Defect inspection device

Abstract

A defect inspection apparatus includes: first, second, and third units that irradiate a sample holder with first, second, and third inspection light, respectively; a camera including a single image sensor that generates an image of the sample moving linearly on the sample holder using time delay integration; and a detector that detects a defect of the sample based on the first image, the second image, and the third image provided by the camera, in which the first inspection light, the second inspection light, and the third inspection light are simultaneously irradiated to the sample holder, and in which the single image sensor includes: a first portion, a second portion, and a third portion, the first portion generates a first image of the sample captured by the first inspection light, the second portion generates a second image of the sample captured by the second inspection light, and the third portion generates a third image of the sample captured by the third inspection light.

Description

[0001] This application claims priority to and all benefits derived from Korean Patent Application No. 10-2023-0121384, filed on September 12, 2023, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0002] The embodiment relates to a structure of a defect inspection apparatus. Background Art

[0003] Devices for capturing a sample using a camera and inspecting defects of the sample are variously used. Summary of the invention

[0004] However, as the structure of a sample to be inspected, such as a high-resolution display, becomes increasingly complex, the time required to detect defects using an inspection apparatus increases, and there is a space limitation for designing the structure of a defect inspection apparatus.

[0005] Embodiments include structures of defect inspection devices.The above-mentioned features are merely examples, and the present disclosure is not limited thereto.

[0006] Additional features will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments of the disclosure.

[0007] In an embodiment of the present disclosure, a defect inspection device includes: a first unit that irradiates a first inspection light onto a sample holder; a second unit that irradiates a second inspection light onto the sample holder; a third unit that irradiates a third inspection light onto the sample holder; a camera that includes a single image sensor that uses time delay integration to generate an image of a sample, the sample is set on the sample holder and moves linearly; and a detector that detects defects of the sample based on a first image, a second image, and a third image provided by the camera, wherein the first inspection light, the second inspection light, and the third inspection light are irradiated onto the sample holder at the same time, and wherein the single image sensor includes a first part, a second part, and a third part, the first part generates a first image of the sample captured by the first inspection light, the second part generates a second image of the sample captured by the second inspection light, and the third part generates a third image of the sample captured by the third inspection light.

[0008] In an embodiment, the first unit may include: a first light source that emits a first light; a first shielding plate that is disposed on a path of the first light from the first light source toward a sample holder and blocks a portion of the first light; and a first spatial filter that is disposed on the path of the first light and between the first shielding plate and the sample holder.

[0009] In an embodiment, the second unit may include: a second light source that emits a second light; a second shielding plate that is disposed on a path of the second light from the second light source toward the sample holder and blocks a portion of the second light; and a second spatial filter that is disposed on the path of the second light and between the second shielding plate and the sample holder.

[0010] In an embodiment, the third unit may include: a third light source that emits a third light; a third shielding plate that is disposed on a path of the third light from the third light source toward the sample holder and blocks a portion of the third light; and a third spatial filter that is disposed on the path of the third light and between the third shielding plate and the sample holder.

[0011] In an embodiment, the irradiation area of ​​the first inspection light, the irradiation area of ​​the second inspection light, and the irradiation area of ​​the third inspection light may be different from each other by a first shielding plate, a second shielding plate, and a third shielding plate, respectively.

[0012] In an embodiment, the irradiation area of ​​the first inspection light, the irradiation area of ​​the second inspection light, and the irradiation area of ​​the third inspection light may not overlap with each other on the sample holder.

[0013] In an embodiment, each of the first shielding plate, the second shielding plate, and the third shielding plate may include a non-reflective coating plate.

[0014] In an embodiment, the first spatial filter, the second spatial filter and the third spatial filter may respectively include apertures of different shapes.

[0015] In an embodiment, the defect inspection device may further include: at least one lens group disposed between the first to third units and the sample holder, wherein each of the first inspection light, the second inspection light, and the third inspection light may pass through the at least one lens group and irradiate toward the sample holder.

[0016] In an embodiment, the defect inspection device may further include: a sensor side optical filter, through which light reflected from the surface of the sample among the first inspection light, light reflected from the surface of the sample among the second inspection light, and light reflected from the surface of the sample among the third inspection light pass, wherein the sensor side optical filter may be adjacent to the camera.

[0017] In an embodiment, light reflected from the surface of the sample among the first inspection light, light reflected from the surface of the sample among the second inspection light, and light reflected from the surface of the sample among the third inspection light can be bent by a beam splitter to advance toward the sensor-side optical filter.

[0018] In an embodiment, the camera may generate a first image of the sample based on the signal obtained from the first portion, a second image of the sample based on the signal obtained from the second portion, and a third image of the sample based on the signal obtained from the third portion.

[0019] In an embodiment, when a defect is included in the sample, an image of the defect included in the first image, an image of the defect included in the second image, and an image of the defect included in the third image may be different from each other.

