Laser positioning device and wafer inspection system

Abstract

This invention provides a laser positioning device and wafer inspection system that improve positioning accuracy. [Solution] In the laser positioning device, stage 1 includes a moving mechanism 11 that drives a carrier 12 to move in a first direction X and a second direction Y, and a measuring mirror 13 attached to the carrier, wherein the first measuring surface 131 of the measuring mirror intersects the first direction, and the second measuring surface 132 intersects the second direction. The orthogonality test feedback assembly 2 is provided with first and second measuring heads 21 and 22, the first measuring head emits a first laser beam 5 toward the first measuring surface along the first direction, the second measuring head emits a second laser beam 6, and the optical path assembly 3 divides the second laser beam into a plurality of third laser beams 7 and emits them toward the second measuring surface along the second direction. The first laser beam and the plurality of third laser beams improve positioning accuracy and reduce the Abbe error of measurement.

Description

Technical Field

[0001] This application belongs to the field of semiconductor technology, and particularly relates to a laser positioning device and a wafer inspection system.

Background Art

[0002] With the development of semiconductor technology, the requirements for semiconductor devices are increasing. When performing inspections or other operations on a wafer, it is necessary to accurately position the stage on which the wafer is placed, thereby improving the measurement accuracy and defect detection rate in advanced manufacturing processes.

[0003] In related technologies, the stage on which the wafer is placed by the stage can be driven to translate the wafer, thereby satisfying the displacement requirements of wafer inspection. The stage uses a grating scale for positioning. However, when positioning the wafer with reference to the grating scale, there is an Abbe error in measurement because the distance between the grating scale and the wafer is large.

Summary of the Invention

[0004] Embodiments of this application provide a laser positioning device and a wafer inspection system that can improve positioning accuracy.

[0005] In a first embodiment, an embodiment of the present application provides a laser positioning device comprising a stage, an orthogonality test feedback assembly, and an optical path assembly, wherein the stage comprises a moving mechanism, a carrier, and a measuring mirror, the moving mechanism is used to drive the carrier to move in a first direction and a second direction, the measuring mirror is mounted on the carrier, the first measuring surface of the measuring mirror intersects the first direction, and the second measuring surface of the measuring mirror intersects the second direction, the orthogonality test feedback assembly is provided with a first measuring head and a second measuring head, the first measuring head emits a first laser beam toward the first measuring surface along the first direction, the second measuring head emits a second laser beam, and the optical path assembly is used to divide the second laser beam into a plurality of third laser beams and emit them toward the second measuring surface along the second direction.

[0006] Selectively, the optical path assembly includes a spectral assembly and a reflection assembly, wherein the spectral assembly is located in the optical path of the second laser beam and is used to split the second laser beam into a first reflected laser beam and one of the third laser beams, and the reflection assembly is located in the optical path of the first reflected laser beam and is used to reflect the first reflected laser beam into another of the third laser beams.

[0007] Selectively, the spectral assembly includes a first spectral mirror, with the second laser beam and the first reflected laser beam on one side of the first spectral mirror and the third laser beam on the other side of the first spectral mirror; and the reflection assembly includes a reflection mirror, with the first reflected laser beam and the third laser beam on one side of the reflection mirror.

[0008] Selectively, the spectroscopic assembly further includes a second spectroscopic mirror, which is positioned between the first spectroscopic mirror and the reflection mirror, and transmits the first reflection beam to form a third laser beam.

[0009] Selectively, the angle between the first reflected laser beam and the second laser beam is 90°, and the angle between the first reflected laser beam and the third laser beam is 90°.

[0010] Selectively, the transmission-reflectance ratio of the first spectral mirror is 1:2, and the transmission-reflectance ratio of the second spectral mirror is 1:1.

[0011] Selectively, the carrier includes a mounting plate and a suction cup, wherein the mounting plate is attached to the moving mechanism, the suction cup is attached to the mounting plate, the measuring mirror is attached to the mounting plate, the height of the measuring mirror is lower than the height of the suction cup, the first measuring surface of the measuring mirror is perpendicular to the first direction, the second measuring surface of the measuring mirror is perpendicular to the second direction, and the first measuring surface is perpendicular to the second measuring surface.

[0012] Selectively, the moving mechanism includes a first moving mechanism and a second moving mechanism, the first moving mechanism is provided with a first grid scale, the first moving mechanism is used to move in a first direction, the first grid scale is used to control the operation of the first moving mechanism, the second moving mechanism is mounted on the first moving mechanism, the second moving mechanism is provided with a second grid scale, the second moving mechanism is used to move in a second direction, and the second grid scale is used to control the operation of the second moving mechanism.

