Wafer illumination light beam stabilizing system and method

Abstract

The invention provides a wafer illumination light beam stabilizing system and method, and belongs to the technical field of wafer defect detection, the wafer illumination light beam stabilizing system is characterized in that a light source light beam is refracted and reflected by an illumination assembly to form two light beams, the second light beam is emitted to a to-be-detected piece on a workpiece moving assembly, the second light beam forms a second light spot on the to-be-detected piece and reflects a third light beam, and the third light beam is emitted to the workpiece moving assembly; the third light beam is emitted to the reflection monitoring assembly to form a third light spot, and the reflection monitoring assembly monitors the position of a 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 obtains the position information of the second light spot according to the received position information of the third light spot emitted by the reflection monitoring assembly, transmits a control signal to the workpiece moving assembly, and controls the workpiece moving assembly to move, so that the second light spot can illuminate the specified position of the to-be-detected piece every time defect detection is carried out on the to-be-detected piece, and the defect detection accuracy is improved. The defect detection accuracy can be improved, the method can adapt to different defect detection modes, and the application range is wide.

Description

Technical Field

[0001] The present application belongs to the technical field of wafer defect detection, and specifically relates to a wafer illumination light beam stabilization system and method. Background Art

[0002] Active laser irradiation is used in semiconductor inspection. The laser spot is focused to a certain position on the wafer to irradiate the surface defects of the wafer. The scattered light or illuminated area is matched with the defect position on the wafer after collecting and processing the defect signal to detect the wafer defects. However, in the actual inspection process, changes in the angle and height of the wafer will affect the position where the laser spot is focused on the wafer, causing the spot to deviate from the specified position of the objective lens field of view, or even exceed the objective lens field of view, affecting the defect feedback signal, resulting in differences or even errors in the calibration of the defect position and type, and affecting the accuracy of the inspection results. Summary of the invention

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

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

[0005] A second aspect of the present application provides a wafer illumination beam stabilization method.

[0006] In view of this, according to a first aspect of an embodiment of the present application, a wafer illumination beam stabilization system is provided. The wafer illumination beam stabilization system is arranged on a platform. The wafer illumination beam stabilization system comprises:

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

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

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

[0010] The signal control component is used to control the movement of the workpiece moving component. The signal control component receives the detection signal of the reflection monitoring component. The signal control component transmits a control signal to the workpiece moving component at least according to the detection signal of the reflection monitoring component.

[0011] In a feasible implementation, the lighting assembly includes a beam adjustment assembly, a prism assembly and a beam focusing assembly, the beam adjustment assembly reflects the light source beam onto the prism assembly, the prism assembly splits the light into a first beam and a second beam, and the second beam enters the beam focusing assembly;

[0012] The beam adjustment component is adjustably arranged on the platform to adjust the angles of the first beam and the second beam.

[0013] In one possible implementation, the beam adjustment assembly includes:

[0014] Fast-reflection mirror mount;

[0015] An adjustment system, the adjustment system is electrically connected to the signal control component, the adjustment system comprises a first adjustment mechanism, and the adjustment system is arranged on the quick-reflection mirror seat;

[0016] The quick-reflecting mirror lens is arranged on the first adjusting mechanism.

[0017] In a feasible implementation, the optical system of the beam focusing assembly is an anti-telephoto system, and the beam focusing assembly includes:

[0018] Focusing lens barrel bracket;

[0019] A focusing lens barrel, wherein the focusing lens barrel is arranged on a focusing lens barrel bracket;

[0020] A plurality of focusing lenses are arranged in a focusing lens barrel.

[0021] In a feasible implementation manner, a workpiece to be tested is mounted on the workpiece moving assembly, and the workpiece moving assembly is used to move the workpiece to be tested;

[0022] The workpiece moving components include:

[0023] Base;

[0024] A second adjustment mechanism, the second adjustment mechanism is electrically connected to the signal control assembly, and the second adjustment mechanism is arranged on the base;

[0025] The rotating mechanism is electrically connected to the signal control assembly, and the rotating mechanism is arranged on the moving platform of the second adjustment mechanism. The rotating mechanism includes a rotating platform, and the test piece is arranged on the rotating platform.

[0026] In a feasible embodiment, the reflection monitoring component includes a reflection monitoring mirror group component, a reflection monitoring turning mirror component and a reflection monitoring detector component. The reflection monitoring turning mirror component is arranged on the light output side of the reflection monitoring mirror group component, and the reflection monitoring detector component is arranged on the light output side of the reflection monitoring turning mirror component.

[0027] In a feasible implementation, the optical system of the light source monitoring mirror assembly is a telephoto focusing system, and the reflective monitoring mirror assembly includes:

[0028] Reflection monitoring lens tube bracket;

[0029] A reflection monitoring lens barrel, wherein the reflection monitoring lens barrel is arranged on a reflection monitoring lens barrel bracket;

[0030] Reflection monitoring lens, a plurality of reflection monitoring lenses are arranged in the reflection monitoring lens barrel.

[0031] In one possible implementation, the wafer illumination beam stabilization system further includes:

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

[0033] In a feasible implementation, the signal control component receives a detection signal from the light source monitoring component, and the signal control component transmits a control signal to the lighting component according to the detection signal from the light source monitoring component.

[0034] In a feasible implementation, the light source monitoring assembly includes a light source monitoring lens assembly and a light source monitoring detector assembly, and the light source monitoring detector assembly is arranged on the light output side of the light source monitoring lens assembly.

[0035] In a feasible implementation, the optical system of the light source monitoring lens assembly is a telephoto focusing system, and the light source monitoring lens assembly includes:

[0036] Monitoring lens tube bracket;

[0037] A monitoring lens barrel, wherein the monitoring lens barrel is arranged on a monitoring lens barrel bracket;

[0038] A plurality of monitoring lenses are arranged in the monitoring lens barrel.

[0039] According to a second aspect of an embodiment of the present application, a wafer illumination beam stabilization method is proposed, and a wafer illumination beam stabilization system as in any of the above technical solutions is used to detect a wafer, including:

[0040] The lighting component divides the light beam of the light source into a first light beam and a second light beam, focuses the second light beam onto the workpiece to be tested mounted on the workpiece moving component and reflects to form a third light beam, and reflects the third light beam into the reflection monitoring component to form a light spot;

[0041] Acquire a first initial position of a light spot monitored by the reflection monitoring component;

[0042] Collecting a first pre-adjustment position of a light spot monitored by a reflection monitoring component;

[0043] According to a first pre-adjustment position and a first initial position recorded by the reflection monitoring component, a first offset of a light spot monitored by the reflection monitoring component is obtained;

[0044] The workpiece moving component is adjusted according to the first offset of the light spot monitored by the reflection monitoring component.