[0020] In an embodiment, the first image may include an image in which the defect appears relatively bright and the surrounding environment of the defect appears relatively dark, the second image may include an image in which the defect appears relatively dark and the surrounding environment of the defect appears relatively bright, and the third image may include an image in which the defect appears relatively three-dimensional.

[0021] In an embodiment, the detector may detect a location of a defect based on the first image, the second image, and the third image.

[0022] In an embodiment, the single image sensor may further include a dummy portion disposed between two adjacent portions among the first portion, the second portion, and the third portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above and other features and advantages of illustrative embodiments of the present disclosure will become more apparent through the following description taken in conjunction with the accompanying drawings, in which:

[0024] Figure 1 is a schematic diagram of an embodiment of the structure of a defect inspection device;

[0025] Figure 2 is incident on Figure 1 Schematic diagram of the first to third inspection lights of the sample holder;

[0026] Figure 3 is Figure 1 A plan view of an image sensor provided in a camera;

[0027] Figure 4A is from Figure 1 A schematic diagram of the structure of the first unit to the sample holder;

[0028] Figure 4B is from Figure 1 A schematic diagram of the structure of the second unit to the sample holder;

[0029] Figure 4C is from Figure 1 A schematic diagram of the structure of the third unit to the sample holder;

[0030] Figure 5Ais a schematic plan view of an embodiment of a first spatial filter;

[0031] Figure 5B is a schematic plan view of an embodiment of a sensor-side optical filter;

[0032] Figure 5C is a schematic plan view of an embodiment of a second spatial filter;

[0033] Figure 5D is a schematic plan view of an embodiment of a third spatial filter; and

[0034] Figure 6 This is a conceptual diagram for explaining an embodiment of time delay integration (TDI) image generation by an image sensor of a camera of a defect inspection device. DETAILED DESCRIPTION

[0035] Reference will now be made to the embodiments in detail, and the illustrative embodiments of the embodiments are illustrated in the accompanying drawings, wherein the same reference numerals always refer to the same elements. In this regard, the illustrated embodiments may have different forms and should not be construed as being limited to the description set forth herein. Accordingly, the following only describes the embodiments by reference to the drawings drawn to illustrate the features described. As used in this article, the term "and / or" includes any combination and all combinations of one or more of the related listed items. Throughout the disclosure, the statement "at least one of a, b, and c" indicates only a, only b, only c, both a and b, both a and c, both b and c, all of a, b, and c, or variations thereof.

[0036] Since the present disclosure allows various changes and many embodiments, the illustrative embodiments will be illustrated in the drawings and described in the written description. The effects and features of the present disclosure and the methods for achieving them will be explained with reference to the embodiments described in detail below with reference to the drawings. However, the present disclosure is not limited to the following embodiments and can be implemented in various forms.

[0037] Hereinafter, embodiments will be described with reference to the accompanying drawings, wherein like reference numerals refer to like elements throughout and repeated descriptions thereof will be omitted.

[0038] Although such terms as "first" and "second" may be used to describe various elements, such elements must not be limited to the above terms. The above terms are used to distinguish one element from another.

[0039] As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

[0040] It will be understood that the terms “comprises,” “comprising,” and / or variations thereof as used herein specify the presence of stated features or elements, but do not preclude the addition of one or more other features or elements.

[0041] It will be further understood that when a layer, region or element is referred to as being “on” another layer, region or element, it can be directly or indirectly on the other layer, region or element. That is, for example, intervening layers, regions or elements may be present.

[0042] For convenience of explanation, the size of the elements in the drawings may be exaggerated or reduced. As an example, for convenience of description, the size and thickness of each element shown in the drawings are arbitrarily represented, and therefore, the present disclosure is not necessarily limited thereto.

[0043] Where the illustrative embodiments may be implemented differently, the predetermined order of processes may be performed in an order different from the order described. As an example, two processes described in succession may be performed substantially simultaneously and in reverse order.

[0044] In the specification, "A and / or B" means A or B or A and B. In addition, "at least one of A and B" means A or B or A and B.

[0045] It will be understood that when a layer, region, or element is referred to as being “connected” to another layer, region, or element, it may be “directly connected” to the other layer, region, or element, or may be “indirectly connected” to the other layer, region, or element with the other layer, region, or element interposed therebetween. For example, it will be understood that when a layer, region, or element is referred to as being “electrically connected” to another layer, region, or element, it may be “directly electrically connected” to the other layer, region, or element, or may be “indirectly electrically connected” to the other layer, region, or element with the other layer, region, or element interposed therebetween.

[0046] The x-axis, y-axis, and z-axis are not limited to the three axes of the rectangular coordinate system and can be interpreted in a broader sense. For example, the x-axis, y-axis, and z-axis can be perpendicular to each other, or can represent different orientations that are not perpendicular to each other.