[0013] In a second embodiment, the present invention provides a wafer inspection system comprising a device body and a laser positioning device, wherein the device body is provided with a plurality of inspection heads, the plurality of inspection heads are located above the stage and are used to inspect wafers on the stage, and the inspection points of the plurality of inspection heads are each located at the intersection of the first laser beam path and the third laser beam path.

[0014] Selectively, the inspection head includes a first inspection head, a second inspection head, and a third inspection head, wherein the first inspection head is an electro-optical inspection head, the second inspection head is a geometrical optical inspection head, and the third inspection head is a deep ultraviolet geometrical optical inspection head.

[0015] Embodiments of the present invention provide a laser positioning device and a wafer inspection system, the laser positioning device comprising a stage, an orthogonal test feedback assembly, and an optical path assembly. The stage can drive the wafer to move in a first and second direction, and by mounting a measuring mirror on the stage, a positioning reference can be provided to the orthogonal test feedback assembly. A first measuring head of the orthogonal test feedback assembly emits a first laser beam to a first measuring surface, and a second laser beam emitted by a second measuring head is divided into a plurality of third laser beams by the optical path assembly and emitted to the second measuring surface, thereby enabling precise positioning at the intersection of the optical paths of the first laser beam and the plurality of third laser beams, improving positioning accuracy and reducing Abbe error in measurement. [Brief explanation of the drawing]

[0016] To more clearly explain the technical concept of the embodiments of this application, the drawings necessary for use in the embodiments of this application are briefly described below. Those skilled in the art can obtain other drawings based on these without requiring any creative effort. [Figure 1] This is a schematic diagram of the structure of a laser positioning device according to some embodiments of the present application, viewed from one perspective. [Figure 2] This is a schematic diagram of the structure of a laser positioning device according to some embodiments of the present application, viewed from a different angle. [Figure 3] This is a schematic diagram of an optical path assembly according to several embodiments of the present application. [Figure 4] This is a schematic diagram of an optical path assembly according to several other embodiments of the present application. [Modes for carrying out the invention]

[0017] The features and exemplary embodiments of each aspect of the present application will be described in detail below, and the present application will be described in further detail below with reference to the drawings and specific embodiments in order to provide a clearer understanding of its purpose, technical proposal and advantages. The specific embodiments described herein are for illustrative purposes only and do not limit the present application. A person skilled in the art may implement the present application without needing some of these specific details. The following description of embodiments is merely to provide examples of the present application for a better understanding.

[0018] In this specification, relational terms such as "first" and "second" are used solely to distinguish one entity or operation from another, and do not necessarily require or imply that such an actual relationship or order exists between these entities or operations. Furthermore, the terms "includes," "equips," "has," or any other variation thereof mean that a process, method, article, or apparatus containing a set of elements includes not only those elements but also other elements not explicitly listed, or further elements specific to such a process, method, article, or apparatus. Unless otherwise specified, elements limited by the phrases "includes," "equips," or "has" do not preclude other identical elements from being present in a process, method, article, or apparatus containing such elements.

[0019] With the advancement of semiconductor technology and process technology, the line width of integrated circuits is becoming increasingly smaller, and the demands on circuit production process technology are also rising. At the same time, semiconductor foundry companies are imposing higher demands on semiconductor devices in order to reduce costs, improve production efficiency, and increase cleanroom utilization.

[0020] When optical inspection, exposure, or other equipment performs inspection or other operations on a wafer, it is necessary to achieve full-range positioning and measurement on the stage on which the wafer is placed, thereby improving measurement accuracy and defect detection rates in advanced manufacturing processes. When inspecting a wafer, inspection equipment typically integrates multiple inspection modes and inspects the same wafer on the same stage in multiple modes. Each inspection mode corresponds to one inspection head, and each inspection head has a certain volume. In the assembly design, adjacent inspection heads are placed at a certain distance apart to avoid mutual interference when mounting multiple inspection heads. Also, since the support surface of the stage has a certain size (for example, a 300mm x 300mm square support surface), the inspection points of multiple inspection heads can be distributed to different positions, forming multiple inspection points.

[0021] In related technologies, the stage includes an X-axis movement mechanism and a Y-axis movement mechanism, and positioning is achieved by displacement control of the X-axis and Y-axis movement mechanisms using a grid scale. However, when positioning multiple inspection points on a wafer, an Abbe error in measurement exists due to the large distance between the grid scale and the wafer. Therefore, embodiments of the present application provide a laser positioning device and a wafer inspection system.

[0022] Referring to Figures 1 to 4, Figure 1 is a schematic diagram of the structure of a laser positioning device according to some embodiments of the present application from one viewing angle, Figure 2 is a schematic diagram of the structure of a laser positioning device according to some embodiments of the present application from another viewing angle, Figure 3 is a schematic diagram of the structure of an optical path assembly according to some embodiments of the present application, and Figure 4 is a schematic diagram of the structure of an optical path assembly according to some other embodiments of the present application.