[0045] In a feasible implementation manner, obtaining a first offset of a light spot monitored by the reflection monitoring component according to a first pre-adjustment position and a first initial position recorded by the reflection monitoring component comprises:

[0046] According to 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 , the angular offset of the light source beam in the Y direction Δθ Y , obtain the surface angle of the test piece in the X direction Surface angle of the test piece in the Y direction

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

[0048]

[0049] Among them, 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, is the surface angle of the test piece in the X direction, is the surface angle of the DUT in the Y direction, ΔZ is the adjustment amount of the spot of the second beam on the DUT in the Z direction, and F x 、F Y , G, H x , H Y are the corresponding known system parameter coefficients.

[0050] In a feasible implementation manner, the third light beam is reflected into the reflection monitoring component to form a light spot, and then the method further includes:

[0051] During the first inspection, after the test piece is installed, the position of the light spot monitored by the reflection monitoring component is adjusted by adjusting the lighting component;

[0052] During continuous testing, after the test piece is replaced, the position of the light spot monitored by the reflection monitoring component is adjusted by adjusting the lighting component and / or the workpiece moving component.

[0053] In a feasible implementation manner, adjusting the workpiece moving component also includes:

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

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

[0056] In a feasible implementation, when the wafer illumination beam stabilization system includes a light source monitoring component, the step of adjusting the workpiece moving component according to the first offset of the light spot monitored by the reflection monitoring component includes:

[0057] Record a second initial position of the light spot monitored by the light source monitoring component, and collect a second pre-adjustment position of the light spot monitored by the light source monitoring component;

[0058] According to the second pre-adjustment position and the second initial position recorded by the light source monitoring component, a second offset of the light spot monitored by the light source monitoring component is obtained;

[0059] The workpiece moving assembly and / or the lighting assembly are adjusted based on the first offset and the second offset.

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

[0061] According to 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 , the angular offset of the light source beam in the Y direction Δθ Y , obtain the position offset Δω of the light source beam in the X direction x , the position offset of the light source beam in the Y direction Δω Y ;

[0062] 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 :

[0063] ΔU x =A x Δθ x +B x Δω x ;

[0064] ΔU Y =A Y Δθ Y +B Y Δω Y ;

[0065] Among them, Δθ x is the angular offset of the light source beam in the X direction, Δθ Y is the angular deviation of the light source beam in the Y direction, Δω x is the position offset of the light source beam in the X direction, Δω YA is the position offset of the light source beam in the Y direction, x , A Y , B x , B Y are the corresponding known system parameter coefficients.

[0066] In a feasible 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 test piece 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:

[0068]

[0069] Wherein, ΔX is the adjustment amount of the light spot on the surface of the test piece 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 test piece in the Z direction, ΔT x is the first offset of the light spot monitored by the reflection monitoring component in the X direction, ΔT Y is the first offset of the light spot monitored by the reflection monitoring component in the Y direction, ΔU x The second offset of the light spot monitored by the light source monitoring component in the X direction, ΔU Y The second offset of the light spot monitored by the light source monitoring component in the X direction; Δθ x is the angular offset of the light source beam in the X direction, C x , C Y , D, F x , G are the known corresponding system parameter coefficients.

[0070] In a feasible embodiment, before adjusting the workpiece moving component and / or the lighting component, the method includes:

[0071] The allowable variation of the light spot in the X direction on the object to be tested I x , the allowable variation in the Y direction I Y , when the allowable variation in the X direction of the test piece is I x , adjust the workpiece moving component and / or lighting component when the following formula relationship is met:

[0072]

[0073] Among them, I x I is the allowable variation of the light spot in the X direction on the object to be tested, Y Δθ is the allowable variation of the light spot in the Y direction on the object to be tested. x is the angular offset of the light source beam in the X direction, Δθ Yis the angular offset of the light source beam in the Y direction, is the surface angle of the test piece in the X direction, is the surface angle of the DUT in the Y direction, ΔZ is the adjustment amount of the spot of the second beam on the DUT in the Z direction, C x , C Y , D, E x 、E Y are the corresponding known system parameter coefficients.

[0074] In a feasible embodiment, after adjusting the workpiece moving component and / or the lighting component, the method further comprises:

[0075] Collecting the adjusted position of the light spot monitored by the reflection monitoring component, and obtaining the adjusted third offset of the light spot monitored by the reflection monitoring component according to the adjusted position recorded by the reflection monitoring component and the first initial position;

[0076] Based on the third offset, it is determined whether it is necessary to continue adjusting the lighting assembly and / or the workpiece moving assembly.

[0077] In a feasible implementation manner, adjusting the workpiece moving component also includes:

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

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

[0080] Compared with the prior art, the wafer illumination beam stabilization system and method of the present application have the following beneficial effects:

[0081] The wafer illumination beam stabilization system provided in the embodiment of the present application includes an illumination component, a workpiece moving component, a reflection monitoring component and a signal control component. The light beam emitted by the light source beam is refracted and reflected by the illumination component itself to form two light beams. The second light beam is emitted to the workpiece to be tested on the workpiece moving component. The second light beam forms a second light spot on the workpiece to be tested and reflects a third light beam. The third light beam is emitted to the reflection monitoring component to form a third light spot. The reflection monitoring component 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 component obtains the position information of the second light spot according to the position information of the third light spot received from the reflection monitoring component, transmits a control signal to the workpiece moving component, and controls the movement of the workpiece moving component, so that each time the workpiece to be tested is subjected to defect detection, the second light spot can illuminate the specified position of the workpiece to be tested, which is beneficial to improving the accuracy of defect detection, and can adapt to different defect detection modes, and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0082] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

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

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

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

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

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

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

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

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

[0091] Fig. 9 A schematic workflow diagram of a wafer illumination beam stabilization method according to an embodiment of the present application;

[0092] in, Figures 1 to 9 The corresponding relationship between the reference numerals and component names in the figure is:

[0093] 1. Lighting component; 2. Light source monitoring component; 3. Workpiece moving component; 4. Reflection monitoring component; 5. Signal control component; 6. Part to be tested;