[0047] Figure 1 is a schematic diagram of an embodiment of the structure of a defect inspection device, Figure 2 is incident on Figure 1 Schematic diagram of the first to third inspection light of the sample holder, and Figure 3 is provided to Figure 1 A plan view of the image sensor of a camera.

[0048] Reference Figure 1The defect inspection device 1 (hereinafter, also referred to as the inspection device) is a device for inspecting defects of a sample SP that moves linearly, and can pick up a plurality of images of the sample SP to inspect defects using images.

[0049] The inspection device 1 may include a first unit (also referred to as a first light emitter) 10 that outputs a first inspection light ISL1, a second unit (also referred to as a second light emitter) 20 that outputs a second inspection light ISL2, and a third unit (also referred to as a third light emitter) 30 that outputs a third inspection light ISL3. The first inspection light ISL1, the second inspection light ISL2, and the third inspection light ISL3 outputted from the first unit 10, the second unit 20, and the third unit 30, respectively, may be irradiated toward the sample holder 71 at the same time. The sample SP (refer to Figure 2 ) can be set on the sample holder 71, and the sample holder 71 can be linearly moved by the moving part 73. Because the sample SP (refer to Figure 2 ) is fixedly arranged on the sample holder 71, and the sample holder 71 is linearly moved by the moving part 73, so in the specification, the sample SP (refer to Figure 2 ) can represent the linear movement of the sample holder 71.

[0050] The first inspection light ISL1 output from the first unit 10 may pass through at least one lens group (e.g., the first lens group 43 and the second lens group 45) disposed between the first unit 10 to the third unit 30 and the sample holder 71, and be irradiated toward the sample holder 71. The first beam splitter 41 may be disposed between the first unit 10 and the first lens group 43, and the first inspection light ISL1 may pass through the first beam splitter 41 and proceed toward the first lens group 43. The first inspection light ISL1 may proceed toward the sample holder 71 on a line coaxial with the optical axes of the first lens group 43 and the second lens group 45. Each of the first lens group 43 and the second lens group 45 may include one or more lenses.

[0051] The second inspection light ISL2 output from the second unit 20 may pass through the first lens group 43 and the second lens group 45 and be irradiated toward the sample holder 71. The second beam splitter 42 and the first beam splitter 41 may be disposed between the second unit 20 and the first lens group 43.

[0052] The second inspection light ISL2 may be bent by the first beam splitter 41. In an embodiment, the second inspection light ISL2 may pass through the second beam splitter 42, proceed toward the first beam splitter 41, and be reflected by the first beam splitter 41 to proceed toward the first lens group 43. The second inspection light ISL2 may proceed toward the sample holder 71 on a line coaxial with the optical axes of the first lens group 43 and the second lens group 45.

[0053] The third inspection light ISL3 output from the third unit 30 may pass through the first lens group 43 and the second lens group 45 and be irradiated toward the sample holder 71. The second beam splitter 42 and the first beam splitter 41 may be disposed between the third unit 30 and the first lens group 43.

[0054] The third inspection light ISL3 may be bent by the second beam splitter 42 and the first beam splitter 41. The third inspection light ISL3 may be reflected by the second beam splitter 42, travel toward the first beam splitter 41, and reflected by the first beam splitter 41 to travel toward the first lens group 43. Through the second beam splitter 42 and the first beam splitter 41, the third inspection light ISL3 may travel toward the sample holder 71 on a line coaxial with the optical axes of the first lens group 43 and the second lens group 45.

[0055] The first inspection light ISL1 , the second inspection light ISL2 , and the third inspection light ISL3 may be coaxial light traveling toward the sample holder 71 on a line coaxial with the optical axes of the first lens group 43 and the second lens group 45 .

[0056] The first inspection light ISL1, the second inspection light ISL2, and the third inspection light ISL3 may be irradiated toward the sample holder 71 respectively and simultaneously, and irradiate different areas on the sample holder 71. Figure 2 As shown in , the first inspection light ISL1 may irradiate the first area S1 of the sample holder 71, the second inspection light ISL2 may irradiate the second area S2 of the sample holder 71, and the third inspection light ISL3 may irradiate the third area S3 of the sample holder 71. The first area S1, which is the irradiation area of ​​the first inspection light ISL1, the second area S2, which is the irradiation area of ​​the second inspection light ISL2, and the third area S3, which is the irradiation area of ​​the third inspection light ISL3, may be different from each other by the first shielding plate 15, the second shielding plate 25, and the third shielding plate 35, respectively. In an embodiment, the first area S1, the second area S2, and the third area S3 may be adjacent to each other and may not overlap with each other.

[0057] Due to the linear movement of the sample holder 71, the sample SP can pass through the first area S1, the second area S2, and the third area S3. The sample holder 71 moves linearly, and the positions of the areas irradiated by the first inspection light ISL1, the second inspection light ISL2, and the third inspection light ISL3 (i.e., the first area S1, the second area S2, and the third area S3) are fixed. Figure 2 In the case of traveling in the horizontal direction, the sample SP may pass through the third region S3, the second region S2, and the first region S1 at different times.