[0023] In the first aspect, as shown in FIGS. 1 and 2, the embodiment of the present application provides a laser positioning device, which includes a stage 1, an orthogonality test feedback assembly 2, and an optical path assembly 3. The stage 1 includes a moving mechanism 11, a carrier 12, and a measurement mirror 13. The carrier 12 is attached to the moving mechanism 11, and the moving mechanism 11 is used to move the carrier 12 in the first direction X and the second direction Y. The measurement mirror 13 is installed on the carrier 12, the first measurement surface 131 of the measurement mirror 13 intersects the first direction X, and the second measurement surface 132 of the measurement mirror 13 intersects the second direction Y. The orthogonality test feedback assembly 2 includes a first measurement head 21 and a second measurement head 22. The first measurement head 21 emits a first laser beam 5 along the first direction X toward the first measurement surface 131, and the second measurement head 22 emits a second laser beam 6. The optical path assembly 3 receives the second laser beam 6 emitted from the second measurement head 22, divides the second laser beam 6 into a plurality of third laser beams 7, and emits them along the second direction Y toward the second measurement surface 132.

[0024] The stage 1 realizes the movement in the first direction X and the second direction Y by the moving mechanism 11. When the first direction X intersects the second direction Y, for example, by setting the first direction X to be perpendicular to the second direction Y, the movement of the carrier 12 within the plane can be realized. The carrier 12 is attached on the moving mechanism 11, provides a carrier for the workpiece (for example, the wafer 4), and is used to play the role of placement. The measurement mirror 13 is attached to the carrier 12, receives the first laser beam 5 through the first measurement surface 131, receives the third laser beam 7 through the second measurement surface 132, and can provide a positioning reference for the first laser beam 5 and the third laser beam 7.

[0025] The orthogonality test feedback assembly 2 may include an orthogonality test feedback body 23, a first measuring head 21, and a second measuring head 22. Each orthogonality test feedback body 23 is connected to one first measuring head 21 and one second measuring head 22, and the first measuring head 21 and the second measuring head 22 can work together with the orthogonality test feedback body 23 to achieve distance measurement. Exemplarily, a first laser beam 5 emitted from the first measuring head 21 reaches a first measuring surface 131 and returns, and a second laser beam 6 emitted from the second measuring head 22 reaches a second measuring surface 132 and returns along its original path. The returning laser beams form an interference pattern on the orthogonality test feedback body 23. As the position of stage 1 changes, the optical path difference between the first laser beam 5 and the second laser beam 6 changes, and the interference pattern changes. The orthogonality test feedback body 23 can calculate the displacement of stage 1 through monitoring and analysis. The orthogonality test feedback assembly 2 can be used with a laser interferometer.

[0026] Each orthogonality test feedback assembly 2 has only one first measurement head 21 and one second measurement head 22. By emitting lasers from the first measurement head 21 and the second measurement head 22, the planar positioning of one inspection point can be directly realized, but the positioning requirements of multiple inspection points cannot be satisfied. In contrast, the first measurement head 21 can realize the accurate positioning of multiple inspection points in the first direction X by emitting the first laser beam 5 toward the first measurement surface 131 along the first direction X. The second laser beam 6 emitted from the second measurement head 22 is emitted toward the optical path assembly 3, and the optical path assembly 3 can divide the second laser beam 6 into multiple third laser beams 7, and by emitting the multiple third laser beams 7 toward the second measurement surface 132 along the second direction Y, the accurate positioning of multiple inspection points in the second direction Y can be realized. One first laser beam 5 and multiple third laser beams 7 can form multiple intersections in the optical path, thereby realizing the global positioning for multiple inspection points. Since the first laser beam 5 and the third laser beam 7 are located on the straight line in the positioning direction of the inspection point, the Abbe error can be reduced.

[0027] The optical path assembly 3 can receive the second laser beam 6 and divide the second laser beam 6 into multiple third laser beams 7 by splitting the second laser beam 6, and multiple third laser beams 7 and one first laser beam 5 can form multiple intersections on the optical path, and the number of intersections is consistent with the number of the third laser beams 7.

[0028] In the technical proposal of the above embodiment, the laser beam positioning device includes a stage 1, an orthogonality test feedback assembly 2, and an optical path assembly 3. Stage 1 can serve as a mounting and positioning reference. The orthogonality test feedback assembly 2 and the optical path assembly 3 can form one first laser beam 5 and multiple third laser beams 7. The first laser beam 5 and the multiple third laser beams 7 form multiple intersections on the optical path, each intersection corresponding to one inspection point, thereby enabling the positioning of multiple inspection points. Since both the first laser beam 5 and the third laser beams 7 are located on a straight line in the positioning direction of the inspection points, Abbe error during measurement is reduced, improving positioning accuracy and providing precise positioning of multiple inspection points.