[0094] 11. Beam adjustment assembly; 12. Prism assembly; 13. Beam focusing assembly;

[0095] 111. quick-reflex mirror mount; 112. adjustment system; 113. quick-reflex mirror lens;

[0096] 21. Light source monitoring lens assembly; 22. Light source monitoring detector assembly;

[0097] 211. Monitoring lens barrel bracket; 212. Monitoring lens barrel; 213. Monitoring lens;

[0098] 31. base; 32. second adjustment mechanism; 33. rotation mechanism;

[0099] 41. Reflection monitoring mirror assembly; 42. Reflection monitoring deflection mirror assembly; 43. Reflection monitoring detector assembly;

[0100] 411. Reflection monitoring lens barrel bracket; 412. Reflection monitoring lens barrel; 413. Reflection monitoring lens. DETAILED DESCRIPTION

[0101] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0102] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0103] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to 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] like Figures 1 to 3 As shown, according to the first aspect of an embodiment of the present application, a wafer illumination beam stabilization system is proposed, and the wafer illumination beam stabilization system is arranged on a platform, and the wafer illumination beam stabilization system includes: an illumination component 1, a workpiece moving component 3, a reflection monitoring component 4 and a signal control component 5; the illumination component 1 refracts the light source beam to form at least a first light beam and a second light beam, and the illumination component 1 can be adjusted on the platform to adjust the splitting angle of the light source beam; the workpiece moving component 3 is used to move the test piece 6, and the test piece 6 receives the second light beam and can reflect a third light beam; the reflection monitoring component 4 is used to monitor the light spot formed by the third light beam; the signal control component 5 is used to control the movement of the workpiece moving component 3, the signal control component 5 receives the detection signal of the reflection monitoring component 4, and the signal control component 5 transmits a control signal to the workpiece moving component 3 at least according to the detection signal of the reflection monitoring component 4.

[0106] The wafer illumination beam stabilization system provided in the embodiment of the present application includes an illumination component 1, a workpiece moving component 3, a reflection monitoring component 4 and a signal control component 5. The light beam emitted by the light source is refracted and reflected by the illumination component 1 itself to form two light beams. The second light beam is emitted to the workpiece to be tested 6 on the workpiece moving component 3. The second light beam forms a second light spot on the workpiece to be tested 6 and reflects a third light beam. The third light beam is emitted to the reflection monitoring component 4 to form a third light spot. The reflection monitoring component 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 component 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 component 4, transmits a control signal to the workpiece moving component 3, and controls the movement of the workpiece moving component 3, so that each time a defect detection is performed on the workpiece to be tested 6, the second light spot can illuminate the specified position of the workpiece to be tested 6, which is beneficial to improving the accuracy of defect detection, and can adapt to different defect detection modes, and has a wide range of applications.

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

[0108] In some examples, the reflection monitoring component 4 may also be configured with an observation system, and the position of the second light spot on the wafer is directly observed by the reflection monitoring component 4 , and the observation system carried by the reflection monitoring component 4 directly performs defect detection on the wafer.

[0109] like Figure 1 to Figure 3As shown, in a feasible implementation manner, the wafer illumination beam stabilization system further includes: a light source monitoring component 2; the light source monitoring component 2 receives the first light beam, and the light source monitoring component 2 monitors a light spot formed by the first light beam.

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

[0111] like Figure 1 to Figure 3 As shown, in a feasible implementation manner, the signal control component 5 receives the detection signal of the light source monitoring component 2 , and the signal control component 5 transmits a control signal to the lighting component 1 according to the detection signal of the light source monitoring component 2 .

[0112] In this technical solution, the signal control component 5 monitors whether the lighting component 1 and the workpiece moving component 3 are working normally according to the position information of the first light spot emitted by the light source monitoring component 2, that is, the light source monitoring component 2 monitors whether the adjustment of the lighting component 1 and the workpiece moving component 3 is accurate and effective, and feeds back to the signal control component 5. The signal control component 5 calculates the comprehensive information of the light source monitoring component 2 and the reflection monitoring component 4, calculates the adjustment amount of the workpiece moving component 3 and the lighting component 1 and transmits the corresponding control signal, controls the movement of the workpiece moving component 3 and / or the lighting component 1, so that the system has a self-monitoring function, thereby ensuring the accuracy of the adjustment of the second light spot position.

[0113] It can be understood that the reflection monitoring component 4 monitors the third light spot and collects the position signal of the third light spot, the reflection monitoring component 4 transmits the position signal of the third light spot to the signal control component 5, the signal control component 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 component 3. The light source monitoring component 2 monitors the first light spot and collects the position signal of the first light spot, the light source monitoring component 2 transmits the position signal of the first light spot to the signal control component 5, and the signal control component 5 adjusts the lighting component 1 according to the position signal of the first light spot.

[0114] It is understandable that if Figure 8 The signal control component 5 is electrically connected to the lighting component 1, the light source monitoring component 2, the workpiece moving component 3, and the reflection monitoring component 4. The signal control component 5 receives the light spot position signal monitored by the light source monitoring component 2 and the reflection monitoring component 4, and after processing, the signal control component 5 sends a control signal to the lighting component 1 and / or the workpiece moving component 3.

[0115] Furthermore, the signal control component 5 is a hardware control system, which performs signal and algorithm processing to obtain the adjustment amount of the lighting component 1 and the workpiece moving component 3, and transmits the signal 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 stabilization system.

[0116] Furthermore, the piece to be tested 6 is mounted on the workpiece moving assembly 3, and the workpiece moving assembly 3 drives the piece to be tested 6 to move and / or adjust the position of the lighting assembly 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 center of mass, centroid or other geometric center of the wafer. Therefore, each time the piece to be tested 6 is replaced, the light spot where the light source light beam converges on the piece to be tested 6 can be at the specified position of the objective lens field of view, thereby improving the accuracy of the defect feedback signal, reducing the calibration differences and errors of the defect position and type, and thus improving the accuracy of the detection result.

