Optical device and laser beam shape adjustment method

Abstract

The invention belongs to the technical field of optical instruments, and particularly relates to an optical device and a laser beam shape adjusting method.The optical device comprises a first cylindrical mirror set, a second cylindrical mirror set, a collimating mirror and a moving assembly; when the first cylindrical mirror in the first cylindrical mirror set moves relative to the second cylindrical mirror or the second cylindrical mirror moves relative to the first cylindrical mirror, the divergence angle of the laser beam after light condensation on the vertical plane is adjusted. When the third cylindrical mirror in the cylindrical mirror group II moves relative to the fourth cylindrical mirror or the fourth cylindrical mirror moves relative to the third cylindrical mirror, the divergence angle of the laser beam after condensation on the horizontal plane is adjusted; the divergence angles of the laser beams in the vertical direction and the horizontal direction can be independently changed, the diameters of the laser beams in the vertical direction and the horizontal direction can be changed, meanwhile, parallel light can be emitted, different requirements during wafer defect detection can be met, and smaller defect signals can be detected through the laser beams with the optimal uniformity.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical instruments, and particularly relates to a beam shaping device, and more particularly to an optical device and a method for adjusting the shape of a laser beam. Background Art

[0002] When detecting wafer defects, in order to quickly and accurately scan the wafer, it is necessary to adjust the shape of the laser beam. However, traditional optical devices can only adjust the divergence angles of the laser beam in the horizontal and vertical directions simultaneously through a single optical element, resulting in the adjustment in the two directions being coupled to each other and unable to be independently optimized, which affects the quality of the laser beam.

[0003] Therefore, there is an urgent need to develop a new optical device and a method for adjusting the shape of a laser beam to solve the technical problem that when the traditional optical device uses a single optical element to adjust the laser beam, the laser beam in the horizontal and vertical directions will be coupled to each other.

[0004] It should be noted that the above information disclosed in this background art section is only used to understand the background art of the concept of the present application. Therefore, the above description is not considered as information of the prior art. Summary of the Invention

[0005] The embodiments of the present disclosure at least provide an optical device and a method for adjusting the shape of a laser beam.

[0006] In a first aspect, the embodiments of the present disclosure provide an optical device, which includes: a first cylindrical lens group, a second cylindrical lens group, a collimating lens, and a moving component; wherein the first cylindrical lens group and the second cylindrical lens group are respectively located between the laser and the collimating lens, and the first cylindrical lens group, the second cylindrical lens group, and the collimating lens are respectively movably installed on the moving component; when the laser emits a laser beam, the laser beam is condensed on the vertical plane by the first cylindrical lens group, and the laser beam is condensed on the horizontal plane by the second cylindrical lens group until the laser beam is incident on the collimating lens, so that the collimating lens collimates and corrects the laser beam; when the first cylindrical lens in the first cylindrical lens group moves relative to the second cylindrical lens or the second cylindrical lens moves relative to the first cylindrical lens on the moving component, to adjust the divergence angle of the laser beam after being condensed on the vertical plane, the first cylindrical lens group moves relative to the collimating lens on the moving component until the focus point coincides with the focal length position of the collimating lens, and adjusts the angle size of the divergence angle to change the diameter of the laser beam emitted from the collimating lens on the vertical plane; when the third cylindrical lens in the second cylindrical lens group moves relative to the fourth cylindrical lens or the fourth cylindrical lens moves relative to the third cylindrical lens on the moving component, to adjust the divergence angle of the laser beam after being condensed on the horizontal plane, the second cylindrical lens group moves relative to the collimating lens on the moving component until the focus point coincides with the focal length position of the collimating lens, and adjusts the angle size of the divergence angle to change the diameter of the laser beam emitted from the collimating lens on the horizontal plane.

[0007] In an alternative embodiment, the first cylindrical lens group includes a first cylindrical lens and a second cylindrical lens. The first cylindrical lens and the second cylindrical lens are horizontally arranged and movably mounted on a moving component. The cylindrical surface of the first cylindrical lens faces the laser, the plane of the first cylindrical lens faces the plane of the second cylindrical lens, and the cylindrical surface of the second cylindrical lens faces the plane of the collimating lens. When the laser emits a laser beam towards the first cylindrical lens, the laser beam is condensed in the vertical plane through the first cylindrical lens and the second cylindrical lens until the laser beam hits the collimating lens, so that the collimating lens collimates and corrects the laser beam. When the first cylindrical lens moves relative to the second cylindrical lens or the second cylindrical lens moves relative to the first cylindrical lens on the moving component, the divergence angle of the laser beam after being condensed in the vertical plane is adjusted, and the first cylindrical lens and the second cylindrical lens as a whole move relative to the collimating lens on the moving component until the focal point coincides with the focal length position of the collimating lens, so that the laser beam emitted from the collimating lens is parallel to the laser beam emitted from the laser.

[0008] In an alternative embodiment, the second cylindrical lens group includes a third cylindrical lens and a fourth cylindrical lens. The third cylindrical lens and the fourth cylindrical lens are vertically arranged and movably mounted on a moving component. The cylindrical surface of the third cylindrical lens faces the laser, the plane of the third cylindrical lens faces the plane of the fourth cylindrical lens, and the cylindrical surface of the fourth cylindrical lens faces the plane of the collimating lens. When the laser emits a laser beam towards the first cylindrical lens, the laser beam is condensed horizontally through the first cylindrical lens and the second cylindrical lens until the laser beam hits the collimating lens, so that the collimating lens collimates and corrects the laser beam. When the third cylindrical lens moves relative to the fourth cylindrical lens or the fourth cylindrical lens moves relative to the third cylindrical lens on the moving component, the divergence angle of the laser beam after being condensed in the horizontal plane is adjusted, and when the third cylindrical lens and the fourth cylindrical lens as a whole move relative to the collimating lens on the moving component until the focal point coincides with the focal length position of the collimating lens, the laser beam emitted from the collimating lens is parallel to the laser beam emitted from the laser.

