monitoring component, the steps including:

[0155] Based on the first pre-adjustment position and the first initial position recorded by the reflection monitoring component, the angular offset Δθ of the light source beam in the X direction is obtained. x Angular offset Δθ of the light source beam in the Y direction Y Obtain the surface angle of the test piece in the X direction. Surface angle of the test piece in the Y direction

[0156] The first offset amount AT of the light spot monitored by the reflection monitoring assembly in the X direction is calculated according to the following formula relationship x The first offset amount AT of the light spot monitored by the reflection monitoring assembly in the Y direction Y :

[0157]

[0158] Wherein, the angle offset amount of the light source light beam in the X direction is Δθ x The angle offset amount of the light source light beam in the Y direction is Δθ Y The surface angle of the measured object in the X direction is θ The surface angle of the measured object in the Y direction is θ The adjustment amount of the light spot of the second light beam on the measured object in the Z direction is ΔZ, F x F Y G, H x H Y Are known corresponding system parameter coefficients.

[0159] In the technical scheme, the calculation method of the offset amount of the third light spot monitored by the reflection monitoring assembly in the X and Y directions is given, the offset amount of the third light spot monitored by the reflection monitoring assembly in the X and Y directions is calculated according to the first light beam angle offset amount monitored by the light source monitoring assembly and the surface angle of the measured object, and the data acquisition is convenient and the calculation is simple.

[0160] It should be noted that the values of F x F Y G, H x H Y Can be constants.

[0161] In a feasible implementation, the third light beam is reflected into the reflection monitoring assembly to form a light spot, and then the method further comprises:

[0162] When detecting for the first time, after installing the measured object, the position of the light spot monitored by the reflection monitoring assembly is adjusted by adjusting the illumination assembly;

[0163] When continuously detecting, after replacing the measured object, the position of the light spot monitored by the reflection monitoring assembly is adjusted by adjusting the illumination assembly and / or the workpiece moving assembly.

[0164] In the technical scheme, when detecting the first measured object, the illumination assembly is moved by the signal control assembly to quickly move the second light spot to the specified position of the measured object, simplifying the operation; when replacing the measured object, the position of the light spot monitored by the reflection monitoring assembly is adjusted by adjusting the workpiece illumination assembly and / or the moving assembly, ensuring the accuracy of the illumination position.

[0165] As a preferred solution, when the workpiece size is consistent and multiple workpieces need to be continuously detected, the position of the illumination assembly can be kept unchanged, and only the position of the workpiece is adjusted by the workpiece moving assembly, which is simple and convenient, and is conducive to improving the efficiency of continuous detection of the workpiece.

[0166] In a feasible implementation, the adjusting the workpiece moving assembly further includes:

[0167] When the first offset between the first adjusted position and the first initial position monitored by the reflection monitoring assembly is greater than the preset value, the signal control assembly at least controls the workpiece moving assembly to move;

[0168] When the first offset between the first adjusted position and the first initial position monitored by the reflection monitoring assembly is not greater than the preset value, the illumination assembly and the workpiece moving assembly stop moving.

[0169] In this technical solution, when the signal control assembly calculates that the offset between the first adjusted position of each light spot and the corresponding first initial position is greater than the preset value, the second light spot is separated from the specified position of the workpiece, the signal control assembly controls the illumination assembly and / or the workpiece moving assembly to move, so that the second light spot is located at the specified position of the workpiece; when the signal control assembly calculates that the offset between the first adjusted position of each light spot and the corresponding first initial position is less than or equal to the preset value, the second light spot does not separate from the specified position of the workpiece, the signal control assembly does not send a control signal, and the illumination assembly and the workpiece moving assembly do not move, which reduces the invalid operation of the system and enables direct defect detection, thereby improving the continuity of detection.

[0170] In a feasible implementation, when the wafer illumination light beam stabilizing system includes a light source monitoring assembly, the step of adjusting the workpiece moving assembly according to the first offset of the light spot monitored by the reflection monitoring assembly includes:

[0171] Recording the second initial position of the light spot monitored by the light source monitoring assembly, and collecting the second adjusted position of the light spot monitored by the light source monitoring assembly;

[0172] According to the second adjusted position and the second initial position recorded by the light source monitoring assembly, obtaining the second offset of the light spot monitored by the light source monitoring assembly;

[0173] According to the first offset and the second offset, adjusting the workpiece moving assembly and / or the illumination assembly.