[0058] When the sample SP passes through the third region S3, the second region S2, and the first region S1, light reflected by the surface of the sample SP may pass through Figure 1 4 and the sensor-side optical filter 55 shown in FIG. 4 , and is directed to the camera 60. In an embodiment, the light reflected by the sample SP may pass through the object portion 47, be bent by the third beam splitter 51 to proceed to the third lens group 52 and the fourth lens group 53, be bent by the image mirror 54, may pass through the sensor-side optical filter 55 and the image tube lens 56, and be directed to the camera 60. The sensor-side optical filter 55 may be adjacent to the camera 60.

[0059] The camera 60 includes a single image sensor, and the image sensor may include multiple parts that receive different light. Figure 3 As shown in FIG. 1 , the image sensor 100 may include a first portion 110 , a second portion 120 , and a third portion 130 , each having a preset area and spaced apart from each other.

[0060] Each of the first portion 110, the second portion 120, and the third portion 130 may include a plurality of pixels that may receive light. In an embodiment, the first portion 110 includes a plurality of pixel lines, and each pixel line may include pixels P arranged in one direction. Similarly, each of the second portion 120 and the third portion 130 may have a structure of a pixel line. In an embodiment, each pixel P may be approximately 5 micrometers (μm) × 5 micrometers (μm) ((width) × (height)). However, the above numbers are examples, and the size of the pixel may be variously changed.

[0061] The image sensor 100 may include a dummy portion 140 corresponding to a gap between two adjacent portions among the first portion 110, the second portion 120, and the third portion 130. In an embodiment, the image sensor 100 may include one dummy portion 140 between the first portion 110 and the second portion 120 and another dummy portion 140 between the second portion 120 and the third portion 130. The dummy portion 140 includes a pixel P, but may not generate an image (or signal) for inspecting defects of the sample SP.

[0062] The first part 110 can be inspected using the first inspection light ISL1 (refer to Figure 2 ) and by receiving the light reflected by the sample SP to scan the sample SP, the second part 120 can use the second inspection light ISL2 (refer to Figure 2 ) and scans the sample SP by receiving the light reflected by the sample SP, and the third part 130 can use the third inspection light ISL3 (refer to Figure 2 ) and scans the sample SP by receiving the light reflected by the sample SP. Figure 2 ) and the third inspection light ISL3 (reference Figure 2) may not be received by the first portion 110, and the third inspection light ISL3 (reference Figure 2 ) and the first inspection light ISL1 (reference Figure 2 ) may not be received by the second portion 120, and may be received by the first inspection light ISL1 (reference Figure 2 ) and the second inspection light ISL2 (reference Figure 2 )The light obtained may not be received by the third part 130.

[0063] The image sensor 100 may generate an image of the sample SP moving on the sample holder 71 using time delay integration ("TDI"). With respect to the same sample SP, the first part 110 may generate a first image, the second part 120 may generate a second image, and the third part 130 may generate a third image. When a defect is included in the sample SP, the image of the defect included in the first image, the image of the defect included in the second image, and the image of the defect included in the third image may be different from each other.

[0064] The first image obtained by the first inspection light ISL1 output from the first unit 10 may be formed by light received by the first portion 110. In an embodiment, in the first image, a defect of the sample SP may appear relatively bright, and a surrounding environment of the defect may appear relatively dark.

[0065] The second image obtained by the second inspection light ISL2 output from the second unit 20 may be formed by light received by the second portion 120. In an embodiment, in the second image, a defect of the sample SP may appear relatively dark, and a surrounding environment of the defect may appear relatively bright.

[0066] The third image obtained by the third inspection light ISL3 output from the third unit 30 may be formed by the light received by the third portion 130. In an embodiment, in the third image, defects of the sample SP may appear relatively three-dimensional.

[0067] like Figure 2 As shown in FIG, when the sample SP passes through the first, second, and third regions S1, S2, and S3, a single image sensor 100 may generate a plurality of images, such as first, second, and third images, through the first, second, and third portions 110, 120, and 130.

[0068] The above-described images, for example, the first image, the second image, and the third image may be provided to the detector 80 , and the detector 80 may detect defects of the sample SP based on the first to third images.

[0069] Figure 4A is from Figure 1 Schematic diagram of the structure of the first unit to the sample holder, Figure 4Bis from Figure 1 A schematic diagram of the structure of the second unit to the sample holder, and Figure 4C is from Figure 1 Schematic diagram of the structure of the third unit to the sample holder. In addition, Figure 5A is a schematic plan view of an embodiment of a first spatial filter, Figure 5B is a schematic plan view of an embodiment of a sensor-side optical filter, Figure 5C is a schematic plan view of an embodiment of a second spatial filter, and Figure 5D : is a schematic plan view of an embodiment of the third spatial filter. For ease of description, FIG. 4A to FIG. 4C Show omitted Figure 1 elements of the first beam splitter 41 and the second beam splitter 42 .