[0029] In some embodiments, as shown in Figure 3, the optical path assembly 3 includes a spectral assembly 31 and a reflection assembly 32. The spectral assembly 31 is located on the optical path of the second laser beam 6 and is used to spectrally separate the second laser beam 6 into a first reflected laser beam 8 and a third laser beam 7. The reflection assembly 32 is located on the optical path of the first reflected laser beam 8 and is used to reflect the first reflected laser beam 8 into another third laser beam 7.

[0030] The spectral assembly 31 is located on the optical path where the second laser beam 6 is located, and the reflection assembly 32 is located on the optical path where the first reflected laser beam, formed by specular reflection of the second laser beam 6 by the spectral assembly 31, is located. When the second laser beam 6 is irradiated onto the spectral assembly 31, the spectral assembly 31 splits the second laser beam 6 into two beams, one of which is the first reflected laser beam 8 and the other is the third laser beam 7. The first reflected laser beam 8 is irradiated onto the reflection assembly 32, and the reflection assembly 32 can change the transmission direction of the first reflected laser beam 8 to change it into the third laser beam 7.

[0031] The spectral assembly 31 and the reflection assembly 32 work together to split one second laser beam 6 into two third laser beams 7. For example, the spectral assembly 31 may be a spectral mirror, and the reflection assembly 32 may be a reflection mirror 321. The spectral mirror enables a change in the number of laser beams and a change in their propagation path, while the reflection mirror 321 enables a change in the propagation path of the laser beams.

[0032] In the above embodiment, the spectral assembly 31 and the reflection assembly 32 can split one second laser beam 6 into two third laser beams 7, the two third laser beams 7 irradiating the second measuring surface 132 along the second direction Y, and the two third laser beams 7 and the one first laser beam 5 can form two intersection points in the optical path, thereby providing precise positioning of two inspection points.

[0033] In some embodiments, as shown in Figure 3, the spectral assembly 31 includes a first spectral mirror 311, with one side of the first spectral mirror 311 being the second laser beam 6 and the first reflected laser beam 8, and the other side being the third laser beam 7. The reflection assembly 32 includes a reflection mirror 321, with one side of the reflection mirror 321 being the first reflected laser beam 8 and the third laser beam 7.

[0034] The second laser beam 6 is irradiated onto the first spectral mirror 311, which transmits and reflects the second laser beam 6. After transmission, it forms a third laser beam 7, and after reflection, it forms a first reflected laser beam 8. The first reflected laser beam 8 is emitted onto the reflection mirror 321, which specularly reflects the first reflected laser beam, changing its propagation path and forming another third laser beam 7.

[0035] In the above embodiment, the second laser beam 6 and the first reflected laser beam 8 are positioned on the same side of the first spectral mirror 311, making it easier to obtain an optical path through specular reflection and simplifying the arrangement of the position and angle of the reflecting mirror 321.

[0036] In some embodiments, as shown in Figure 4, the spectral assembly 31 further includes a second spectral mirror 312, which is located between the first spectral mirror 311 and the reflection mirror 321 and is used to transmit the first reflected beam to form a third laser beam 7.

[0037] The second spectral mirror 312 is positioned on the optical path of the first reflected laser beam 8, directing the first reflected laser beam 8 toward the second spectral mirror 312. The second spectral mirror 312 transmits a portion of the first reflected beam to the reflection mirror 321, reflecting the rest of the first beam and changing its propagation path, thereby converting it into the third laser beam 7.

[0038] The third laser beam 7 formed by the first spectral mirror 311 is formed by transmission through the first spectral mirror 311. The third laser beam 7 formed by the second spectral mirror 312 is formed by reflection through the second spectral mirror 312. The third laser beam 7 formed by the reflection mirror 321 is formed by reflection through the reflection mirror 321.

[0039] In the above embodiment, the optical path assembly 3 includes a first spectral mirror 311, a second spectral mirror 312, and a reflection mirror 321. After the second laser beam 6 is emitted from the optical path assembly 3, three third laser beams 7 can be formed. The three third laser beams 7 and the one first laser beam 5 can form three intersection points in the optical path, thereby allowing for the precise positioning of three inspection points.

[0040] In some embodiments, as shown in Figure 4, the angle between the first reflected laser beam 8 and the second laser beam 6 is 90°, and the angle between the first reflected laser beam 8 and the third laser beam 7 is 90°.