[0174] In this technical solution, when the wafer illumination beam stabilization system includes a light source monitoring component, the light beam emitted from the light source is refracted and reflected by the illumination component itself to form two beams. The first beam is received by the light source monitoring component and forms a first light spot on the light source monitoring component. The light source monitoring component monitors the position of the first light spot. The signal control component monitors whether the illumination component and the workpiece movement component are working properly based on the position information of the first light spot emitted by the light source monitoring component. That is, the light source monitoring component monitors whether the adjustment of the illumination component and the workpiece movement component is accurate and effective, and feeds back to the signal control component. The signal control component calculates the adjustment amount of the workpiece movement component and the illumination component by calculating the comprehensive information of the light source monitoring component and the reflection monitoring component, and transmits the corresponding control signal to control the movement of the workpiece movement component and / or the illumination component, so that the system has a self-monitoring function and ensures the accuracy of the second light spot position adjustment.

[0175] In one feasible implementation, the signal control component calculates and adjusts the lighting component and the workpiece moving component based on the offset.

[0176] In this technical solution, the signal control component calculates and adjusts the lighting component and the workpiece moving component based on the offset of the light spot. When the offset is less than the adjustment threshold, the lighting conditions are highly consistent, and neither the lighting component nor the workpiece moving component needs to move, thereby reducing the invalid actions of the system and improving the detection efficiency.

[0177] In one feasible implementation, the second offset of the light spot monitored by the light source monitoring component is obtained based on the second pre-adjustment position and the second initial position recorded by the light source monitoring component, the steps including:

[0178] Based on the second pre-adjustment position and the second initial position recorded by the light source monitoring component, the angular offset Δθ of the light source beam in the X direction is obtained. x Angular offset Δθ of the light source beam in the Y direction Y Obtain the position offset Δω of the light source beam in the X direction. x The positional offset Δω of the light source beam in the Y direction Y ;

[0179] The second offset ΔU of the light spot monitored by the light source monitoring component in the X direction is calculated according to the following formula. x The second offset ΔU in the Y direction Y :

[0180] ΔU x =A x Δθ x +B x Δω x ;

[0181] ΔUY = A Y Δθ Y + B Y Δω Y ;

[0182] wherein, Δθ x is the angle offset of the light source light beam in the X direction, Δθ Y is the angle offset of the light source light beam in the Y direction, Δω x is the position offset of the light source light beam in the X direction, Δω Y is the position offset of the light source light beam in the Y direction, A x , A Y , B x , B Y are known corresponding system parameter coefficients.

[0183] In the technical scheme, the calculation manner of the offset of the first light spot in the X and Y directions monitored by the light source monitoring assembly is given, and the offset of the first light spot in the X and Y directions is calculated through the first light beam angle offset and the first light beam position offset monitored by the light source monitoring assembly, so that the calculation is more accurate.

[0184] It should be noted that the values of A x , A Y , B x , B Y may be constants.

[0185] In a feasible implementation, adjusting the workpiece moving assembly and / or the lighting assembly according to the first offset and the second offset comprises:

[0186] The adjustment amount ΔX of the light spot on the surface of the workpiece to be measured in the X direction, the adjustment amount ΔY in the Y direction, and the adjustment amount ΔZ in the Z direction are calculated according to the following formula relationship:

[0187]

[0188] wherein, ΔX is the adjustment amount of the light spot on the surface of the workpiece to be measured in the X direction, ΔY is the adjustment amount in the Y direction, and ΔZ is the adjustment amount of the light spot of the second light beam on the surface of the workpiece to be measured in the Z direction, ΔT x is the first offset of the light spot in the X direction monitored by the reflection monitoring assembly, ΔT Y is the first offset of the light spot in the Y direction monitored by the reflection monitoring assembly, ΔU x is the second offset of the light spot in the X direction monitored by the light source monitoring assembly, ΔU Y is the second offset of the light spot in the X direction monitored by the light source monitoring assembly, Δθ x is the angle offset of the light source light beam in the X direction, C x , CY , D, F x , G is a known corresponding system parameter coefficient.