[0009] In an alternative embodiment, a spherical surface is provided on the collimating lens to collimate and correct the laser beam emitted from the collimating lens, and the laser beam emitted from the collimating lens is parallel to the laser beam emitted from the laser.

[0010] In an alternative embodiment, determine the position of the collimating lens on the moving component and the focal length of the collimating lens; determine the diameter of the laser beam emitted from the collimating lens in the vertical plane to obtain the divergence angle of the laser beam after being condensed in the vertical plane; determine the diameter of the laser beam emitted from the laser in the vertical plane to obtain the focal length of the first cylindrical lens group; configure the optical parameters and the position on the moving component of the first cylindrical lens and the second cylindrical lens according to the focal length of the first cylindrical lens group.

[0011] In an alternative embodiment, determine the position of the collimating mirror on the moving component and the focal length of the collimating mirror; determine the diameter of the laser beam emitted from the collimating mirror on the horizontal plane to obtain the divergence angle of the laser beam after focusing on the horizontal plane; determine the diameter of the laser beam emitted from the laser on the horizontal plane to obtain the focal length of the second cylindrical lens group; configure the optical parameters of the third cylindrical lens and the fourth cylindrical lens and their positions on the moving component based on the focal length of the second cylindrical lens group.

[0012] In an alternative embodiment, the moving component includes: a moving track; the first cylindrical lens group, the second cylindrical lens group, and the collimating mirror are respectively snap-mounted on the moving track.

[0013] In a second aspect, an embodiment of the present disclosure further provides a method for adjusting the shape of a laser beam as described above, which includes: when the laser emits a laser beam, the laser beam is focused on the vertical plane by the first cylindrical lens group, and the laser beam is focused on the horizontal plane by the second cylindrical lens group until the laser beam hits the collimating mirror, so that the collimating mirror collimates and corrects the laser beam; when the first cylindrical lens in the first cylindrical lens group moves relative to the second cylindrical lens or the second cylindrical lens moves relative to the first cylindrical lens on the moving component, to adjust the divergence angle of the laser beam after focusing on the vertical plane, the first cylindrical lens group moves relative to the collimating mirror on the moving component until the focal point coincides with the focal length position of the collimating mirror, and the angle size of the divergence angle is adjusted to change the diameter of the laser beam emitted from the collimating mirror on the vertical plane; when the third cylindrical lens in the second cylindrical lens group moves relative to the fourth cylindrical lens or the fourth cylindrical lens moves relative to the third cylindrical lens on the moving component, to adjust the divergence angle of the laser beam after focusing on the horizontal plane, the second cylindrical lens group moves relative to the collimating mirror on the moving component until the focal point coincides with the focal length position of the collimating mirror, and the angle size of the divergence angle is adjusted to change the diameter of the laser beam emitted from the collimating mirror on the horizontal plane.

[0014] In an alternative embodiment, determine the position of the collimating mirror on the moving component and the focal length of the collimating mirror; determine the diameter of the laser beam emitted from the collimating mirror on the vertical plane to obtain the divergence angle of the laser beam after focusing on the vertical plane; determine the diameter of the laser beam emitted from the laser on the vertical plane to obtain the focal length of the first cylindrical lens group; configure the optical parameters of the first cylindrical lens and the second cylindrical lens and their positions on the moving component based on the focal length of the first cylindrical lens group.

[0015] In an alternative embodiment, determine the position of the collimating mirror on the moving component and the focal length of the collimating mirror; determine the diameter of the laser beam emitted from the collimating mirror on the horizontal plane to obtain the divergence angle of the laser beam after focusing on the horizontal plane; determine the diameter of the laser beam emitted from the laser on the horizontal plane to obtain the focal length of the second cylindrical lens group; configure the optical parameters of the third cylindrical lens and the fourth cylindrical lens and their positions on the moving component based on the focal length of the second cylindrical lens group.

[0016] The beneficial effects of the present invention are as follows. By changing the positions of the first cylindrical mirror and the second cylindrical mirror in the first cylindrical mirror group and the positions of the third cylindrical mirror and the fourth cylindrical mirror in the second cylindrical mirror group, the divergence angles of the laser beam in the vertical and horizontal directions can be changed separately. And by adjusting the positions of the first cylindrical mirror group, the second cylindrical mirror group and the collimating mirror, the diameters of the laser beam in the vertical and horizontal directions can be changed, and at the same time, parallel light can be emitted, meeting different requirements when detecting wafer defects, and enabling the laser beam to detect smaller defect signals with optimal uniformity.

[0017] Other features and advantages of the present invention will be described in the following specification, and part of them will become obvious from the specification or be understood by implementing the present invention. The objectives and other advantages of the present invention are achieved and obtained by the structures specifically pointed out in the specification and the drawings.

[0018] To make the above objectives, features and advantages of the present invention more obvious and understandable, specific preferred embodiments are hereby given and described in detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0020] Figure 1 The structural diagram of an optical device provided by an embodiment of the present disclosure; Figure 2 The schematic diagram of adjusting the laser beam in the vertical direction provided by an embodiment of the present disclosure; Figure 3 The schematic diagram of adjusting the laser beam in the horizontal direction provided by an embodiment of the present disclosure; Figure 4 The schematic diagram of the change of the laser beam provided by an embodiment of the present disclosure.

[0021] In the figure: 1. The first cylindrical mirror group; 11. The first cylindrical mirror; 111. The first side; 112. The second side; 12. The second cylindrical mirror; 121. The third side; 122. The fourth side; 2. The second cylindrical mirror group; 21. The third cylindrical mirror; 211. The fifth side; 212. The sixth side; 22. The fourth cylindrical mirror; 221. The seventh side; 222. The eighth side; 3. The collimating mirror; 31. The ninth side; 32. The tenth side; 4. Moving component; 41. Moving track. Detailed implementation manner

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Apparently, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0023] In this document, when it is mentioned that the first component is located on the second component, this may mean that the first component can be directly formed on the second component, or a third component can be interposed between the first component and the second component. In addition, in the drawings, to effectively describe the technical content, the thickness of the components may be exaggerated or reduced.