[0041] The first reflected laser beam 8 and the second laser beam 6 are positioned vertically, and the first spectral mirror 311 is a 90° spectral mirror that can split the incident light at a 90° angle, that is, it splits the second laser beam 6 into one third laser beam 7 and one first reflected laser beam 8 at a 90° angle. The first reflected laser beam 8 and the third laser beam 7 are positioned vertically, and the second spectral mirror 312 is a 90° spectral mirror that can split the incident light at a 90° angle, that is, it splits the first reflected laser beam 8 into one third laser beam 7.

[0042] In the above embodiment, the first reflected laser beam 8 is perpendicular to the second laser beam 6 and the third laser beam 7, respectively, and the second laser beam 6 and the third laser beam 7 are perpendicular to each other. This facilitates the control of the laser beam's optical path and further simplifies the arrangement of the first spectral mirror 311, the second spectral mirror 312, and the third spectral mirror.

[0043] In some embodiments, as shown in Figure 4, the transmission-reflectance ratio of the first spectral mirror 311 is 1:2, and the transmission-reflectance ratio of the second spectral mirror 312 is 1:1.

[0044] When facing the incident beam, the first spectral mirror 311 transmits 1 / 3 of the light intensity of the incident beam and reflects 2 / 3, while the second spectral mirror 312 transmits 1 / 2 of the light intensity of the incident beam and reflects 1 / 2. When the second laser beam 6 is incident on the first spectral mirror 311, it passes through the first spectral mirror 311 to form a third laser beam 7 of the first beam, and is reflected to form a first reflected laser beam 8. The light intensity of this third laser beam 7 becomes 1 / 3 of the light intensity of the second laser beam 6, and the light intensity of the first reflected laser beam 8 becomes 2 / 3 of the light intensity of the second laser beam 6. The first reflected laser beam 8 is irradiated onto the second spectral mirror 312, reflected by the second spectral mirror 312 to form the third laser beam 7 of the second beam. The light intensity of the third laser beam 7 is half that of the first reflected laser beam 8. The remaining half of the light intensity of the first reflected laser beam 8 passes through the second spectral mirror 312 and is then specularly reflected by the reflection mirror 321 to form the third laser beam 7 of the third beam.

[0045] In the above embodiment, the transmission-reflectance ratio of the first spectral mirror 311 is 1:2, and the transmission-reflectance ratio of the second spectral mirror 312 is 1:1. The light intensity of the three third laser beams 7 formed by the second laser beam 6 passing through the first spectral mirror 311, the second spectral mirror 312, and the reflection mirror 321 is equal, which improves positioning accuracy.

[0046] In some embodiments, as shown in Figures 1 and 2, the carrier 12 includes a mounting plate and a suction cup. The mounting plate is attached to the moving mechanism 11, and the suction cup is attached to the mounting plate. The measuring mirror 13 is similarly attached to the mounting plate. The height of the measuring mirror 13 is lower than the height of the suction cup. The first measuring surface 131 of the measuring mirror 13 is perpendicular to the first direction X, the second measuring surface 132 of the measuring mirror 13 is perpendicular to the second direction Y, and the first measuring surface 131 is perpendicular to the second measuring surface 132.

[0047] The mounting plate is attached to the moving mechanism 11 and provides mounting positions for the suction cup and the measuring mirror 13. The suction cup is attached to the mounting plate and can attract and fix the wafer 4 to the suction cup. The measuring mirror 13 is attached to the mounting plate and may be positioned at a distance from the suction cup or attached to the suction cup. When the suction cup is attached to the mounting plate, the distance between the mounting surface of the suction cup and the mounting plate is H1, and when the measuring mirror 13 is attached to the mounting plate, the distance between the upper surface on which the mirror is attached and the mounting plate is H2, where H1 > H2.

[0048] The measuring mirror 13 may be a single-piece structure or a segmented structure. For example, if the measuring mirror 13 is a single-piece structure, it may be divided into two parts perpendicular to each other, with a first measuring surface 131 located in the first part and a second measuring surface 132 located in the second part, one end of the first part connected to one end of the second part, and the first part perpendicular to the second part. If the measuring mirror 13 is a segmented structure, it may include a first measuring mirror and a second measuring mirror, with the first measuring surface 131 located in the first measuring mirror and the second measuring surface 132 located in the second measuring mirror, and the first measuring mirror perpendicular to the second measuring mirror.

[0049] In the above embodiment, the first measuring surface 131 of the measuring mirror 13 is perpendicular to the first direction X, and is positioned perpendicular to the first laser beam 5. The second measuring surface 132 of the measuring mirror 13 is perpendicular to the second direction Y, and is positioned perpendicular to the third laser beam 7, thereby improving positioning accuracy. Because the height of the measuring mirror 13 is lower than the height of the suction cup, contact with the wafer 4 can be avoided, and the wafer 4 will not be damaged.