[0189] In the technical solution, the calculation method of the adjustment amount of the second light spot in the X, Y and Z directions on the workpiece is given, the second offset obtained by the reflection monitoring assembly and the light source monitoring assembly is monitored, and the adjustment amount of the second light spot in the X, Y and Z directions on the workpiece is comprehensively calculated, so that the accuracy of the calculation result of the adjustment amount is improved, and it is ensured that the specified position of the workpiece can be accurately highlighted by the second light spot after adjustment.

[0190] It should be noted that the value of C x , C Y , D, F x may be a constant.

[0191] In a feasible implementation, before adjusting the workpiece moving assembly and / or the lighting assembly, the following steps are included:

[0192] The allowable variation I x of the light spot in the X direction on the workpiece Y , the allowable variation I x of the light spot in the Y direction on the workpiece x , the workpiece moving assembly and / or the lighting assembly are adjusted when the following formula relationship is satisfied:

[0193]

[0194] Wherein, I Y is the allowable variation of the light spot in the X direction on the workpiece, I x is the allowable variation of the light spot in the Y direction on the workpiece, Δθ Y is the angle offset of the light source beam in the X direction, Δθ x is the angle offset of the light source beam in the Y direction, is the surface angle of the workpiece in the X direction, is the surface angle of the workpiece in the Y direction, ΔZ is the adjustment amount of the light spot of the second light beam in the Z direction on the workpiece, C Y , D, E x , E Y is a known corresponding system parameter coefficient.

[0195] It should be noted that the value of C x , C Y , D, E x , E Y may be a constant.

[0196] In the technical solution, the allowable variation of the second light spot on the workpiece is X-direction offset ΔX≤I x , Y-direction offset ΔY≤I Y , so as to obtain the adjustment condition of the lighting assembly and the workpiece moving assembly, when the deviation is less than or equal to the adjustment threshold, the lighting assembly and the workpiece moving assembly are not adjusted, when the deviation is greater than the adjustment threshold, the lighting assembly or the workpiece moving assembly is adjusted, and the second light spot is located at the specified position of the workpiece.

[0197] Further, the adjustment threshold of the second light spot on the workpiece is determined according to the ratio of the area of the second light spot to the upper surface area of the workpiece.

[0198] In a feasible implementation, after adjusting the workpiece moving assembly and / or the lighting assembly, the following steps are further included:

[0199] The adjusted position of the light spot monitored by the reflection monitoring assembly is collected, and the third offset of the light spot monitored by the reflection monitoring assembly after adjustment is obtained according to the adjusted position recorded by the reflection monitoring assembly and the first initial position;

[0200] According to the third offset, it is judged whether the lighting assembly and / or the workpiece moving assembly need to be continuously adjusted.

[0201] In the technical solution, after the position of the lighting assembly and / or the workpiece moving assembly is adjusted, the positions of the light spots are re-monitored and collected, that is, the adjusted positions of the light spots, so as to judge whether the second light spot illuminates the specified position of the workpiece, if the second light spot is still not located at the specified position of the workpiece, the adjustment amount is continuously calculated, the position of the lighting assembly and / or the workpiece moving assembly is adjusted, and the above operation is repeated until the second light spot is located at the specified position of the workpiece.

[0202] In a feasible implementation, before adjusting the workpiece moving assembly, the following steps are further included:

[0203] When the third offset between the adjusted position collected by the reflection monitoring assembly and the first position before adjustment is greater than a preset value, the signal control assembly at least controls the workpiece moving assembly to move;

[0204] When the third offset between the adjusted position collected by the reflection monitoring assembly and the first position before adjustment is not greater than the preset value, the lighting assembly and the workpiece moving assembly stop moving.