[0024] In this document, when an element or layer is referred to as "being located on", "joined to", "connected to", "attached to", or "coupled to" another element or layer, it can be directly located on, joined, connected, attached, or coupled to the other element or layer, or there may be intermediate elements or layers. In contrast, when an element is referred to as "directly on another element or layer", "directly joined to", "directly connected to", "directly attached to", or "directly coupled to" another element or layer, there may be no intermediate elements or layers. Other words used to describe the relationship between elements should be interpreted in a similar manner (e.g., "between" vs. "directly between", "adjacent" vs. "directly adjacent", etc.). As used herein, the term "and / or" includes any and all combinations of one or more of the related listed items.

[0025] In this document, the exemplary embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. As used herein, expressions such as "at least one of..." modify the entire list of elements when following a list of elements, rather than modifying individual elements in the list. For example, the expression "at least one of a, b, and c" should be understood to include only a, only b, only c, both a and b, both a and c, both b and c, or all of a, b, and c.

[0026] The terms used herein are for describing particular exemplary configurations only and are not intended to be limiting. As used herein, the singular articles "a", "an", and "the" may also be intended to include the plural forms, unless clearly stated otherwise herein. The terms "comprising", "including", and "having" are inclusive and thus specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or their combinations. The method steps, processes, and operations described herein should not be construed as necessarily requiring them to be performed in the particular order discussed or shown, unless specifically identified as an order of performance. Additional or alternative steps may be employed.

[0027] As used herein, phrases such as "in one embodiment", "according to one embodiment", "in some embodiments", etc. generally refer to the fact that the particular feature, structure, or characteristic after such phrase may be included in at least one embodiment of the present disclosure. Thus, a particular feature, structure, or characteristic may be included in more than one embodiment of the present disclosure, such that these phrases do not necessarily refer to the same embodiment. As used herein, the terms "example", "exemplary", etc. are used "as an example, instance, or illustration. Any embodiment, aspect, or design described herein as "example" or "exemplary" is not necessarily to be construed as preferred or superior to other embodiments, aspects, or designs. Instead, the use of the terms "example", "exemplary", etc. is intended to present concepts in a concrete manner.

[0028] It has been found that as the manufacturing process in the semiconductor field develops towards smaller feature sizes, the requirements for defect detection technologies for wafers are also getting higher and higher. In order to ensure the production yield of chips and improve the detection throughput of chips, it is necessary to quickly and accurately scan the chips and ensure that defects of nanoscale dimensions can be scanned within a short time. Currently, the main means to accurately detect nanoscale defects is the dark field detection method, which detects nanoscale defects by collecting the stray light generated when the illumination beam irradiates the wafer surface. Therefore, the ellipticity of the illumination beam is crucial. The higher the ellipticity of the illumination beam, the higher the uniformity in all directions of the beam, and a higher system resolution can be obtained, enabling the detection of defect signals with smaller details. If the ellipticity of the beam is low, the beam size and divergence angle in the horizontal and vertical directions, and the stray light signals collected after passing through the complex optical system will also be affected.

[0029] Based on the above research, embodiments of the present disclosure provide an optical device and a laser beam shape adjustment method, which can improve the ellipticity of the laser beam, thereby improving the uniformity of the beam in all directions, obtaining a higher system resolution, making the detection of minute features and defects more sensitive, and using the first cylindrical lens group and the second cylindrical lens group to separately control the beam size and the beam waist position of the laser beam in the vertical direction and the horizontal direction, and the divergence angles of the laser beam in the vertical direction and the horizontal direction can be collimated and coincided through the collimating lens.

[0030] Regarding the defects existing in the above solutions, they are all the results obtained by the inventors through practice and careful research. Therefore, the discovery process of the above problems and the solutions proposed by the present disclosure in this article for the above problems should all be the contributions made by the inventors to the present disclosure during the process of the present disclosure.

[0031] It should be noted that similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0032] The following will describe in detail some embodiments of the present invention with reference to the drawings. Without conflict, the following embodiments and the features in the embodiments can be combined with each other.

[0033] As Figures 1 to 4As shown, at least one embodiment provides an optical device, which includes: a first cylindrical lens group 1, a second cylindrical lens group 2, a collimating lens 3, and a moving component 4; wherein the first cylindrical lens group 1 and the second cylindrical lens group 2 are respectively located between the laser and the collimating lens 3, and the first cylindrical lens group 1, the second cylindrical lens group 2, and the collimating lens 3 are respectively movably mounted on the moving component 4; when the laser emits a laser beam 5, the laser beam 5 is condensed by the first cylindrical lens group 1 on the vertical plane, and the laser beam 5 is condensed by the second cylindrical lens group 2 on the horizontal plane until the laser beam 5 is incident on the collimating lens 3, so that the collimating lens 3 collimates and corrects the laser beam 5; when the first cylindrical lens 11 in the first cylindrical lens group 1 moves relative to the second cylindrical lens 12 or the second cylindrical lens 12 moves relative to the first cylindrical lens 11 on the moving component 4, the divergence angle of the laser beam 5 after being condensed on the vertical plane is adjusted, and the first cylindrical lens group 1 moves relative to the collimating lens 3 on the moving component 4 until the focus point coincides with the focal length position of the collimating lens 3, and the angle size of the divergence angle is adjusted to change the diameter of the laser beam 5 emitted from the collimating lens 3 on the vertical plane; when the third cylindrical lens 21 in the second cylindrical lens group 2 moves relative to the fourth cylindrical lens 22 or the fourth cylindrical lens 22 moves relative to the third cylindrical lens 21 on the moving component 4, the divergence angle of the laser beam 5 after being condensed on the horizontal plane is adjusted, and the second cylindrical lens group 2 moves relative to the collimating lens 3 on the moving component 4 until the focus point coincides with the focal length position of the collimating lens 3, and the angle size of the divergence angle is adjusted to change the diameter of the laser beam 5 emitted from the collimating lens 3 on the horizontal plane.