[0050] In some embodiments, as shown in Figures 1 and 2, the moving mechanism 11 includes a first moving mechanism 112 and a second moving mechanism 111. The first moving mechanism 112 is provided with a first grid scale 1121, which is used to move in a first direction X, and the first grid scale 1121 is used to provide motion control to the first moving mechanism 112. The second moving mechanism 111 is attached to the first moving mechanism 112, and the second moving mechanism 111 is provided with a second grid scale 1111, which is used to move in a second direction Y, and the second grid scale 1111 is used to provide motion control to the second moving mechanism 111.

[0051] The first moving mechanism 112 moves in the first direction X, and the second moving mechanism 111 moves in the second direction Y. The first direction X and the second direction Y are perpendicular to each other, which enables the moving mechanisms 11 to move in a plane. The first grid scale 1121 can be connected to a higher-level device and controls the movement distance of the first moving mechanism 112. Similarly, the second grid scale 1111 can also be connected to a higher-level device and controls the movement distance of the second moving mechanism 111.

[0052] The first laser beam 5 is perpendicular to the first measuring surface 131, the third laser beam 7 is perpendicular to the second measuring surface 132, and the first measuring surface 131 is perpendicular to the second measuring surface 132.

[0053] In the above embodiment, the moving mechanism 11 can independently control translation in the first direction X and the second direction Y by providing a first moving mechanism 112 and a second moving mechanism 111, and the displacement of the suction cup can be controlled by the first grid scale 1121 and the second grid scale 1111 to improve the displacement accuracy of the suction cup.

[0054] In a second embodiment, as shown in Figure 2, an embodiment of the present application provides a wafer inspection system, which includes a device body 9 and a laser positioning device provided in the above-mentioned technical proposal. The device body 9 is provided with a plurality of inspection heads, which are located above a stage 1 and used to inspect wafers 4 on the stage 1. The inspection points of the plurality of inspection heads are each located at the intersection of a first laser beam path 5 and a third laser beam path 7.

[0055] The main body of the device 9 is a component of the main operational inspection function of the wafer 4 inspection system and also provides a mounting base for the laser positioning device. The inspection head acts as a port for the main body of the device 9 to inspect the wafer 4, and when inspecting, the inspection point coincides with the intersection of the optical path of the first laser beam 5 and the optical path of the third laser beam 7.

[0056] In the above embodiment, by setting the intersection point of the optical path of the first laser beam 5 and the optical path of the third laser beam 7, the laser positioning device can provide accurate positioning of multiple inspection points and reduce the Abbe error present during the inspection of the wafer 4.

[0057] In some embodiments, as shown in Figure 2, the inspection head includes a first inspection head 91, a second inspection head 92, and a third inspection head 93, where the first inspection head 91 is an electro-optical inspection head, the second inspection head 92 is a geometrical optical inspection head, and the third inspection head 93 is a deep ultraviolet geometrical optical inspection head.

[0058] The multiple inspection heads in the main body 9 are not located in a single location in space, but rather there is a distance difference between the centers of adjacent inspection heads, and the multiple inspection points of the multiple inspection heads are located on a straight line, and this straight line coincides with the optical path of the first laser beam 5. The first laser beam 5 can provide positioning in the first direction X to the multiple inspection points. Each third laser beam 7 corresponds to one inspection point and further provides positioning in the second direction Y to multiple inspection points.

[0059] The electro-optical inspection head, in cooperation with the main unit 9 of the apparatus, can perform characteristic dimension measurement to inspect the dimensions of the photoresist pattern on the wafer 4, perform defect inspection to inspect minute defects on the surface of the wafer 4, and further, is equipped with an energy scattering spectrometer to perform component analysis to analyze the elemental composition of the surface of the wafer 4.

[0060] The geometric optics inspection head, in cooperation with the main unit 9 of the apparatus, can perform visual and structural inspections to observe the external morphology of the wafer 4 and inspect for defects such as scratches, cracks, and contamination on the surface of the wafer 4. It can also analyze the deteriorated areas to observe the surface morphology of the deteriorated areas and determine the cause of deterioration, and perform metal analysis to analyze parameters such as the size, shape, and distribution of the crystal grains of the wafer 4.

[0061] The deep ultraviolet geometric optics inspection head, in cooperation with the main unit 9 of the device, can focus, transmit, and control light rays using deep ultraviolet light as a light source to inspect the size, surface roughness, flatness, thickness, and shape of the inspection wafer 4.