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

[0118] In a feasible implementation, the stabilization system can also be directly used as a defect detection system to adjust the illuminated position of the light source beam on the wafer, and quickly adjust the light source beam in real time. When the stabilization system is used as a defect detection system, the reflection monitoring component 4 can be configured with a shooting camera, so that the reflection monitoring component 4 has a shooting function, and the movement of the lighting component 1 is adjusted according to the preset scanning trajectory, and the workpiece moving component 3 drives the wafer to move to maintain the second light spot to illuminate the specified position, and then the shooting camera directly observes the surface area of ​​the wafer illuminated by the light source beam, and through algorithm processing, the surface defects of the wafer are identified, and the wafer is directly observed to achieve bright field defect detection of the wafer.

[0119] It is understandable that, according to different DUTs 6 and different scanning modes, the signal control component 5 can be transmitted to the actuators in the lighting component 1 and the workpiece moving component 3 to realize the designated track scanning detection of the wafer. The light source beam scanning track and the workpiece moving component 3 cooperate with each other to realize a variety of scanning modes such as linear scanning and spiral scanning.

[0120] like Figure 4As shown, in a 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. The prism assembly 12 splits the light source beam into 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 can be adjusted on the platform to adjust the angles of the first beam and the second beam.

[0121] In this technical solution, the incident light beam of the light source is reflected by the light beam adjustment component 11 to the prism component 12, and the prism component 12 divides the light beam of the light source reflected by the light beam adjustment component 11 into two beams, wherein the first light beam is split and enters the light source monitoring component 2, and forms a first light spot on the light source monitoring component 2, and the second light beam is split and enters the light beam focusing component 13, and is focused to the surface of the device under test 6 by the light beam focusing component 13, and forms a second light spot on the surface of the device under test 6; the position of the light beam adjustment component 11 is controlled by the signal control component 5 to adjust the splitting angle of the first light beam and the second light beam, 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 device under test 6, so that the second light spot can illuminate the specified position of the device under test 6.

[0122] Furthermore, the prism assembly 12 includes a prism and a prism seat, and the prism is fixed on the prism seat.

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

[0124] like Figure 4 As shown, in a feasible implementation manner, the light beam adjustment component 11 includes: a quick-reflection mirror holder 111, an adjustment system 112 and a quick-reflection mirror lens 113; the adjustment system 112 is electrically connected to the signal control component 5, the adjustment system 112 includes a first adjustment mechanism, and the adjustment system 112 is arranged on the quick-reflection mirror holder 111; the quick-reflection mirror lens 113 is arranged on the first adjustment mechanism.

[0125] In this technical solution, the quick-reflective mirror lens 113 is arranged on the first adjustment mechanism of the adjustment system 112, and a control signal is transmitted to the adjustment system 112 through the signal control component 5, so that the first adjustment mechanism drives the quick-reflective mirror lens 113 to move, thereby changing the angles of the first light beam and the second light beam split from the light source light beam, so as to adjust the position of the first light spot formed by the first light beam in the light source monitoring component 2 and the position of the second light spot formed by the second light beam on the device to be tested 6. The position of the quick-reflective mirror lens 113 is adjusted by the signal control component 5 to ensure that the second light spot can illuminate the designated position of the device to be tested 6.

[0126] Furthermore, the adjustment system 112 may adopt a piezoelectric drive response system to quickly respond to the control signal of the signal control component 5; the quick-reflection mirror lens 113 is installed on the first adjustment mechanism, and the quick-reflection mirror lens 113 moves relative to the quick-reflection mirror lens seat 111 along with the first adjustment mechanism.

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

[0128] In some examples, when the adjustment system 112 of the lighting component 1 is electrically connected to the signal control component 5 and the first light beam is irradiated to the light source monitoring component 2, the lighting component 1 determines the accuracy of the adjustment of the workpiece moving component 3 based on the first light spot position monitored by the light source monitoring component 2, and the accuracy of the adjustment of the second light spot position is improved by the cooperation between the lighting component 1 and the workpiece moving component 3.

[0129] like Figure 4 As shown, in a feasible implementation manner, the optical system of the beam focusing assembly 13 is an anti-telephoto system, and the beam focusing assembly 13 includes: a focusing lens barrel bracket, a focusing lens barrel and a plurality of focusing lenses; the focusing lens barrel is arranged on the focusing lens barrel bracket; and a plurality of focusing lenses are arranged in the focusing lens barrel.

[0130] In this technical solution, the focusing lens is fixed in the focusing lens barrel, and the focusing lens barrel is fixed on the focusing lens barrel bracket. The focusing lens forms an anti-telephoto optical system, which can focus the second light beam to form a submillimeter light spot on the test piece 6, increase the energy density of the light spot, and help improve the detection resolution of the test piece 6. At the same time, the focusing lens forms an anti-telephoto optical system, which can expand the rear working distance and is more conducive to the spatial arrangement of the inclined lighting system.

[0131] In some examples, four coaxially arranged focusing lenses are disposed in the focusing barrel to form an anti-telephoto optical system.

[0132] like Figure 5 As shown, in a feasible implementation manner, the light source monitoring assembly 2 includes a light source monitoring lens assembly 21 and a light source monitoring detector assembly 22 , and the light source monitoring detector assembly 22 is arranged on the light emitting side of the light source monitoring lens assembly 21 .

[0133] In this technical solution, the first light beam forms a light spot on the light source monitoring lens assembly 21 , and the light source monitoring detector assembly 22 monitors the position of the light spot on the light source monitoring lens assembly 21 .

[0134] Furthermore, the light source monitoring detector assembly 22 includes a monitoring detector and a monitoring detector bracket. The monitoring detector is used to monitor the first light beam and the light spot formed therein. The monitoring detector bracket fixes the monitoring detector.

[0135] like Figure 5 As shown, in a feasible implementation, the optical system of the light source monitoring lens group assembly 21 is a telephoto focusing system, and the light source monitoring lens group assembly 21 includes: a monitoring lens barrel bracket 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 bracket 211; and a plurality of monitoring lenses 213 are arranged in the monitoring lens barrel 212.

[0136] In this technical solution, the monitoring lens 213 is fixed in the monitoring lens barrel 212, and the monitoring lens barrel 212 is fixed on the monitoring lens barrel bracket 211. The monitoring lens 213 forms a focusing optical system to focus the first light beam onto the light source monitoring detector assembly 22. The monitoring resolution of the light source monitoring detector assembly 22 is improved through the telephoto design, which is beneficial to improving the accuracy of monitoring the position of the first light spot.