[0034] Specifically, the component of the laser beam 5 on the vertical plane can be condensed by the first cylindrical lens group 1, while the component of the laser beam 5 on the vertical plane will directly pass through the second cylindrical lens group 2. Similarly, the component of the laser beam 5 on the horizontal plane can be condensed by the second cylindrical lens group 2, while the component of the laser beam 5 on the horizontal plane will directly pass through the first cylindrical lens group 1, thereby realizing that the first cylindrical lens group 1 and the second cylindrical lens group 2 respectively control the laser beam 5 in a single direction.

[0035] Specifically, by using a single collimating lens 3, the collimation of the laser beam 5 in two directions is achieved, and at the same time, the laser beam 5 with different divergence angles can be collimated and laser beams 5 of different sizes can be produced.

[0036] In at least one embodiment, by changing the positions of the first cylindrical lens 11 and the second cylindrical lens 12 in the first cylindrical lens group 1 and the positions of the third cylindrical lens 21 and the fourth cylindrical lens 22 in the second cylindrical lens group 2, the divergence angles of the laser beam 5 in the vertical and horizontal directions can be separately changed, and by adjusting the positions of the first cylindrical lens group 1, the second cylindrical lens group 2, and the collimating lens 3, the diameters of the laser beam 5 in the vertical and horizontal directions can be changed, and at the same time, parallel light can be emitted, meeting different requirements when detecting wafer defects, and realizing that the laser beam 5 detects smaller defect signals with optimal uniformity.

[0037] In at least one embodiment, referring to Figure 1 and Figure 2 , the cylindrical lens group 1 includes: a first cylindrical lens 11 and a second cylindrical lens 12; the first cylindrical lens 11 and the second cylindrical lens 12 are horizontally arranged and movably mounted on the moving component 4, and the cylindrical surface of the first cylindrical lens 11 faces the laser, the plane of the first cylindrical lens 11 faces the plane of the second cylindrical lens 12, and the cylindrical surface of the second cylindrical lens 12 faces the plane of the collimating lens 3; when the laser emits a laser beam 5 towards the first cylindrical lens 11, the laser beam 5 is condensed on the vertical plane by the first cylindrical lens 11 and the second cylindrical lens 12 until the laser beam 5 hits the collimating lens 3, so that the collimating lens 3 collimates and corrects the laser beam 5; when the first cylindrical lens 11 moves relative to the second cylindrical lens 12 or the second cylindrical lens 12 moves relative to the first cylindrical lens 11 on the moving component 4, the divergence angle of the laser beam 5 after being condensed on the vertical plane is adjusted, and the first cylindrical lens 11 and the second cylindrical lens 12 as a whole move relative to the collimating lens 3 on the moving component 4 until the focus point coincides with the focal length position of the collimating lens 3, so that the laser beam 5 emitted from the collimating lens 3 is parallel to the laser beam 5 emitted from the laser.

[0038] Specifically, the cylindrical surface of the first cylindrical lens 11 is the first side surface 111, and the plane of the first cylindrical lens 11 is the second side surface 112.

[0039] Specifically, when the vertical part of the laser beam 5 passes through the first side surface 111, its direction will change, and when the vertical part of the laser beam 5 passes through the second side surface 112, its direction will not change.

[0040] Specifically, when the horizontal part of the laser beam 5 passes through the first side surface 111, its direction will not change, and when the horizontal part of the laser beam 5 passes through the second side surface 112, its direction will not change.

[0041] Specifically, the plane of the second cylindrical lens 12 is the third side surface 121, and the cylindrical surface of the second cylindrical lens 12 is the fourth side surface 122.

[0042] Specifically, when the vertical part of the laser beam 5 passes through the third side surface 121, its direction will not change, and when the vertical part of the laser beam 5 passes through the fourth side surface 122, its direction will change.

[0043] Specifically, when the horizontal part of the laser beam 5 passes through the third side surface 121, its direction will not change, and when the horizontal part of the laser beam 5 passes through the fourth side surface 122, its direction will not change.

[0044] In at least one embodiment, referring to Figure 1 andFigure 3 The cylindrical lens group two 2 includes: a third cylindrical lens 21 and a fourth cylindrical lens 22; the third cylindrical lens 21 and the fourth cylindrical lens 22 are vertically arranged and movably mounted on the moving component 4, and the cylindrical surface of the third cylindrical lens 21 faces the laser, the plane of the third cylindrical lens 21 faces the plane of the fourth cylindrical lens 22, and the cylindrical surface of the fourth cylindrical lens 22 faces the plane of the collimating lens 3; when the laser emits a laser beam 5 towards the first cylindrical lens 11, the laser beam 5 is condensed horizontally by the first cylindrical lens 11 and the second cylindrical lens 12 until the laser beam 5 hits the collimating lens 3, so that the collimating lens 3 collimates and corrects the laser beam 5; when the third cylindrical lens 21 moves relative to the fourth cylindrical lens 22 or the fourth cylindrical lens 22 moves relative to the third cylindrical lens 21 on the moving component 4, the divergence angle of the laser beam 5 after being condensed horizontally is adjusted, and when the third cylindrical lens 21 and the fourth cylindrical lens 22 as a whole move relative to the collimating lens 3 on the moving component 4 until the focus point coincides with the focal length position of the collimating lens 3, the laser beam 5 emitted from the collimating lens 3 is parallel to the laser beam 5 emitted from the laser.

[0045] Specifically, the cylindrical surface of the third cylindrical lens 21 is the fifth side surface 211, and the plane of the first cylindrical lens 11 is the sixth side surface 212.

[0046] Specifically, the vertical part of the laser beam 5 does not change its direction when passing through the fifth side surface 211, and the vertical part of the laser beam 5 does not change its direction when passing through the sixth side surface 212.

[0047] Specifically, the horizontal part of the laser beam 5 changes its direction when passing through the fifth side surface 211, and the horizontal part of the laser beam 5 does not change its direction when passing through the sixth side surface 212.