[0205] In the technical solution, when the signal control component calculates that the offset between the adjusted position of each light spot and the corresponding first pre-adjusted position is greater than the preset value, the second light spot is still away from the specified position of the workpiece after adjustment, the signal control component continues to control the lighting component and / or the workpiece moving component to move so that the second light spot is located at the specified position of the workpiece; when the signal control component calculates that the offset between the adjusted position of each light spot and the corresponding first pre-adjusted position is less than or equal to the preset value, the second light spot has been adjusted to the specified position of the workpiece, the signal control component does not send a control signal, and the lighting component and the workpiece moving component do not move, thereby reducing invalid operation of the system and facilitating continuous detection.

[0206] It can be understood that the wafer illumination light beam stabilizing method provided by the embodiments of the present application has all the beneficial effects of the wafer illumination light beam stabilizing system of the above technical solutions because it is applied to the wafer illumination light beam stabilizing system of any of the above technical solutions.

[0207] Embodiments:

[0208] The wafer defect detection focusing work process is as follows:

[0209] (1) Record the initial positions of the light spots

[0210] The initial position of the second light spot on the workpiece is recorded, that is, the initial position of the second light beam focused on the workpiece by the light source light beam is X0, Y0 and Z0, and the initial angle of the corresponding fast mirror lens is θ x0 、θ Y0 , the initial position is ω x0 、ω Y0 (by system simulation analysis, the influence can be ignored, and the analysis is later), the initial position of the first light spot in the light source monitoring component is recorded, that is, the initial position of the first light beam in the light spot in the light source monitoring component is U X0 、U Y0 , and the initial angle of the workpiece surface is recorded (by system simulation analysis, the influence can be ignored, and the analysis is later), and the initial position of the third light spot in the reflection monitoring component is recorded as T X0 、T Y0 .

[0211] (2) Collect the pre-adjusted positions of the light spots

[0212] At a certain moment, when the second light spot position formed by the second light beam converging to the surface of the workpiece is offset due to changes in the light source light beam in the stabilizing system or replacement of the workpiece, the reflection monitoring component collects the pre-adjusted position of the second light spot on the workpiece as X1, Y1 and Z1, and the pre-adjusted angle of the corresponding fast mirror lens is θ x1 、θ Y1The light source monitoring assembly collects the first light spot position U before adjustment X1 , The reflection monitoring assembly collects the third light spot position T before adjustment Y1 , The reflection monitoring assembly collects the third light spot position T before adjustment X1 , The reflection monitoring assembly collects the third light spot position T before adjustment Y1 .

[0213] The difference between each light spot position before adjustment and the corresponding initial position is calculated. If the light spot position before adjustment and the corresponding initial position are not out of tolerance, the illumination assembly and the workpiece moving assembly are adjusted. If the light spot position before adjustment and the corresponding initial position are out of tolerance, the tolerance is calculated:

[0214] The first light beam incident angle change amount of the light source light beam can be calculated from U X1 , The first light beam incident angle change amount of the light source light beam can be calculated from U Y1 , The first light beam incident angle change amount of the light source light beam can be calculated from U x , The first light beam incident angle change amount of the light source light beam can be calculated from U x , The first light beam incident angle change amount of the light source light beam can be calculated from U x , The first light beam incident angle change amount of the light source light beam can be calculated from U x1 , The first light beam incident angle change amount of the light source light beam can be calculated from U x0 , The first light beam incident angle change amount of the light source light beam can be calculated from U Y , The first light beam incident angle change amount of the light source light beam can be calculated from U Y , The first light beam incident angle change amount of the light source light beam can be calculated from U Y , The first light beam incident angle change amount of the light source light beam can be calculated from U Y1 , The first light beam incident angle change amount of the light source light beam can be calculated from U Y0 , The first light beam incident angle change amount of the light source light beam can be calculated from U