[0070] Reference Figures 1 to 4A , the first unit 10 may include a first shielding plate 15 disposed between the first light source 11 and the first spatial filter 19. In an embodiment, the first light source 11 may emit a first light (e.g., white light). The first unit 10 may include a 1-1 lens group 13 between the first light source 11 and the first shielding plate 15, and a 1-2 lens group 17 between the first shielding plate 15 and the first spatial filter 19. In other words, the first unit 10 may include a 1-1 lens group 13, a first shielding plate 15, a 1-2 lens group 17, and a first spatial filter 19 disposed on a forward path of the first light emitted from the first light source 11 from the first light source 11 toward the sample holder 71. The first spatial filter 19 may be disposed between the first shielding plate 15 and the sample holder 71.

[0071] Each of the 1-1 lens group 13 and the 1-2 lens group 17 may include one or more lenses. The first light emitted from the first light source 11 may pass through the 1-1 lens group 13, pass through the first shielding plate 15 between the 1-1 lens group 13 and the 1-2 lens group 17, and travel to the 1-2 lens group 17. The first shielding plate 15 may block a portion of the first light (e.g., a portion of the first light passing through the 1-1 lens group 13) and transmit the rest of the first light. The first shielding plate 15 may include a non-reflective coated plate. In an embodiment, the first shielding plate 15 may include a non-reflective coated stainless steel ("SUS") plate. Figure 2 The position and / or size of the described first area S1 may be controlled by the first shielding plate 15 .

[0072] The first light passing through the first shielding plate 15 and the 1-2 lens group 17 can pass through the first spatial filter 19. In an embodiment, as Figure 5AAs shown in FIG. 1 , the first spatial filter 19 may be a filter in which an annular (ring-shaped) aperture 19a is defined. The first light (ie, the first inspection light ISL1 (refer to FIG. 1 ) passing through the first spatial filter 19 Figure 1 )) can pass through the first beam splitter 41 (refer to Figure 1 ), travels toward the first lens group 43 and the second lens group 45, and passes through the third beam splitter 51 (refer to Figure 1 ).

[0073] As mentioned above Figure 2 As described above, the first inspection light ISL1 is irradiated to the first area S1 of the sample holder 71. Since the sample SP disposed on the sample holder 71 is linearly moved by the moving part 73, the image of the sample SP can be recorded in real time on the image sensor 100 of the camera 60 according to the movement of the sample SP (refer to Figure 3 ) (for example, Figure 3 In the first part 110).

[0074] The first inspection light ISL1 irradiated to the sample SP may be reflected by the sample SP. The light reflected by the sample SP may pass through the object portion 47 and the sensor-side optical filter 55, and be guided to the camera 60. In an embodiment, the light reflected by the sample SP may pass through the object portion 47, the third beam splitter 51, the third lens group 52, the fourth lens group 53, the image mirror 54, the sensor-side optical filter 55, and the image tube lens 56, and be guided to the camera 60.

[0075] The sensor-side optical filter 55 may have a structure different from that of the first spatial filter 19. Figure 5B As shown in , the sensor-side optical filter 55 may include a circular aperture 55a having an annular shape (ring shape) defined inside the light-blocking region. Figure 1 As shown in FIG. 1 , light passing through the sensor-side optical filter 55 (ie, light including information about the sample SP) travels toward the camera 60, and the image sensor 100 (refer to FIG. 1 ) of the camera 60 Figure 3 ) portion (e.g., the first portion 110) can generate a first image using the above-mentioned light.

[0076] In the case where a defective structure exists in the sample SP, reflection by the defective structure may be different from reflection by a normal structure. In the embodiment, light reflected by the defective structure may pass through the object portion 47 disposed on the most object side of the inspection device 1, the third beam splitter 51, the third lens group 52, the fourth lens group 53, the image mirror 54, the sensor side optical filter 55, and the image tube lens 56, and reach the image sensor 100 of the camera 60 (refer to Figure 3 ) part (for example, the first part 110 (refer to Figure 3)). In the first part 110 (refer to Figure 3 )In the first image generated by the image processing method, the defect may appear relatively bright and the surrounding environment of the defect may appear relatively dark.

[0077] Reference Figure 1 and Figure 4B , the second unit 20 may include a second shielding plate 25 disposed between the second light source 21 and the second spatial filter 29. The second light source 21 may emit a second light (e.g., white light). The second unit 20 may include a 2-1 lens group 23 between the second light source 21 and the second shielding plate 25, and a 2-2 lens group 27 between the second shielding plate 25 and the second spatial filter 29. In other words, the second unit 20 may include a 2-1 lens group 23, a second shielding plate 25, a 2-2 lens group 27, and a second spatial filter 29 disposed on a forward path of the second light emitted from the second light source 21. The second spatial filter 29 may be disposed between the second shielding plate 25 and the sample holder 71.