[0048] Specifically, the plane of the fourth cylindrical lens 22 is the seventh side surface 221, and the cylindrical surface of the second cylindrical lens 12 is the eighth side surface 222.

[0049] Specifically, the vertical part of the laser beam 5 does not change its direction when passing through the seventh side surface 221, and the vertical part of the laser beam 5 does not change its direction when passing through the eighth side surface 222.

[0050] Specifically, the horizontal part of the laser beam 5 does not change its direction when passing through the seventh side surface 221, and the horizontal part of the laser beam 5 changes its direction when passing through the eighth side surface 222.

[0051] In at least one embodiment, the collimating lens 3 is provided with a spherical surface to collimate and correct the laser beam 5 emitted from the collimating lens 3, and the laser beam 5 emitted from the collimating lens 3 is parallel to the laser beam 5 emitted from the laser.

[0052] Specifically, the plane of the collimating mirror 3 is the ninth side surface 31, and the spherical surface of the collimating mirror 3 is the tenth side surface 32.

[0053] Specifically, when the vertical part of the laser beam 5 passes through the ninth side surface 31, its direction will not change, and when the vertical part of the laser beam 5 passes through the tenth side surface 32, its direction will change.

[0054] Specifically, when the horizontal part of the laser beam 5 passes through the ninth side surface 31, its direction will not change, and when the horizontal part of the laser beam 5 passes through the tenth side surface 32, its direction will change.

[0055] In at least one embodiment, determine the position of the collimating mirror 3 on the moving assembly 4 and the focal length of the collimating mirror 3; determine the diameter of the laser beam 5 emitted from the collimating mirror 3 on the vertical plane to obtain the divergence angle of the laser beam 5 after focusing on the vertical plane; determine the diameter of the laser beam 5 emitted from the laser on the vertical plane to obtain the focal length of the first cylindrical mirror group 1; configure the optical parameters of the first cylindrical mirror 11 and the second cylindrical mirror 12 and their positions on the moving assembly 4 according to the focal length of the first cylindrical mirror group 1.

[0056] Specifically, please refer to Figure 2 , according to the focal length of the collimating mirror 3 f 1 , and the diameter of the laser beam 5 emitted from the collimating mirror 3 on the vertical plane d 2 , the divergence angle size of the laser beam 5 after focusing on the vertical plane can be deduced from the formula θ 1 = arctan (d 2 / 2) / f 1 to be θ 1 . According to the diameter of the laser beam 5 emitted from the laser on the vertical plane d 1 , the focal length of the first cylindrical mirror group 1 can be deduced from the formula f 2 = d 1 / 2tan θ 1 to be f 2 . Through the focal length of the first cylindrical mirror group 1 f 2 the optical parameters of the first cylindrical mirror 11 and the second cylindrical mirror 12 and their positions on the moving assembly 4 can be configured.

[0057] Specifically, the optical parameters of the first cylindrical mirror 11 and the second cylindrical mirror 12 refer to the radius of curvature of the first side surface 111 and the radius of curvature of the fourth side surface 122.

[0058] In at least one embodiment, determine the position of the collimating mirror 3 on the moving component 4 and the focal length of the collimating mirror 3; determine the diameter of the laser beam 5 emitted from the collimating mirror 3 on the horizontal plane to obtain the divergence angle of the laser beam 5 after focusing on the horizontal plane; determine the diameter of the laser beam 5 emitted from the laser on the horizontal plane to obtain the focal length of the second cylindrical mirror group 2; configure the optical parameters of the third cylindrical mirror 21 and the fourth cylindrical mirror 22 and their positions on the moving component 4 according to the focal length of the second cylindrical mirror group 2.

[0059] Specifically, please refer to Figure 3 , according to the focal length of the collimating mirror 3 f 1 , and the diameter of the laser beam 5 emitted from the collimating mirror 3 on the vertical plane d 4 , the divergence angle of the laser beam 5 after focusing on the vertical plane can be deduced by the formula θ 2 = arctan (d 4 / 2) / f 1 to be θ 2 . According to the diameter of the laser beam 5 emitted from the laser on the vertical plane d 3 , the focal length of the first cylindrical mirror group 1 can be deduced by the formula f 3 = d 3 / 2tan θ 2 , and the focal length of the first cylindrical mirror group 1 can be deduced. f 3 . Through the focal length of the first cylindrical mirror group 1 f 3 the optical parameters of the third cylindrical mirror 21 and the fourth cylindrical mirror 22 and their positions on the moving component 4 can be configured.

[0060] Specifically, the optical parameters of the third cylindrical mirror 21 and the fourth cylindrical mirror 22 refer to the radius of curvature of the fifth side surface 211 and the radius of curvature of the eighth side surface 222.

[0061] Specifically, the ratio range (beam expansion multiple) of the diameter of the laser beam 5 emitted from the laser on the horizontal plane to the diameter of the laser beam 5 emitted from the collimating mirror 3 on the horizontal plane is 0.75 to 1.25.

[0062] Specifically, the ratio range (beam expansion multiple) of the diameter of the laser beam 5 emitted by the laser in the vertical plane to the diameter of the laser beam 5 emitted by the collimating mirror 3 in the vertical plane is from 0.75 to 1.25.