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

[0138] like Figure 6 As shown, in a feasible embodiment, a workpiece to be tested 6 is installed on the workpiece moving assembly 3, and the workpiece moving assembly 3 is used to move the workpiece to be tested 6; the workpiece moving assembly 3 includes a base 31, a second adjustment mechanism 32 and a rotating mechanism 33; the second adjustment mechanism 32 is electrically connected to the signal control assembly 5, and the second adjustment mechanism 32 is arranged on the base 31; the rotating mechanism 33 is electrically connected to the signal control assembly 5, and the rotating mechanism 33 is arranged on the moving table of the second adjustment mechanism 32, the rotating mechanism 33 includes a rotating table, and the workpiece to be tested 6 is arranged on the rotating table.

[0139] In this technical solution, the piece to be tested 6 is a workpiece to be detected, the second light beam is focused on the piece to be tested 6 and forms a second light spot, the piece to be tested 6 is driven to move by the workpiece moving component 3 to change the position of the second light spot on the piece to be tested 6, that is, to change the illuminated position of the piece to be tested 6, the piece to be tested 6 is arranged on a rotating table of a rotating mechanism 33, the rotating mechanism 33 is arranged on a second adjustment mechanism 32, the signal control component 5 is electrically connected to the second adjustment mechanism 32 and the rotating mechanism 33 at the same time, the signal control component 5 controls the movement of the second adjustment mechanism 32 to drive the movement of the rotating mechanism 33 and the piece to be tested 6, the signal control component 5 controls the rotation of the rotating table to drive the piece to be tested 6 to rotate, so as to adjust the position and angle of the piece to be tested 6, so that the second light spot can illuminate the specified position of the piece to be tested 6 without adjusting the lighting component 1.

[0140] In some examples, the second adjustment mechanism 32 is connected to the base 31 via a displacement axis so that the second adjustment mechanism 32 can move relative to the base 31, and the rotating table is connected to the second adjustment mechanism 32 via a rotating axis to transport the test piece 6 and provide corresponding movement for the detection of the test piece 6, thereby realizing comprehensive automatic detection of the test piece 6.

[0141] Furthermore, the displacement axis may be a multi-dimensional motion axis, or a one-dimensional motion axis.

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

[0143] In this technical solution, the second light beam is reflected on the test piece 6 to form a third light beam, the third light beam forms a light spot on the reflection monitoring mirror assembly 41 and enters the reflection monitoring detector assembly 43 after being reflected by the reflection monitoring deflection mirror assembly 42, thereby reducing the overall length of the stabilization system. The reflection monitoring detector assembly 43 then monitors the light spot position on the reflection monitoring mirror assembly 41, that is, monitors the light spot position on the test piece 6.

[0144] like Figure 7 As shown, in a feasible implementation manner, the optical system of the light source monitoring lens group assembly 21 is a telephoto focusing system, and the reflection monitoring lens group assembly 41 includes: a reflection monitoring lens barrel bracket 411, a reflection monitoring lens barrel bracket 412 and a reflection monitoring lens 413; the reflection monitoring lens barrel bracket 412 is arranged on the reflection monitoring lens barrel bracket 411; and a plurality of reflection monitoring lenses 413 are arranged in the reflection monitoring lens barrel bracket 412.

[0145] In this technical solution, the reflection monitoring lens 413 is fixed in the reflection monitoring lens barrel bracket 412, and the reflection monitoring lens barrel bracket 412 is fixed on the reflection monitoring lens barrel bracket 411. The reflection monitoring lens 413 forms a telephoto focusing optical system to focus the third light beam onto the reflection monitoring detector assembly 43, and high-resolution detection of the test piece 6 is achieved through the telephoto design.

[0146] In some examples, six coaxially arranged reflective monitoring lenses 413 are disposed in the reflective monitoring lens barrel support 412 to form a collimated and reduced beam optical system. Fig. 9 As shown, according to the second aspect of the present application, a wafer illumination beam stabilization method is proposed, and a wafer illumination beam stabilization system as described in any one of the above technical solutions is used to detect a wafer, including:

[0147] The lighting component divides the light beam of the light source into a first light beam and a second light beam, focuses the second light beam onto the workpiece to be tested mounted on the workpiece moving component and reflects to form a third light beam, and reflects the third light beam into the reflection monitoring component to form a light spot;

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

[0149] Collecting a first pre-adjustment position of a light spot monitored by a reflection monitoring component;

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

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

[0152] Through the wafer illumination beam stabilization method provided in the embodiment of the present application, the light source beam is incident on the lighting component, and is reflected and refracted by the lighting component to be divided into two beams. The second beam forms a second light spot on the workpiece to be tested on the workpiece moving component to illuminate the workpiece to be tested. The second light beam is reflected on the surface of the workpiece to be tested to form a third light beam that enters the reflection monitoring component and forms a third light spot. The light source monitoring component monitors the position of the second light spot on the workpiece to be tested by monitoring the third light spot. The signal control component compares the collected third light spot position with the corresponding first initial position according to the reflection monitoring component and calculates the adjustment amount of the workpiece moving component, and then controls the movement of the workpiece moving component. The specified area of ​​the workpiece to be tested can be illuminated without adjusting the position and incident angle of the light source beam, ensuring that the defects at the specified position on the workpiece to be tested can be observed through the objective lens during defect detection, thereby ensuring the efficiency and continuity of defect detection.

[0153] It should be noted that the first initial position is a preset standard position of the stabilization system, and the first pre-adjustment position is the position of the light spot collected by the reflection monitoring component when the workpiece to be tested is mounted on the workpiece moving component.

[0154] In a feasible implementation manner, obtaining a first offset of a light spot monitored by the reflection monitoring component according to a first pre-adjustment position and a first initial position recorded by the reflection monitoring component comprises:

[0155] According to 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 , the angular offset of the light source beam in the Y direction Δθ 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 ΔT of the light spot monitored by the reflection monitoring component in the X direction is calculated according to the following formula: x , the first offset ΔT in the Y direction Y :

[0157]

[0158] Among them, 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, is the surface angle of the test piece in the X direction, is the surface angle of the DUT in the Y direction, ΔZ is the adjustment amount of the spot of the second beam on the DUT in the Z direction, and F x 、F Y , G, H x , H Y are the corresponding known system parameter coefficients.

[0159] In this technical solution, a method for calculating the X and Y offsets of the third light spot monitored by the reflection monitoring component is given. According to the first light beam angle offset monitored by the light source monitoring component and the surface angle of the test piece, the X and Y offsets of the third light spot monitored by the reflection monitoring component are calculated. Data acquisition is convenient and calculation is simple.