[0215] The second light spot Z-axis displacement amount ΔT can be calculated from T X1 , The second light spot Z-axis displacement amount ΔT can be calculated from T Y1 , The second light spot Z-axis displacement amount ΔT can be calculated from T x , The second light spot Z-axis displacement amount ΔT can be calculated from T Y , The second light spot Z-axis displacement amount ΔT can be calculated from T x , The second light spot Z-axis displacement amount ΔT can be calculated from T x , The second light spot Z-axis displacement amount ΔT can be calculated from T x , The second light spot Z-axis displacement amount ΔT can be calculated from T x1 , The second light spot Z-axis displacement amount ΔT can be calculated from T x0 , The second light spot Z-axis displacement amount ΔT can be calculated from T Y , The second light spot Z-axis displacement amount ΔT can be calculated from T Y , The second light spot Z-axis displacement amount ΔT can be calculated from T Y , The second light spot Z-axis displacement amount ΔT can be calculated from T Y1 , The second light spot Z-axis displacement amount ΔT can be calculated from T Y0 , The second light spot Z-axis displacement amount ΔT can be calculated from T The angle offset amount of the first light beam in the Y direction is the same as the angle offset amount of the second light spot in the Y direction.

[0216] (3) Adjusting the light source light beam with the fast mirror lens

[0217] The offset amount of the second light spot on the surface of the workpiece to be measured is ΔX=C x Δθ x +DΔZ and ΔY=C Y Δθ Y .

[0218] If the second light spot position is kept unchanged, the actual fast mirror lens angle adjustment amount can be obtained Δθ Yc = Δθ Y After adjustment, the calculation can be obtained that the spot position in the light source monitoring assembly is U xc = U x1 + A x Δθ xc , U Yc = U Y1 + A Y Δθ Yc , and the spot position in the reflection monitoring assembly is T xc = T x1 + F x Δθ xc , T Yc = T Y1 + F Y Δθ Yc .

[0219] (4) Collect the adjusted positions of the spots again

[0220] After adjustment, the spot position in the light source monitoring assembly is U X2 , U Y2 , and the spot position in the reflection monitoring assembly is T X2 , T Y2 . At this time, if the stable system limits the laser spot offset to be not greater than 2 um in the X and Y directions, then the corresponding

[0221]

[0222] In the stable system, through optical system design and simulation, the angle quantity unit is urad, the position quantity unit is um, and the corresponding parameters are A x = -6.97072 x 10 -4 , A y = -6.976993 x 10 -4 , F x = -2.78618 x 10 -3 , F y = -2.75276 x 10 -3 , G = 34.5520, C x = -6.04338 x 10 -4 , C y = -1.56174 x 10 -4 , and D = 3.738.

[0223] That is, U x2 - U x0 ≤ 2.3 um;

[0224] U Y2 - U Y0 ≤ 8.94 um;

[0225] T x2 -T x0 ≤ 9.22um;

[0226] T Y2 -T Y0 ≤ 35.2um;

[0227] If the calibration deviation is greater than the adjustment threshold setting, the measured U X2 , U Y2 , T X2 , T Y2 are brought into step (2) of U X1 , U Y1 , T X1 , T Y1 Repeat the calibration adjustment step.

[0228] Since the illumination assembly and the light source monitoring assembly in the system are stable systems, through zemax simulation, it can be known that the light source beam optical axis is translated by ω x1 = 0.1mm in the X direction, corresponding to the second spot on the measured piece offset by 0.197um; corresponding to the third spot on the reflection monitoring assembly offset by 0.325um. The light source beam optical axis is translated by ω Y1 = 0.1mm in the Y direction, corresponding to the second spot on the measured piece offset by 0.048um; corresponding to the third spot on the reflection monitoring assembly offset by 0.146um. Relative to the adjustment threshold set by the system, it is small by an order of magnitude, and the influence is small and can be ignored.

[0229] Similarly, the wafer rotation table surface generally needs to be leveled, and after leveling, the edge height difference of the rotation table surface rotating one round is about 10um. When the rotation table carries a 12-inch wafer with a diameter of 304.8mm, the corresponding angle deviation of the measured piece is Similarly, corresponding to the third spot on the reflection monitoring assembly offset by 0.106um in the X direction and 0.417um in the Y direction. Relative to the adjustment threshold set by the system, it is small by an order of magnitude, and the influence is small and can be ignored.