[0063] Specifically, when the beam expansion multiples of the laser beam 5 in both the horizontal plane and the vertical plane are 0.75, the radius of curvature of the first side 111 is 22.92 mm, the second side 112 is a plane, the third side 121 is a plane, and the radius of curvature of the fourth side 122 is 18.32 mm; the central thickness of the first cylindrical mirror 11 is 2.55 mm, and the central thickness of the second cylindrical mirror 12 is 2.7 mm; the central distance between the first cylindrical mirror 11 and the second cylindrical mirror 12 is 82.39 mm; the cylindrical mirror group 1 composed of the first cylindrical mirror 11 and the second cylindrical mirror 12 can independently control the divergence angle of the laser beam 5 in a single direction. The radius of curvature of the fifth side 211 is 45.85 mm, the sixth side 212 is a plane, the seventh side 221 is a plane, and the radius of curvature of the eighth side 222 is 11.45 mm; the central thickness of the third cylindrical mirror 21 is 2.27 mm, and the central thickness of the fourth cylindrical mirror 22 is 3.15 mm; the central distance between the third cylindrical mirror 21 and the fourth cylindrical mirror 22 is 115.33 mm; the cylindrical mirror group 2 composed of the third cylindrical mirror 21 and the fourth cylindrical mirror 22 can independently control the divergence angle of the laser beam 5 in another direction. The central distance between the cylindrical mirror group 1 and the cylindrical mirror group 2, that is, the distance between the second cylindrical mirror 12 and the third cylindrical mirror 21 is 161.85 mm; at the same time, in order to adapt to the variation range of the beam size, the apertures of all cylindrical mirrors are 10 mm; the ninth side 31 is a plane, and the radius of curvature of the tenth side 32 is 183.39 mm; the central distance of the collimating mirror 3 is 2.44 mm, and the central distance between the collimating mirror 3 and the fourth cylindrical mirror 22 is 510.49 mm; to ensure that the divergence angles of the light rays are within the light passing aperture of the collimating mirror 3, the aperture of the collimating mirror 3 is 25.4 mm.

[0064] Specifically, when the beam expansion multiples of the laser beam 5 in the horizontal plane and the vertical plane are both 1.25, the radius of curvature of the first side surface 111 is 22.92 mm, the second side surface 112 is a plane, the third side surface 121 is a plane, and the radius of curvature of the fourth side surface 122 is 18.32 mm; the central thickness of the first cylindrical mirror 11 is 2.55 mm, and the central thickness of the second cylindrical mirror 12 is 2.7 mm; the central distance between the first cylindrical mirror 11 and the second cylindrical mirror 12 is 84.72 mm; the cylindrical mirror group 1 composed of the first cylindrical mirror 11 and the second cylindrical mirror 12 can independently control the divergence angle of the laser beam 5 in a single direction. The radius of curvature of the fifth side surface 211 is 45.85 mm, the sixth side surface 212 is a plane, the seventh side surface 221 is a plane, and the radius of curvature of the eighth side surface 222 is 11.45 mm; the central thickness of the third cylindrical mirror 21 is 2.27 mm, and the central thickness of the fourth cylindrical mirror 22 is 3.15 mm; the central distance between the third cylindrical mirror 21 and the fourth cylindrical mirror 22 is 118.21 mm; the cylindrical mirror group 2 composed of the third cylindrical mirror 21 and the fourth cylindrical mirror 22 can independently control the divergence angle of the laser beam 5 in the other direction. The central distance between the cylindrical mirror group 1 and the cylindrical mirror group 2, that is, the distance between the second cylindrical mirror 12 and the third cylindrical mirror 21 is 51.66 mm; at the same time, in order to adapt to the variation range of the beam size, the apertures of all cylindrical mirrors are 10 mm; the ninth side surface 31 is a plane, and the radius of curvature of the tenth side surface 32 is 183.39 mm; the central distance of the collimating mirror 3 is 2.44 mm, and the central distance between the collimating mirror 3 and the fourth cylindrical mirror 22 is 461.61 mm; to ensure that the divergence angles of the light rays are within the light passing aperture of the collimating mirror 3, the aperture of the collimating mirror 3 is 25.4 mm.

[0065] Specifically, please refer to Figure 4 , Figure 4 In the left figure of, the beam expansion ratio of the laser beam 5 in the horizontal direction is 1.25, and the beam expansion ratio in the vertical direction is 0.75. In the right figure, the beam expansion ratio of the laser beam 5 in the horizontal direction is 1, and the beam expansion ratio in the vertical direction is 1.

[0066] In at least one embodiment, the moving assembly 4 includes: a moving track 41; the cylindrical mirror group 1, the cylindrical mirror group 2, and the collimating mirror 3 are respectively snap-fitted and installed on the moving track 41.

[0067] Based on the same inventive concept, at least one embodiment further provides a method for adjusting the shape of a laser beam as described above, which includes: when the laser emits a laser beam 5, the laser beam 5 is focused in the vertical plane by the first cylindrical lens group 1, and the laser beam 5 is focused in the horizontal plane by the second cylindrical lens group 2 until the laser beam 5 hits the collimating mirror 3, so that the collimating mirror 3 collimates and corrects the laser beam 5; when the first cylindrical lens 11 in the first cylindrical lens group 1 moves relative to the second cylindrical lens 12 or the second cylindrical lens 12 moves relative to the first cylindrical lens 11 on the moving assembly 4, the divergence angle of the laser beam 5 after being focused in the vertical plane is adjusted, and the first cylindrical lens group 1 moves relative to the collimating mirror 3 on the moving assembly 4 until the focal point coincides with the focal length position of the collimating mirror 3, and the angle size of the divergence angle is adjusted to change the diameter of the laser beam 5 emitted from the collimating mirror 3 in the vertical plane; when the third cylindrical lens 21 in the second cylindrical lens group 2 moves relative to the fourth cylindrical lens 22 or the fourth cylindrical lens 22 moves relative to the third cylindrical lens 21 on the moving assembly 4, the divergence angle of the laser beam 5 after being focused in the horizontal plane is adjusted, and the second cylindrical lens group 2 moves relative to the collimating mirror 3 on the moving assembly 4 until the focal point coincides with the focal length position of the collimating mirror 3, and the angle size of the divergence angle is adjusted to change the diameter of the laser beam 5 emitted from the collimating mirror 3 in the horizontal plane.

[0068] In at least one embodiment, determine the position of the collimating mirror 3 on the moving assembly 4 and the focal length of the collimating mirror 3; determine the diameter of the laser beam 5 emitted from the collimating mirror 3 in the vertical plane to obtain the divergence angle of the laser beam 5 after being focused in the vertical plane; determine the diameter of the laser beam 5 emitted by the laser in the vertical plane to obtain the focal length of the first cylindrical lens group 1; configure the optical parameters and the position on the moving assembly 4 of the first cylindrical lens 11 and the second cylindrical lens 12 through the focal length of the first cylindrical lens group 1.