[0078] Each of the 2-1 lens group 23 and the 2-2 lens group 27 may include one or more lenses. The second light emitted from the second light source 21 may pass through the 2-1 lens group 23, pass through the second shielding plate 25 between the 2-1 lens group 23 and the 2-2 lens group 27, and proceed to the 2-2 lens group 27. The second shielding plate 25 may be disposed on an advancing path of the second light from the second light source 21 toward the sample holder 71, blocking a portion of the second light (e.g., a portion of the second light passing through the 2-1 lens group 23), and transmitting the remaining portion of the second light.

[0079] The area shielded by the second shielding plate 25 may be different from the area shielded by the first shielding plate 15. In the embodiment, although the first shielding plate 15 may shield one of the two side areas around the optical axis, for example, Figure 4A The right side area of ​​the optical axis in the embodiment of the present invention, but the second shielding plate 25 can shield one side area in the two side areas around the optical axis, for example, Figure 4B The area to the left of the optical axis. Figure 2 The position and / or size of the second area S2 described above can be controlled by the second shielding plate 25. Figure 1 As shown in FIG. 1 , the first inspection light ISL1 and the second inspection light ISL2 traveling toward the sample holder 71 on a line coaxial with the optical axes of the first lens group 43 and the second lens group 45 can be as shown in FIG. Figure 2 1 and 2. As shown in FIG. 1 , different areas are illuminated by the first shielding plate 15 of the first unit 10 and the second shielding plate 25 of the second unit 20. The second shielding plate 25 may be a non-reflection coated metal plate such as a non-reflection coated SUS plate.

[0080] The second light passing through the second shielding plate 25 and the 2-2 lens group 27 may pass through the second spatial filter 29. In an embodiment, the second spatial filter 29 may be defined as follows: Figure 5C The second light (i.e., the second inspection light ISL2) that has passed through the second spatial filter 29 can pass through the second beam splitter 42 and the first beam splitter 41 (refer to Figure 1 ) moves toward the first lens group 43 and the second lens group 45, and passes through the third beam splitter 51 (refer to Figure 1 ).

[0081] As mentioned above Figure 2 As described above, the second inspection light ISL2 is irradiated to the second area S2 of the sample holder 71. Since the sample SP disposed on the sample holder 71 is linearly moved by the moving part 73, the image of the sample SP can be recorded in real time on the image sensor 100 of the camera 60 according to the movement of the sample SP (refer to Figure 3 ) (for example, Figure 3 In the second part 120).

[0082] The second inspection light ISL2 irradiated to the sample SP may be reflected by the sample SP. The light reflected by the sample SP may pass through the third beam splitter 51 , the third lens group 52 , the fourth lens group 53 , and the image mirror 54 , and proceed toward the sensor-side optical filter 55 .

[0083] The light that has passed through the sensor-side optical filter 55 (ie, the light including the information about the sample SP) passes through the image tube lens 56 and is guided to the image tube lens 56. Figure 1 The camera 60 shown in FIG. 1 and the image sensor 100 of the camera 60 (see FIG. 1 ) Figure 3 ) (for example, Figure 3 The second part in the figure) can use the above light to generate a second image.

[0084] In the case where a defective structure exists in the sample SP, reflection by the defective structure different from reflection by a normal structure may occur. Even if the second light emitted from the second light source 21 is the same light (e.g., white light) as the first light emitted from the first light source 11, because the second light passes through the second spatial filter 29 different from the first spatial filter 19, the second inspection light ISL2 irradiated to the second area S2 may be irradiated at an incident angle different from that of the first inspection light ISL1.

[0085] Accordingly, even if the defects are the same, the image sensor 100 ( Figure 3 ) part (for example, the second part 120 ( Figure 3)) The second image generated may also be different from the first image. In the second image, the defect may appear relatively dark, and the surroundings of the defect may appear relatively bright.

[0086] Reference Figure 1 and Figure 4C , the third unit 30 may include a third shielding plate 35 disposed between the third light source 31 and the third spatial filter 39. The third light source 31 may emit a third light (e.g., white light). The third unit 30 may include a 3-1 lens group 33 between the third light source 31 and the third shielding plate 35, and a 3-2 lens group 37 between the third shielding plate 35 and the third spatial filter 39. In other words, the third unit 30 may include a 3-1 lens group 33, a third shielding plate 35, a 3-2 lens group 37, and a third spatial filter 39 disposed on a forward path of the third light emitted from the third light source 31. The third spatial filter 39 may be disposed between the third shielding plate 35 and the sample holder 71.