[0160] It should be noted that F x 、F Y , G, H x , H Y The value of can be a constant.

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

[0162] During the first inspection, after the test piece is installed, the position of the light spot monitored by the reflection monitoring component is adjusted by adjusting the lighting component;

[0163] During continuous testing, after the test piece is replaced, the position of the light spot monitored by the reflection monitoring component is adjusted by adjusting the lighting component and / or the workpiece moving component.

[0164] In this technical solution, when detecting the first test piece, the movement of the lighting component is controlled by the signal control component to quickly move the second light spot to the specified position of the test piece, thereby simplifying the operation; after the test piece is replaced, the position of the light spot monitored by the reflection monitoring component is adjusted by adjusting the workpiece lighting component and / or the moving component to ensure the accuracy of the illuminated position.

[0165] As a preferred solution, since the second light spot has illuminated the specified position of the first test piece, when the size consistency of the test pieces is high and multiple test pieces need to be tested continuously, the position of the lighting component can be kept unchanged, and the position of the test piece can be adjusted only by the workpiece moving component. The operation is simple and convenient, which is conducive to improving the efficiency of continuous detection of the test pieces.

[0166] In a feasible implementation manner, adjusting the workpiece moving component also includes:

[0167] When a first offset between a first pre-adjustment position and a first initial position acquired by the reflection monitoring component is greater than a preset value, the signal control component at least controls the workpiece moving component to move;

[0168] When a first offset between the first pre-adjustment position collected by the reflection monitoring component and the first initial position is not greater than a preset value, the lighting component and the workpiece moving component stop moving.

[0169] In this technical solution, when the signal control component calculates that the offset between the first pre-adjustment position of each light spot and the corresponding first initial position is greater than a preset value, the second light spot deviates from the specified position of the test piece, and the signal control component controls 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 test piece; when the signal control component calculates that the offset between the first pre-adjustment position of each light spot and the corresponding first initial position is less than or equal to a preset value, the second light spot does not deviate from the specified position of the test piece, the signal control component does not send a control signal, the lighting component and the workpiece moving component do not move, thereby reducing invalid operations of the system, allowing direct defect detection, and helping to improve the continuity of detection.

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

[0171] Record a second initial position of the light spot monitored by the light source monitoring component, and collect a second pre-adjustment position of the light spot monitored by the light source monitoring component;

[0172] According to the second pre-adjustment position and the second initial position recorded by the light source monitoring component, a second offset of the light spot monitored by the light source monitoring component is obtained;

[0173] The workpiece moving assembly and / or the lighting assembly are adjusted based on the first offset and the second offset.

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

[0175] In a feasible implementation manner, the signal control component calculates and adjusts the adjustment amount of the lighting component and the adjustment amount of the workpiece moving component according to the offset.

[0176] In this technical solution, the signal control component calculates the adjustment amount of the lighting component and the workpiece moving component according to the offset of the light spot. When the offset is less than the adjustment threshold, the lighting condition is highly consistent, and neither the lighting component nor the workpiece moving component needs to be moved, so as to reduce invalid actions of the system and help improve detection efficiency.

[0177] In a feasible implementation, according to the second pre-adjustment position and the second initial position recorded by the light source monitoring component, obtaining the second offset of the light spot monitored by the light source monitoring component comprises:

[0178] According to 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 , the angular offset of the light source beam in the Y direction Δθ Y , obtain the position offset Δω of the light source beam in the X direction x , the position offset of the light source beam in the Y direction Δω 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] Among them, Δθ x is the angular offset of the light source beam in the X direction, Δθ Y is the angular deviation of the light source beam in the Y direction, Δω x is the position offset of the light source beam in the X direction, Δω Y A is the position offset of the light source beam in the Y direction, x , A Y , B x , B Y are the corresponding known system parameter coefficients.

[0183] In this technical solution, a method for calculating the offset of the first light spot in the X and Y directions monitored by the light source monitoring component is given. The offset of the first light spot in the X and Y directions is calculated by the first light beam angle offset and the first light beam position offset monitored by the light source monitoring component, and the calculation is more accurate.

[0184] It should be noted that A x , A Y , B x , B Y The value of can be a constant.

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

[0186] The adjustment amount ΔX of the light spot on the surface of the test piece 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:

[0187]

[0188] Wherein, ΔX is the adjustment amount of the light spot on the surface of the test piece 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 test piece in the Z direction, ΔT x is the first offset of the light spot monitored by the reflection monitoring component in the X direction, ΔT Y is the first offset of the light spot monitored by the reflection monitoring component in the Y direction, ΔU x The second offset of the light spot monitored by the light source monitoring component in the X direction, ΔU Y The second offset of the light spot monitored by the light source monitoring component in the X direction, Δθ x is the angular offset of the light source beam in the X direction, C x , CY , D, F x , G are the known corresponding system parameter coefficients.

[0189] In this technical solution, a method for calculating the adjustment amount of the second light spot in the X, Y, and Z directions on the piece to be tested is given. The second offset amount obtained by monitoring the light spot through the reflection monitoring component and the light source monitoring component is used to comprehensively calculate the adjustment amount of the second light spot in the X, Y, and Z directions on the piece to be tested, thereby improving the accuracy of the adjustment amount calculation result and ensuring that the second light spot after adjustment can accurately illuminate the designated position of the piece to be tested.

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

[0191] In a feasible embodiment, before adjusting the workpiece moving component and / or the lighting component, the method includes:

[0192] The allowable variation of the light spot in the X direction on the object to be tested I x , the allowable variation in the Y direction I Y , when the allowable variation in the X direction of the test piece is I x , adjust the workpiece moving component and / or lighting component when the following formula relationship is met:

[0193]

[0194] Among them, I x I is the allowable variation of the light spot in the X direction on the object to be tested, Y Δθ is the allowable variation of the light spot in the Y direction on the object to be tested. 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, is the surface angle of the test piece in the X direction, is the surface angle of the DUT in the Y direction, ΔZ is the adjustment amount of the spot of the second beam on the DUT in the Z direction, C x , C Y , D, E x 、E Y are the corresponding known system parameter coefficients.