[0069] In at least one embodiment, determine the position of the collimating mirror 3 on the moving assembly 4 and the focal length of the collimating mirror 3; determine the diameter of the laser beam 5 emitted from the collimating mirror 3 in the horizontal plane to obtain the divergence angle of the laser beam 5 after being focused in the horizontal plane; determine the diameter of the laser beam 5 emitted by the laser in the horizontal plane to obtain the focal length of the second cylindrical lens group 2; configure the optical parameters and the position on the moving assembly 4 of the third cylindrical lens 21 and the fourth cylindrical lens 22 through the focal length of the second cylindrical lens group 2.

[0070] In summary, through the change of the positions of the first cylindrical lens and the second cylindrical lens in the first cylindrical lens group and the positions of the third cylindrical lens and the fourth cylindrical lens in the second cylindrical lens group, the present invention can separately change the divergence angles of the laser beam in the vertical and horizontal directions, and by adjusting the positions of the first cylindrical lens group, the second cylindrical lens group and the collimating mirror, it is possible to change the diameters of the laser beam in the vertical and horizontal directions, and at the same time, it is also possible to achieve parallel light output, meeting different requirements when detecting wafer defects, and realizing the detection of smaller defect signals with the optimal uniformity of the laser beam.

[0071] In the description of the embodiments of the present invention, unless otherwise clearly defined and limited, the terms "installed", "connected", and "coupled" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0072] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation to the present invention. In addition, terms such as "first", "second" and other numerical terms used herein do not imply an order or sequence unless clearly indicated herein. Therefore, without departing from the teachings of the exemplary embodiments, the first element, component, region, layer or section discussed above may be referred to as the second element, component, region, layer or section.

[0073] Spatially relative terms, such as "inner", "outer", "below", "beneath", "lower", "above", "upper", etc., may be used herein to facilitate describing one element or feature's relationship to another element or feature as illustrated in the figures. In addition to the orientation depicted in the figures, spatially relative terms are intended to encompass different orientations of the device in use or operation. For example, if the device in the figures is turned over, an element described as "below" or "beneath" another element or feature will then be oriented "above" the other element or feature. Thus, the exemplary term "below" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations), and the spatially relative descriptors used herein are interpreted accordingly.

[0074] In the above discussion, unless otherwise stated, when used to describe a numerical value, the terms "about", "approximately", "substantially", etc. mean a variation of + / −10% of that value.

[0075] Taking the above-mentioned ideal embodiments of the present invention as an inspiration, through the above description, relevant staff can completely make various changes and modifications without departing from the technical idea of this invention. The technical scope of this invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. An optical device, characterized in that, Including: A first cylindrical lens group (1), a second cylindrical lens group (2), a collimating lens (3) and a moving component (4); wherein The first cylindrical lens group (1) and the second cylindrical lens group (2) are respectively located between the laser and the collimating lens (3), and the first cylindrical lens group (1), the second cylindrical lens group (2) and the collimating lens (3) are respectively movably mounted on the moving component (4); When the laser emits a laser beam (5), the laser beam (5) is condensed on the vertical plane by the first cylindrical lens group (1), and the laser beam (5) is condensed on the horizontal plane by the second cylindrical lens group (2) until the laser beam (5) hits the collimating lens (3), so that the collimating lens (3) collimates and corrects the laser beam (5); When the first cylindrical lens (11) in the first cylindrical lens group (1) moves relative to the second cylindrical lens (12) or the second cylindrical lens (12) moves relative to the first cylindrical lens (11) on the moving component (4), the divergence angle of the laser beam (5) after being condensed on the vertical plane is adjusted. The first cylindrical lens group (1) moves relative to the collimating lens (3) on the moving component (4) until the focal point coincides with the focal length position of the collimating lens (3), and the angle size of the divergence angle is adjusted to change the diameter of the laser beam (5) emitted from the collimating lens (3) on the vertical plane; When the third cylindrical lens (21) in the second cylindrical lens group (2) moves relative to the fourth cylindrical lens (22) or the fourth cylindrical lens (22) moves relative to the third cylindrical lens (21) on the moving component (4), the divergence angle of the laser beam (5) after being condensed on the horizontal plane is adjusted. The second cylindrical lens group (2) moves relative to the collimating lens (3) on the moving component (4) until the focal point coincides with the focal length position of the collimating lens (3), and the angle size of the divergence angle is adjusted to change the diameter of the laser beam (5) emitted from the collimating lens (3) on the horizontal plane.

2. The optical device according to claim 1, wherein The first cylindrical lens group (1) includes: a first cylindrical lens (11) and a second cylindrical lens (12); The first cylindrical lens (11) and the second cylindrical lens (12) are horizontally arranged and movably mounted on the moving component (4), and the cylindrical surface of the first cylindrical lens (11) faces the laser, the plane of the first cylindrical lens (11) faces the plane of the second cylindrical lens (12), and the cylindrical surface of the second cylindrical lens (12) faces the plane of the collimating lens (3); When the laser emits a laser beam (5) towards the first cylindrical lens (11), the laser beam (5) is condensed on the vertical plane by the first cylindrical lens (11) and the second cylindrical lens (12) until the laser beam (5) hits the collimating lens (3), so that the collimating lens (3) collimates and corrects the laser beam (5); When the first cylindrical mirror (11) moves relative to the second cylindrical mirror (12) or the second cylindrical mirror (12) moves relative to the first cylindrical mirror (11) on the moving component (4), the divergence angle of the laser beam (5) after focusing on the vertical plane is adjusted, and the first cylindrical mirror (11) and the second cylindrical mirror (12) as a whole move relative to the collimating mirror (3) on the moving component (4) until the focal point coincides with the focal length position of the collimating mirror (3), so that the laser beam (5) emitted from the collimating mirror (3) is parallel to the laser beam (5) emitted from the laser.