[0230] It is easy for those skilled in the art to understand that the above advantageous modes can be freely combined and superimposed without conflict.

[0231] The above merely preferred embodiments of the present application are not used to limit the present application, any modification, equivalent replacement and improvement made within the spirit and principle of the present application should be included in the protection scope of the present application. The above is merely the preferred embodiment of the present application, it should be pointed out that, for the ordinary skilled in the art, without departing from the technical principle of the present application, a number of improvements and variations can be made, these improvements and variations should also be considered as the protection scope of the present application.

Claims

1. A wafer illumination beam stabilization system, wherein the wafer illumination beam stabilization system is mounted on a platform, characterized in that, The wafer illumination light beam stabilizing system comprises: an illumination assembly which refracts a light source light beam to form at least a first light beam and a second light beam, the illumination assembly being adjustably arranged on the platform to adjust the light splitting angle of the light source light beam; a workpiece moving assembly for moving a workpiece to be tested which receives the second light beam and can reflect a third light beam; a reflection monitoring assembly for monitoring a light spot formed by the third light beam; a signal control assembly for controlling the movement of the workpiece moving assembly, the signal control assembly receiving a detection signal from the reflection monitoring assembly, and the signal control assembly transmitting a control signal to the workpiece moving assembly according to at least the detection signal from the reflection monitoring assembly; a light source monitoring assembly which receives the first light beam and monitors a light spot formed by the first light beam.

2. The wafer illumination light beam stabilizing system according to claim 1, wherein: the illumination assembly comprises a light beam adjusting assembly, a prism assembly and a light beam focusing assembly, the light beam adjusting assembly reflects the light source light beam onto the prism assembly, the prism assembly splits the light to form the first light beam and the second light beam, and the second light beam enters the light beam focusing assembly; the light beam adjusting assembly is adjustably arranged on the platform to adjust the angle of the first light beam and the second light beam.

3. The wafer illumination light beam stabilizing system according to claim 2, wherein: the light beam adjusting assembly comprises: a fast mirror seat; an adjusting system which is electrically connected to the signal control assembly, the adjusting system comprising a first adjusting mechanism, the adjusting system being arranged on the fast mirror seat; a fast mirror lens which is arranged on the first adjusting mechanism.

4. The wafer illumination light beam stabilizing system according to claim 2, wherein: the optical system of the light beam focusing assembly is a reverse telephoto system, and the light beam focusing assembly comprises: a focusing lens barrel support; a focusing lens barrel which is arranged on the focusing lens barrel support; a plurality of focusing lenses which are arranged in the focusing lens barrel.

5. The wafer illumination light beam stabilizing system according to claim 1, wherein: the workpiece moving assembly is provided with the workpiece to be tested, and the workpiece moving assembly is used to move the workpiece to be tested; the workpiece moving assembly comprises: a base; a second adjusting mechanism which is electrically connected to the signal control assembly, the second adjusting mechanism being arranged on the base; a rotating mechanism which is electrically connected to the signal control assembly, the rotating mechanism being arranged on a moving table of the second adjusting mechanism, and the rotating mechanism comprising a rotating table on which the workpiece to be tested is arranged.

6. The wafer illumination light beam stabilizing system according to claim 1, wherein: The reflection monitoring assembly comprises a reflection monitoring mirror group assembly, a reflection monitoring turning mirror assembly and a reflection monitoring detector assembly, the reflection monitoring turning mirror assembly is arranged on the light exit side of the reflection monitoring mirror group assembly, and the reflection monitoring detector assembly is arranged on the light exit side of the reflection monitoring turning mirror assembly.

7. The wafer illumination beam stabilizing system according to claim 6, wherein, The optical system of the reflection monitoring mirror group assembly is a long-focus focusing system, and the reflection monitoring mirror group assembly comprises: a reflection monitoring lens barrel support; a reflection monitoring lens barrel arranged on the reflection monitoring lens barrel support; a plurality of reflection monitoring lenses arranged in the reflection monitoring lens barrel.

8. The wafer illumination beam stabilizing system according to claim 1, wherein, The signal control assembly receives the detection signal of the light source monitoring assembly, and transmits a control signal to the illumination assembly according to the detection signal of the light source monitoring assembly.