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

[0196] In this technical solution, the allowable variation of the second light spot on the object to be tested is the X-direction offset ΔX≤I x , the offset in the Y direction ΔY≤I Y , to obtain the adjustment conditions of the lighting component and the workpiece moving component. When the deviation is less than or equal to the adjustment threshold, the lighting component and the workpiece moving component are not adjusted. When the deviation is greater than the adjustment threshold, the lighting component or the workpiece moving component is adjusted so that the second light spot is located at the specified position of the workpiece to be tested.

[0197] Furthermore, the adjustment threshold of the second light spot on the device to be tested is determined according to the ratio of the area of ​​the second light spot to the upper surface area of ​​the device to be tested.

[0198] In a feasible embodiment, after adjusting the workpiece moving component and / or the lighting component, the method further comprises:

[0199] Collecting the adjusted position of the light spot monitored by the reflection monitoring component, and obtaining the adjusted third offset of the light spot monitored by the reflection monitoring component according to the adjusted position recorded by the reflection monitoring component and the first initial position;

[0200] Based on the third offset, it is determined whether it is necessary to continue adjusting the lighting assembly and / or the workpiece moving assembly.

[0201] In this technical solution, after adjusting the position of the lighting component and / or the workpiece moving component, the position of each light spot, that is, the adjusted position of each light spot, is re-monitored and collected to determine whether the second light spot illuminates the specified position of the workpiece to be tested. If the second light spot is still not at the specified position of the workpiece to be tested, the adjustment amount is continued to be calculated, the position of the lighting component and / or the workpiece moving component is adjusted, and the above operation is repeated until the second light spot is located at the specified position of the workpiece to be tested.

[0202] In a feasible implementation manner, adjusting the workpiece moving component also includes:

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

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

[0205] In this technical solution, when the signal control component calculates that the offset between the adjusted position of each light spot and the corresponding first position before adjustment is greater than a preset value, the second light spot is still out of the specified position of the test piece after adjustment, and the signal control component continues to control the movement of the lighting component and / or the workpiece moving component to make the second light spot located at the specified position of the test piece; when the signal control component calculates that the offset between the adjusted position of each light spot and the corresponding first position before adjustment is less than or equal to a preset value, the second light spot has been adjusted to the specified position of the test piece, the signal control component does not send a control signal, the lighting component and the workpiece moving component do not move, thereby reducing invalid operations of the system, allowing direct defect detection, and helping to improve the continuity of detection.

[0206] It can be understood that the wafer illumination beam stabilization method provided in the embodiment of the present application is applied to the wafer illumination beam stabilization system such as any of the above-mentioned technical solutions, and therefore the wafer illumination beam stabilization method has all the beneficial effects of the wafer illumination beam stabilization system of the above-mentioned technical solutions.

[0207] Example:

[0208] The wafer defect detection focus working process is as follows:

[0209] (1) Record the initial position of each light spot

[0210] Record the initial position of the second light spot on the object to be tested, that is, the initial position of the second light beam split from the light source beam focused on the object to be tested is X0, Y0, Z0, and the initial angle of the corresponding fast mirror lens is θ x0 ,θ Y0 , the initial position is ω x0 ,ω Y0 (This effect can be ignored by system simulation analysis, which will be analyzed later). Record the initial position of the first light spot in the light source monitoring component, that is, the initial position U of the light spot of the first light beam in the light source monitoring component. X0 , U Y0 , record the initial angle of the surface of the test piece as (This effect can be ignored by system simulation analysis, which will be analyzed later). The initial position of the third light spot in the reflection monitoring component is recorded as T X0 , T Y0 .

[0211] (2) Collect the position of each light spot before adjustment

[0212] At a certain moment, when the light source beam in the stabilization system changes or the DUT is replaced, causing the second light spot formed by the second light beam converging on the surface of the DUT to shift, the reflection monitoring component collects the second light spot on the DUT before adjustment as X1, Y1, and Z1, and the corresponding fast mirror lens before adjustment is θ x1 ,θ Y1, the light source monitoring component collects the first light spot before adjusting the position U X1 , U Y1 , the reflection monitoring component collects the third light spot before adjusting the position T X1 , T Y1 .

[0213] Calculate the difference between the position of each light spot before adjustment and the corresponding initial position. If the position of the light spot before adjustment is within the tolerance of the corresponding initial position, adjust the lighting component and the workpiece moving component; if the position of the light spot before adjustment is beyond the tolerance of the corresponding initial position, calculate the deviation:

[0214] byU X1 , U Y1 The change in the incident angle of the first beam of the light source can be calculated: ΔU x =A x Δθ x =U x1 -U x0 , ΔU Y =A Y Δθ Y =U Y1 -U Y0 ,Right now

[0215] By T X1 , T Y1 , Δθ x , Δθ Y The displacement of the second light spot on the Z axis can be calculated as: ΔT x =F x Δθ x +GΔZ=T x1 -T x0 , ΔT Y =F Y Δθ Y =T Y1 -T Y0 ,Right now (The angular offset of the first light beam in the Y direction is the same as the angular offset of the second light spot in the Y direction).

[0216] (3) Fast-reflecting mirror adjusts the light beam

[0217] The offset of the second light spot on the surface of the corresponding test piece is: ΔX = C x Δθ x +DΔZ,ΔY=C Y Δθ Y .

[0218] If the position of the second light spot remains unchanged, the actual adjustment amount of the fast-reflecting mirror lens angle can be obtained as Δθ Yc =ΔθY After adjustment, the spot position in the light source monitoring component can be calculated as U xc =U x1 +A x Δθ xc , U Yc =U Y1 +A Y Δθ Yc , the spot position in the reflection monitoring component is T xc =T x1 +F x Δθ xc , T Yc =T Y1 +F Y Δθ Yc .

[0219] (4) Collect the adjusted positions of each light spot again

[0220] After adjustment, the light spot position in the light source monitoring component is U X2 , U Y2 , the light spot position in the reflection monitoring component is T X2 , T Y2 At this time, if the stabilization system limits the laser spot offset to no more than 2um in both the X and Y directions, then

[0221]

[0222]

[0223] In the stabilization system, through the design and simulation of the optical system, the angle unit is urad, the position unit is um, and the corresponding parameters are A x =-6.97072×10 -4 , A y =-6.976993×10 -4 、F x =-2.78618×10 -3 、F y =-2.75276×10 -3 , G=34.5520, C x =-6.04338×10 -4 , C y =-1.56174×10 -4 , D=3.738.