[0087] Each of the 3-1 lens group 33 and the 3-2 lens group 37 may include one or more lenses. The third light emitted from the third light source 31 may pass through the 3-1 lens group 33, pass through the third shielding plate 35 between the 3-1 lens group 33 and the 3-2 lens group 37, and proceed to the 3-2 lens group 37. The third shielding plate 35 may be disposed on an advancing path of the third light from the third light source 31 toward the sample holder 71, blocks a portion of the third light (e.g., a portion of the third light passing through the 3-1 lens group 33), and transmits the rest of the third light.

[0088] The area shielded by the third shielding plate 35 may be different from the area shielded by the second shielding plate 25. In an embodiment, the third shielding plate 35 may transmit the area through which the optical axis passes and shield its surrounding environment. Figure 2 The position and / or size of the third area S3 described above can be controlled by the third shielding plate 35. Figure 1 As shown in FIG. 1 , the first inspection light ISL1, the second inspection light ISL2, and the third inspection light ISL3 traveling toward the sample holder 71 on a line coaxial with the optical axes of the first lens group 43 and the second lens group 45 can be as shown in FIG. Figure 2 The first to third shielding plates 15, 25 and 35 provided to the first to third units 10, 20 and 30, respectively, are shown to irradiate different areas. The third shielding plate 35 may be a non-reflection coated metal plate such as a non-reflection coated SUS plate.

[0089] The third light passing through the third shielding plate 35 and the 3-2 lens group 37 may pass through the third spatial filter 39. In an embodiment, the third spatial filter 39 may be defined as follows: Figure 5DThe aperture 39a of the third spatial filter 39 may be biased to one side. In an embodiment, the third light (ie, the third inspection light ISL3) passing through the third spatial filter 39 may pass through the second beam splitter 42 and the first beam splitter 41 (see Figure 1 ) and travels toward the first lens group 43 and the second lens group 45, and passes through the third beam splitter 51 (refer to Figure 1 ).

[0090] As mentioned above Figure 2 As described above, the third inspection light ISL3 is irradiated to the third area S3 of the sample holder 71. Since the sample SP disposed on the sample holder 71 is linearly moved by the moving part 73, the image of the sample SP can be recorded in real time on the image sensor 100 of the camera 60 according to the movement of the sample SP (refer to Figure 3 ) (for example, Figure 3 In the third part 130).

[0091] The third inspection light ISL3 irradiated to the sample SP may be reflected according to the structure of the sample SP. The light reflected by the sample SP may pass through the object portion 47 and the sensor side optical filter 55, and be guided to the camera 60. In an embodiment, the light reflected by the sample SP may pass through the object portion 47, the third beam splitter 51, the third lens group 52, the fourth lens group 53, the image mirror 54, the sensor side optical filter 55, and the image tube lens 56, and be guided to the camera 60.

[0092] The light passing through the sensor-side optical filter 55 (i.e., the light including the information about the sample SP) is directed toward Figure 1 The camera 60 shown in FIG. 1 is traveling, and the image sensor 100 (refer to FIG. 10A ) of the camera 60 is traveling. Figure 3 ) (for example, Figure 3 The third portion 130) in the image may generate a third image using the light.

[0093] In the case where a defective structure exists in the sample SP, reflection by the defective structure may occur, which is different from reflection by a normal structure. Even if the third light emitted from the third light source 31 is the same light (for example, white light) as the first light and the second light emitted from the first light source 11 and the second light source 21, respectively, because the third light passes through the third spatial filter 39, the third inspection light ISL3 (refer to Figure 1 ) may be irradiated at an incident angle different from the incident angles of the first inspection light ISL1 and the second inspection light ISL2. Figure 1 ) can be irradiated in a direction inclined relative to the upper surface of the sample holder 71.

[0094] Use the third inspection light ISL3 (refer to Figure 1 ) generated by the image sensor 100 (see Figure 3 ) of the third part 130 (refer to Figure 3 ) The third image generated may be different from the first image and the second image. In an embodiment, in the third image, the defect may appear relatively three-dimensional.

[0095] Figure 6 This is a conceptual diagram for explaining the generation of a TDI image by an image sensor of a camera of a defect inspection device.

[0096] Reference Figure 6 , the first portion 110 of the image sensor 100 may include a plurality of pixel lines C11, C12, C13, . . . , C1n, where n is a natural number greater than 0. Each of the pixel lines C11, C12, C13, . . . , C1n may be a stage for TDI.

[0097] As the sample SP moves linearly, each of the pixel lines C11, C12, C13, ..., C1n may obtain a signal of an image of the sample SP at a different time. In an embodiment, a signal of a first portion SP1 of the sample SP received by the first pixel line C11 at a first time point, a signal of a first portion SP1 of the sample SP received by the second pixel line C12 at a second time point, ..., a signal of a first portion SP1 of the sample SP received by the nth pixel line C1n at an nth time point may be accumulated to generate an image of the first portion SP1 of the sample SP. A first image of the entire sample SP may be generated using this method.

[0098] Like the first part 110 generating the first image using TDI, the second part 120 may generate the second image using TDI, and the third part 130 may generate the third image using TDI.