9. The wafer illumination beam stabilizing system according to claim 8, wherein, The light source monitoring assembly comprises a light source monitoring mirror group assembly and a light source monitoring detector assembly, and the light source monitoring detector assembly is arranged on the light exit side of the light source monitoring mirror group assembly.

10. The wafer illumination beam stabilizing system according to claim 9, wherein, The optical system of the light source monitoring mirror group assembly is a long-focus focusing system, and the light source monitoring mirror group assembly comprises: a monitoring lens barrel support; a monitoring lens barrel arranged on the monitoring lens barrel support; a plurality of monitoring lenses arranged in the monitoring lens barrel.

11. A method of stabilizing a wafer illumination beam, the method comprising: The wafer illumination beam stabilizing system according to any one of claims 1 to 10 is used for detecting a wafer, comprising: The illumination assembly divides the light source beam into the first light beam and the second light beam, focuses the second light beam onto the to-be-detected workpiece installed on the workpiece moving assembly to form the third light beam, and reflects the third light beam into the reflection monitoring assembly to form the light spot; an initial first position of the light spot monitored by the reflection monitoring assembly is obtained; a first position before adjustment of the light spot monitored by the reflection monitoring assembly is collected; a first offset of the light spot monitored by the reflection monitoring assembly is obtained according to the first position before adjustment and the initial first position recorded by the reflection monitoring assembly; the workpiece moving assembly is adjusted according to the first offset of the light spot monitored by the reflection monitoring assembly.

12. The method of claim 11, wherein the method further comprises: The first offset of the light spot monitored by the reflection monitoring assembly is obtained according to the first position before adjustment and the initial first position recorded by the reflection monitoring assembly, and the step comprises: According to the first adjusted position recorded by the reflection monitoring assembly and the first initial position, an angle offset amount Δθ of the light source beam in the X direction is obtained x , an angle offset amount Δθ of the light source beam in the Y direction is obtained Y , a surface angle of the object to be measured in the X direction is obtained a surface angle of the object to be measured in the Y direction is obtained A first offset amount AT of the light spot monitored by the reflection monitoring assembly in the X direction is calculated according to the following formula relationship x A first offset amount AT of the light spot monitored by the reflection monitoring assembly in the Y direction is calculated according to the following formula relationship Y : wherein Δθ x is an angle offset of the light source beam in the X direction, Δθ Y is an angle offset of the light source beam in the Y direction, is a surface angle of the object under test in the X direction, is a surface angle of the object under test in the Y direction, ΔZ is an adjustment amount of the spot of the second light beam on the object under test in the Z direction, F x , F Y , G, H x , H Y are known corresponding system parameter coefficients.

13. The method of claim 11, wherein the method further comprises: After the third light beam is reflected into the reflection monitoring assembly to form the light spot, the method further comprises: When detecting for the first time, the position of the light spot monitored by the reflection monitoring assembly is adjusted by adjusting the illumination assembly after the to-be-detected workpiece is installed; When continuously detecting, the position of the light spot monitored by the reflection monitoring assembly is adjusted by adjusting the illumination assembly and / or the workpiece moving assembly after the to-be-detected workpiece is replaced.

14. The method of claim 11, wherein the method further comprises: The step of adjusting the workpiece moving assembly further comprises: When the first offset is greater than a preset value, the signal control assembly at least controls the workpiece moving assembly to move; When the first offset is not greater than the preset value, the illumination assembly and the workpiece moving assembly stop moving.