3. The optical device according to claim 1, wherein the second cylindrical mirror group (2) includes: a third cylindrical mirror (21) and a fourth cylindrical mirror (22); the third cylindrical mirror (21) and the fourth cylindrical mirror (22) are vertically arranged and movably installed on the moving component (4), the cylindrical surface of the third cylindrical mirror (21) faces the laser, the plane of the third cylindrical mirror (21) faces the plane of the fourth cylindrical mirror (22), and the cylindrical surface of the fourth cylindrical mirror (22) faces the plane of the collimating mirror (3); when the laser emits the laser beam (5) towards the first cylindrical mirror (11), the laser beam (5) is focused horizontally by the first cylindrical mirror (11) and the second cylindrical mirror (12) until the laser beam (5) hits the collimating mirror (3), so that the collimating mirror (3) collimates and corrects the laser beam (5); When the third cylindrical mirror (21) moves relative to the fourth cylindrical mirror (22) or the fourth cylindrical mirror (22) moves relative to the third cylindrical mirror (21) on the moving component (4), the divergence angle of the laser beam (5) after focusing on the horizontal plane is adjusted, and when the third cylindrical mirror (21) and the fourth cylindrical mirror (22) as a whole move relative to the collimating mirror (3) on the moving component (4) until the focal point coincides with the focal length position of the collimating mirror (3), the laser beam (5) emitted from the collimating mirror (3) is parallel to the laser beam (5) emitted from the laser.

4. The optical device according to claim 1, wherein a spherical surface is provided on the collimating mirror (3) to collimate and correct the laser beam (5) emitted from the collimating mirror (3), and the laser beam (5) emitted from the collimating mirror (3) is parallel to the laser beam (5) emitted from the laser.

5. The optical device according to claim 1, wherein determine the position of the collimating mirror (3) on the moving component (4) and the focal length of the collimating mirror (3); determine the diameter of the laser beam (5) emitted from the collimating mirror (3) on the vertical plane to obtain the divergence angle of the laser beam (5) after focusing on the vertical plane; determine the diameter of the laser beam (5) emitted from the laser on the vertical plane to obtain the focal length of the first cylindrical mirror group (1); configure the optical parameters of the first cylindrical mirror (11) and the second cylindrical mirror (12) and their positions on the moving component (4) according to the focal length of the first cylindrical mirror group (1).

6. The optical device according to claim 1, wherein Determine the position of the collimating mirror (3) on the moving component (4) and the focal length of the collimating mirror (3); Determine the diameter of the laser beam (5) emitted from the collimating mirror (3) on the horizontal plane to obtain the divergence angle after the laser beam (5) is focused on the horizontal plane; Determine the diameter of the laser beam (5) emitted from the laser on the horizontal plane to obtain the focal length of the second cylindrical mirror group (2); Configure the optical parameters of the third cylindrical mirror (21) and the fourth cylindrical mirror (22) and their positions on the moving component (4) according to the focal length of the second cylindrical mirror group (2).

7. The optical device according to claim 1, wherein the moving component (4) includes: a moving track (41); the first cylindrical mirror group (1), the second cylindrical mirror group (2), and the collimating mirror (3) are respectively snap-mounted on the moving track (41).

8. A laser beam shape adjustment method using the method according to any one of claims 1-7, characterized in that, including: When the laser emits the laser beam (5), the laser beam (5) is focused on the vertical plane by the first cylindrical mirror group (1), and the laser beam (5) is focused on the horizontal plane by the second cylindrical mirror group (2) until the laser beam (5) hits the collimating mirror (3) so that the collimating mirror (3) collimates and corrects the laser beam (5); When the first cylindrical mirror (11) in the first cylindrical mirror group (1) moves relative to the second cylindrical mirror (12) or the second cylindrical mirror (12) moves relative to the first cylindrical mirror (11) on the moving component (4), the divergence angle after the laser beam (5) is focused on the vertical plane is adjusted. The first cylindrical mirror group (1) moves relative to the collimating mirror (3) on the moving component (4) until the focal point coincides with the focal length position of the collimating mirror (3), and the angle of the divergence angle is adjusted to change the diameter of the laser beam (5) emitted from the collimating mirror (3) on the vertical plane; When the third cylindrical mirror (21) in the second cylindrical mirror group (2) moves relative to the fourth cylindrical mirror (22) or the fourth cylindrical mirror (22) moves relative to the third cylindrical mirror (21) on the moving component (4), the divergence angle after the laser beam (5) is focused on the horizontal plane is adjusted. The second cylindrical mirror group (2) moves relative to the collimating mirror (3) on the moving component (4) until the focal point coincides with the focal length position of the collimating mirror (3), and the angle of the divergence angle is adjusted to change the diameter of the laser beam (5) emitted from the collimating mirror (3) on the horizontal plane.

9. The method for adjusting the shape of the laser beam according to claim 8, wherein determine the position of the collimating mirror (3) on the moving component (4) and the focal length of the collimating mirror (3); determine the diameter of the laser beam (5) emitted from the collimating mirror (3) on the vertical plane to obtain the divergence angle after the laser beam (5) is focused on the vertical plane; determine the diameter of the laser beam (5) emitted from the laser on the vertical plane to obtain the focal length of the first cylindrical mirror group (1); configure the optical parameters of the first cylindrical mirror (11) and the second cylindrical mirror (12) and their positions on the moving component (4) according to the focal length of the first cylindrical mirror group (1).

10. The method for adjusting the shape of the laser beam according to claim 8, wherein determine the position of the collimating mirror (3) on the moving component (4) and the focal length of the collimating mirror (3); Determine the diameter of the laser beam (5) emitted from the collimator (3) on the horizontal plane to obtain the divergence angle of the laser beam (5) after focusing on the horizontal plane; Determine the diameter of the laser beam (5) emitted from the laser on the horizontal plane to obtain the focal length of the second cylindrical lens group (2); Configure the optical parameters of the third cylindrical lens (21) and the fourth cylindrical lens (22) and their positions on the moving component (4) according to the focal length of the second cylindrical lens group (2).

Images