[0224] That is U x2 -U x0 ≤2.3um

[0225] U Y2 -U Y0≤8.94um

[0226] T x2 -T x0 ≤9.22um

[0227] T Y2 -T Y0 ≤35.2um

[0228] If the deviation after calibration is greater than the adjustment threshold setting, the measured U X2 , U Y2 , T X2 , T Y2 Substitute U into step (2) X1 , U Y1 , T X1 , T Y1 Repeat the calibration adjustment procedure.

[0229] Since both the lighting components and the light source monitoring components in the system are stable systems, it can be known from the zemax simulation that the optical axis of the light source beam is translated in the X direction ω x1 =0.1mm, corresponding to the second light spot offset on the test piece is 0.197um; corresponding to the third light spot offset on the reflection monitoring component is 0.325um. The optical axis of the light source beam is translated in the Y direction ω Y1 =0.1mm, corresponding to the second light spot offset on the test piece is 0.048um; corresponding to the third light spot offset on the reflection monitoring component is 0.146um. Compared with the adjustment threshold set by the system, they are one order of magnitude smaller, and the impact is small and can be ignored.

[0230] Similarly, the wafer rotating table is usually leveled. After leveling, the edge height difference of the rotating table is about 10um after one rotation. When the rotating table carries a 12-inch wafer with a diameter of 304.8mm, the corresponding angle deviation of the test piece is Similarly, The corresponding third light spot on the reflection monitoring component has an offset of 0.106um in the X direction and 0.417um in the Y direction, which are both one order of magnitude smaller than the adjustment thresholds set by the system, and the impact is small and can be ignored.

[0231] It is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0232] The above are only preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application. The above are only preferred implementations of the present application. It should be pointed out that for ordinary technicians in this technical field, several improvements and variations can be made without departing from the technical principles of the present application, and these improvements and variations should also be regarded as the protection scope of the present application.

Claims

1. A wafer illumination beam stabilization system, the wafer illumination beam stabilization system is arranged on a platform, characterized in that: The wafer illuminating beam stabilization system comprises: An illumination component, wherein the illumination component refracts the light beam of the light source to form at least a first light beam and a second light beam, and the illumination component is adjustably disposed on the platform to adjust the splitting angle of the light beam of the light source; A workpiece moving assembly, the workpiece moving assembly is used to move a workpiece to be tested, the workpiece to be tested receives the second light beam and can reflect a third light beam; A reflection monitoring component, wherein the reflection monitoring component is used to monitor a light spot formed by the third light beam; A signal control component is used to control the movement of the workpiece moving component, the signal control component receives the detection signal of the reflection monitoring component, and the signal control component transmits a control signal to the workpiece moving component at least according to the detection signal of the reflection monitoring component.

2. A wafer illumination beam stabilization system according to claim 1, characterized in that: The lighting assembly includes a beam adjustment assembly, a prism assembly and a beam focusing assembly, wherein the beam adjustment assembly reflects the light source beam onto the prism assembly, the prism assembly splits the light into the first beam and the second beam, and the second beam enters the beam focusing assembly; The beam adjustment component is adjustably disposed on the platform to adjust the angles of the first beam and the second beam.

3. A wafer illumination beam stabilization system according to claim 2, characterized in that: The beam adjustment assembly comprises: Fast-reflection mirror mount; An adjustment system, the adjustment system is electrically connected to the signal control component, the adjustment system comprises a first adjustment mechanism, and the adjustment system is arranged on the quick-reflection mirror base; A quick-reflection mirror lens is arranged on the first adjustment mechanism.

4. The wafer illumination beam stabilization system according to claim 2, characterized in that: The optical system of the beam focusing assembly is an anti-telephoto system, and the beam focusing assembly comprises: Focusing lens barrel bracket; A focusing lens barrel, wherein the focusing lens barrel is arranged on the focusing lens barrel bracket; A plurality of focusing lenses are arranged in the focusing lens barrel.

5. The wafer illumination beam stabilization system according to claim 1, characterized in that: 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: Base; a second adjustment mechanism, the second adjustment mechanism being electrically connected to the signal control component and being disposed on the base; A rotating mechanism, the rotating mechanism is electrically connected to the signal control component, the rotating mechanism is arranged on the moving platform of the second adjustment mechanism, the rotating mechanism includes a rotating platform, and the test piece is arranged on the rotating platform.

6. The wafer illumination beam stabilization system according to claim 1, characterized in that: The reflection monitoring component includes a reflection monitoring mirror group component, a reflection monitoring turning mirror component and a reflection monitoring detector component. The reflection monitoring turning mirror component is arranged on the light output side of the reflection monitoring mirror group component, and the reflection monitoring detector component is arranged on the light output side of the reflection monitoring turning mirror component.

7. The wafer illumination beam stabilization system according to claim 6, characterized in that: The optical system of the light source monitoring mirror assembly is a telephoto focusing system, and the reflection monitoring mirror assembly includes: Reflection monitoring lens tube bracket; A reflective monitoring lens barrel, wherein the reflective monitoring lens barrel is arranged on the reflective monitoring lens barrel bracket; A reflection monitoring lens, wherein a plurality of the reflection monitoring lenses are arranged in the reflection monitoring lens barrel.

8. A wafer illumination beam stabilization system according to any one of claims 1 to 7, characterized in that: The wafer illuminating beam stabilization system further comprises: A light source monitoring component is used to receive the first light beam and monitor a light spot formed by the first light beam.

9. The wafer illumination beam stabilization system according to claim 8, characterized in that: The signal control component receives the detection signal of the light source monitoring component, and the signal control component transmits a control signal to the lighting component according to the detection signal of the light source monitoring component.

10. A wafer illuminating light beam stabilization method, characterized in that: The wafer is inspected using the wafer illumination beam stabilization system as claimed in any one of claims 1 to 9, comprising: The illumination component divides the light beam of the light source into the first light beam and the second light beam, focuses the second light beam onto the workpiece to be tested mounted on the workpiece moving component to reflect to form the third light beam, and reflects the third light beam into the reflection monitoring component to form the light spot; Acquire a first initial position of a light spot monitored by the reflection monitoring component; Collecting a first pre-adjustment position of the light spot monitored by the reflection monitoring component; Obtaining a first offset of the light spot monitored by the reflection monitoring component according to a first pre-adjustment position and a first initial position recorded by the reflection monitoring component; The workpiece moving component is adjusted according to a first offset of the light spot monitored by the reflection monitoring component.

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