15. The method of claim 11, wherein the method further comprises: When the wafer illumination light beam stabilizing system further comprises a light source monitoring assembly, the step of adjusting the workpiece moving assembly according to the first offset of the light spot monitored by the reflection monitoring assembly comprises: recording a second initial position of the light spot monitored by the light source monitoring assembly; acquiring a second pre-adjustment position of the light spot monitored by the light source monitoring assembly; obtaining a second offset of the light spot monitored by the light source monitoring assembly according to the second pre-adjustment position and the second initial position recorded by the light source monitoring assembly; 16. The method of claim 15, wherein: adjusting the workpiece moving assembly and / or the illumination assembly according to the first offset and the second offset. According to the second adjusted position recorded by the light source monitoring assembly and the second initial position, an angle offset amount Δθ of the light source beam in the X direction is obtained x , an angle offset amount Δθ of the light source beam in the Y direction is obtained Y , a position offset amount Δω of the light source beam in the X direction is obtained x , a position offset amount Δω of the light source beam in the Y direction is obtained Y ; A second offset amount ΔU of the light spot monitored by the light source monitoring assembly in the X direction is calculated according to the following formula relationship x A second offset amount ΔU of the light spot monitored by the light source monitoring assembly in the Y direction is calculated according to the following formula relationship Y : ΔU x = A x Δθ x + B x Δω x ; ΔU Y = A Y Δθ Y + B Y Δω Y ; wherein Δθ x is the angular offset of the light source beam in the X direction, Δθ Y is the angular offset of the light source beam in the Y direction, Δω x is the positional offset of the light source beam in the X direction, Δω Y is the positional offset of the light source beam in the Y direction, A x , A Y , B x , B Y are known corresponding system parameter coefficients.

17. The method of claim 16, wherein the method further comprises: The step of obtaining the second offset of the light spot monitored by the light source monitoring assembly according to the second pre-adjustment position and the second initial position recorded by the light source monitoring assembly comprises: The step of adjusting the workpiece moving assembly and / or the illumination assembly according to the first offset and the second offset comprises: wherein ΔX is the adjustment amount of the light spot on the surface of the object to be measured in the X direction, ΔY is the adjustment amount in the Y direction, ΔZ is the adjustment amount of the light spot of the second light beam on the object to be measured in the Z direction, and ΔT x is the first offset amount of the light spot in the X direction monitored by the reflection monitoring assembly, ΔT Y is the first offset amount of the light spot in the Y direction monitored by the reflection monitoring assembly, ΔU x is the second offset amount of the light spot in the X direction monitored by the light source monitoring assembly, ΔU Y is the second offset amount of the light spot in the X direction monitored by the light source monitoring assembly, Δθ x is the angular offset amount of the light source light beam in the X direction, A x , A Y , C x , C Y , D, F x , G, are known corresponding system parameter coefficients.

18. The method of claim 17, wherein the method further comprises: calculating the adjustment amount ΔX of the light spot on the surface of the workpiece in the X direction, the adjustment amount ΔY in the Y direction, and the adjustment amount ΔZ in the Z direction according to the following formula relationship: allowable variation I in the X direction on the workpiece x allowable variation I in the Y direction Y allowable variation I in the X direction on the workpiece x when the following formula is satisfied: wherein I x is an allowable variation of the light spot in the X direction on the object to be measured, I Y is an allowable variation of the light spot in the Y direction on the object to be measured, Δθ x is an angular offset of the light source beam in the X direction, Δθ Y is an angular offset of the light source beam in the Y direction, is a surface angle of the object to be measured in the X direction, is a surface angle of the object to be measured in the Y direction, ΔZ is an adjustment of the light spot of the second light beam in the Z direction on the object to be measured, C x , C Y , D, E x , E Y are known corresponding system parameter coefficients.

19. The method of claim 18, wherein the light beam is a wafer illumination light beam. The step of adjusting the workpiece moving assembly and / or the illumination assembly further comprises: The step of adjusting the workpiece moving assembly and / or the illumination assembly further comprises: acquiring an adjusted position of the light spot monitored by the reflection monitoring assembly, and obtaining a third offset of the light spot monitored by the reflection monitoring assembly according to the adjusted position recorded by the reflection monitoring assembly and the first initial position; 20. The method of claim 19, wherein: determining whether the illumination assembly and / or the workpiece moving assembly need to be continuously adjusted according to the third offset. The step of adjusting the workpiece moving assembly further comprises: When the third offset is greater than a preset value, the signal control assembly at least controls the workpiece moving assembly to move; When the third offset is not greater than the preset value, the illumination assembly and the workpiece moving assembly stop moving.

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