[0062] In the above embodiment of the proposed technology, the apparatus body 9 is equipped with an electro-optical inspection head, a geometrical optics inspection head, and a deep ultraviolet geometrical optics inspection head, enabling various types of inspections to be performed on the wafer 4. The inspection points formed when the electro-optical inspection head, geometrical optics inspection head, and deep ultraviolet geometrical optics inspection head inspect the wafer 4 are positioned in a one-to-one correspondence with the first laser beam 5 and a plurality of third laser beams 7, thereby improving the positioning accuracy during inspection.

[0063] In some embodiments, as shown in Figures 1, 2, and 4, the wafer inspection system includes a device body 9 and a laser positioning device, the device body 9 is provided with a first inspection head 91, a second inspection head 92, and a third inspection head 93, the first inspection head 91 being an electro-optical inspection head, the second inspection head 92 being a geometrical optical inspection head, and the third inspection head 93 being a deep ultraviolet geometrical optical inspection head, and the inspection modes of the head wafer inspection system include SEM electro-optical mode, OM geometrical optical mode, and DUV deep ultraviolet geometrical optical mode. The center-to-center distance deviation between the first inspection head 91 and the second inspection head 92 is the first center-to-center distance L1, and the center-to-center distance deviation between the first inspection head 91 and the third inspection head 93 is the second center-to-center distance L2. The laser positioning device is mounted on the device body 9 and includes a stage 1, an orthogonality test feedback assembly 2, and an optical path assembly 3, the stage 1 including a moving mechanism 11, a carrier 12, and a measuring mirror 13. The moving mechanism 11 includes a first moving mechanism 112 that moves in a first direction X, and the first moving mechanism 112 is provided with a first grid scale 1121. It also includes a second moving mechanism 111 that moves in a second direction Y, and the second moving mechanism 111 is provided with a second grid scale 1111. The second moving mechanism 111 is attached to the first moving mechanism 112, and the second direction Y is perpendicular to the first direction X. The mounting plate of the carrier 12 is attached to the second moving mechanism 111, the suction cup is attached to the mounting plate, and the measuring mirror 13 is attached to the mounting plate, with the upper surface of the measuring mirror 13 being lower than the mounting surface of the suction cup. The first measuring surface 131 and the second measuring surface 132 of the measuring mirror 13 are set perpendicular to each other, the first measuring surface 131 is perpendicular to the first direction X, and the second measuring surface 132 is perpendicular to the second direction Y. The length of the first measuring surface 131 in the second direction Y is 300 mm, and the length of the second measuring surface 132 in the first direction X is 300 mm, providing a positioning reference for a wafer 4 with a diameter of 300 mm. The optical path assembly 3 includes a first spectral mirror 311, a second spectral mirror 312, and a reflection mirror 321.

[0064] The first laser beam 5 emitted from the first measuring head 21 is irradiated perpendicularly to the first measuring surface 131 along the first direction X, providing positioning in the first direction X with respect to the inspection points on the wafer 4 of the first inspection head 91, second inspection head 92, and third inspection head 93. The second laser beam 6 emitted from the second measuring head 22 is irradiated toward the first spectral mirror 311, and passes through the first spectral mirror 311 to form a third laser beam 7 of the first beam. This third laser beam 7 is irradiated perpendicularly to the second measuring surface 132 along the second direction Y, providing positioning in the second direction Y with respect to the inspection points on the wafer 4 of the first inspection head 91. It is reflected by the second spectral mirror 312 to form a third laser beam 7 of the second beam, and this third laser beam 7 is irradiated perpendicularly to the second measuring surface 132 along the second direction Y, providing positioning in the second direction Y with respect to the inspection points on the wafer 4 of the second inspection head 92. The third laser beam 7 is reflected by the reflection mirror 321 and irradiated perpendicularly to the second measuring surface 132 along the second direction Y, providing positioning in the second direction Y with respect to the inspection point on the wafer 4 of the third inspection head 93.

[0065] When positioning the first inspection head 91, the second inspection head 92, and the third inspection head 93, the first laser beam 5 is positioned on the positioning line in the first direction X of the first inspection head 91, the second inspection head 92, and the third inspection head 93, the laser beam of the first beam is positioned on the positioning line in the second direction Y of the first inspection head 91, the laser beam of the second beam is positioned on the positioning line in the second direction Y of the second inspection head 92, and the laser beam of the third beam is positioned on the positioning line in the second direction Y of the third inspection head 93. This reduces Abbe error during positioning and improves positioning accuracy. Performing the positioning operation by combining one set of orthogonality test feedback assemblies 2 and one set of optical path assemblies 3 is simple, has low material costs, high positioning accuracy, and stable and reliable positioning accuracy.

[0066] The above description is a specific embodiment of the present application, and for the sake of convenience and brevity of explanation, as will be obvious to those skilled in the art, the specific operating processes of the systems, modules, and units described above should be referred to and omitted here. The scope of protection of this application is not limited thereto, and it should be understood that various equivalent modifications or substitutions that a person skilled in the art can easily conceive of within the scope of the art disclosed herein should be included within the scope of protection. [Explanation of symbols]

[0067] 1st Stage 11 Moving mechanism 111 Second movement mechanism 1111 Second lattice scale 112 1st movement mechanism 1121 First Grid Scale 12 carriers 13 Measuring mirror 131 First measuring surface 132 Second measuring surface, 2. Orthogonality Test Feedback Assembly 21 First measuring head 22 Second measuring head 23 Orthogonality Test Feedback Main Unit 3. Optical path assembly 31 Spectroscopic Assembly 311 First Spectroscopic Mirror 312 Second Spectroscopic Mirror 32 Reflective Assembly 321 Reflective Mirror 4 wafers 5. First laser beam 6. Second laser beam 7. Third laser beam 8. First reflected laser beam 9. Main unit of the device 91 First inspection head 92 Second inspection head 93 Third inspection head X 1st direction Y Second direction L1 1st center distance L2 Intercenter Distance

Claims

1. A laser positioning device, It includes a stage, an orthogonality test feedback assembly, and an optical path assembly, The stage includes a moving mechanism, a carrier, and a measuring mirror, the moving mechanism is used to drive the carrier to move in a first direction and a second direction, the measuring mirror is mounted on the carrier, the first measuring surface of the measuring mirror intersects the first direction, and the second measuring surface of the measuring mirror intersects the second direction, The orthogonality test feedback assembly is provided with a first measuring head and a second measuring head, the first measuring head emits a first laser beam toward the first measuring surface along the first direction, and the second measuring head emits a second laser beam. The optical path assembly is used to divide the second laser beam into a plurality of third laser beams and emit them along the second direction onto the second measuring surface. A laser positioning device characterized by the following features.

2. The optical path assembly includes a spectral assembly and a reflection assembly, The spectral assembly is located in the optical path of the second laser beam and is used to split the second laser beam into a first reflected laser beam and a third laser beam. The reflection assembly is located on the optical path of the first reflected laser beam and is used to reflect the first reflected laser beam to another third laser beam. The laser positioning device according to feature 1.

3. The spectroscopic assembly includes a first spectroscopic mirror, wherein the second laser beam and the first reflected laser beam are on one side of the first spectroscopic mirror, and the third laser beam is on the other side of the first spectroscopic mirror. The reflection assembly includes a reflection mirror, one side of which is the first reflection laser beam and the third laser beam. The laser positioning device according to feature 2.

4. The spectroscopic assembly further includes a second spectroscopic mirror, The second spectral mirror is located between the first spectral mirror and the reflection mirror and is used to transmit the first reflected laser beam to form a third laser beam. The laser positioning device according to feature 3.

5. The angle between the first reflected laser beam and the second laser beam is 90°. The angle between the first reflected laser beam and the third laser beam is 90°. The laser positioning device according to feature 3.

6. The transmission-reflectance ratio of the first spectral mirror is 1:2, and the transmission-reflectance ratio of the second spectral mirror is 1:

1. The laser positioning device according to feature 4.

7. The carrier includes a mounting plate and a suction cup. The mounting plate is attached to the moving mechanism, and the suction cup is attached to the mounting plate. The measuring mirror is attached to the mounting plate, the height of the measuring mirror is lower than the height of the suction cup, the first measuring surface of the measuring mirror is perpendicular to the first direction, the second measuring surface of the measuring mirror is perpendicular to the second direction, and the first measuring surface is perpendicular to the second measuring surface. The laser positioning device according to feature 1.

8. The aforementioned moving mechanism includes a first moving mechanism and a second moving mechanism, The first moving mechanism is provided with a first grid scale, the first moving mechanism is used to move in a first direction, and the first grid scale is used to control the operation of the first moving mechanism. The second moving mechanism is mounted on the first moving mechanism, the second moving mechanism is provided with a second grid scale, the second moving mechanism is used to move in the second direction, and the second grid scale is used to control the operation of the second moving mechanism. The laser positioning device according to feature 1.

9. A wafer inspection system, The apparatus comprises a main body and a laser positioning device according to any one of claims 1 to 8, The apparatus body is provided with a plurality of inspection heads, which are located above the stage and used to inspect wafers on the stage, and the inspection points of the plurality of inspection heads are located at the intersection of the optical path of the first laser beam and the optical path of the third laser beam, A wafer inspection system characterized by the following features.

10. The inspection head includes a first inspection head, a second inspection head, and a third inspection head. The first inspection head is an electro-optical inspection head, the second inspection head is a geometrical optical inspection head, and the third inspection head is a deep ultraviolet geometrical optical inspection head. The wafer inspection system according to feature 9.

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