[0099] exist Figure 6 1 and 2 are shown as the first to third parts 110, 120 and 130 being spaced apart from each other and being spaced apart from each other in the linear moving direction of the sample SP. In another embodiment, the first to third parts 110, 120 and 130 are spaced apart from each other and may be spaced apart from each other in a direction intersecting the linear moving direction of the sample SP (e.g., Figure 6 The two components are arranged side by side in the longitudinal direction (in the longitudinal direction), but the present disclosure is not limited to this.

[0100] In another embodiment, the first to third portions 110, 120, and 130 are shown to be spaced apart from each other and spaced apart from each other in a direction intersecting the linear moving direction of the sample SP. In an embodiment, the first to third portions 110, 120, and 130 may be spaced apart from each other in a direction intersecting the linear moving direction of the sample SP (e.g., Figure 6 In this case, each stage for the camera 60 to perform TDI may include a portion of the first portion 110, a portion of the second portion 120, and a portion of the third portion 130.

[0101] In the comparative example, in the case of a relatively low-resolution defect inspection apparatus using an area camera, the distance between the camera and the sample (hereinafter, also referred to as a working distance) can be sufficiently ensured, but as in a display that provides a relatively high-resolution image, a relatively high-resolution camera is desired to inspect a sample SP whose structure is quite fine. In this case, the above-mentioned working distance is reduced, and because the working distance is reduced, it is difficult to ensure a space for irradiating the first to third inspection lights traveling toward the sample at different incident angles.

[0102] However, in reference Figures 1 to 6 In the described embodiment, because the inspection lights under different conditions (i.e., the first to third inspection lights ISL1, ISL2 and ISL3) travel on a path coaxial with the first lens group 43 and the second lens group 45, and the light reflected by the sample SP travels on a path coaxial with the third lens group 52 and the fourth lens group 53 and is received by the camera 60, a sufficient working distance between the sample SP and the camera 60 can be ensured.

[0103] In an embodiment, because the first to third units 10, 20 and 30 respectively include first to third shielding plates 15, 25 and 35, the first to third inspection lights ISL1, ISL2 and ISL3 traveling toward the sample holder 71 on a path coaxial with the first lens group 43 and the second lens group 45 can simultaneously irradiate different areas.

[0104] In an embodiment, a single image sensor 100 is divided into Figure 3 The multiple parts described (e.g., the first to third parts 110, 120, and 130) are irradiated with inspection lights of different conditions (i.e., the first to third inspection lights ISL1, ISL2, and ISL3) for each part. Accordingly, multiple images of the sample SP can be obtained in a single scan. Therefore, with only one scan, defects of the sample SP can be quickly and accurately inspected.

[0105] In the embodiment, since the single image sensor 100 is divided and the plurality of parts generate images, the detector 80 easily matches or extracts the coordinates of the defective position during defect inspection. Therefore, defects of the sample SP can be inspected at a relatively high speed.

[0106] In the embodiment, a device can be provided in which a working distance can be sufficiently ensured, a relatively high-resolution image can be generated with only one scan of a sample, and defects can be detected at a relatively high speed. However, this effect is an example, and the present disclosure is not limited to this effect.

[0107] It should be understood that the embodiments described herein should be considered in a descriptive sense only and not for limiting purposes. The description of features or advantages within each embodiment should generally be considered applicable to other similar features or advantages in other embodiments. Although the embodiments have been described with reference to the drawings, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope as defined by the claims.

Claims

1. A defect inspection device, comprising: A first unit irradiates a first inspection light toward a sample holder; a second unit, irradiating a second inspection light toward the sample holder; a third unit, irradiating a third inspection light toward the sample holder; a camera comprising a single image sensor generating an image of a sample by time-delay integration, the sample being disposed on the sample holder and moving linearly, the single image sensor comprising: a first portion generating a first image of the sample captured by the first inspection light; a second portion generating a second image of the sample captured by the second inspection light; and a third portion generating a third image of the sample captured by the third inspection light; and a detector that detects defects of the sample based on the first image, the second image, and the third image provided by the camera, The first inspection light, the second inspection light and the third inspection light are irradiated toward the sample holder at the same time.

2. The defect inspection device according to claim 1, wherein: The first unit comprises: A first light source, emitting a first light; a first shielding plate disposed on an advancing path of the first light from the first light source toward the sample holder and blocking a portion of the first light; and a first spatial filter, arranged on the advancing path of the first light and between the first shielding plate and the sample holder; Wherein, the second unit comprises: a second light source, emitting a second light; a second shielding plate disposed on an advancing path of the second light from the second light source toward the sample holder and blocking a portion of the second light; and a second spatial filter disposed on the advancing path of the second light and between the second shielding plate and the sample holder, and Wherein, the third unit comprises: a third light source, emitting a third light; a third shielding plate disposed on an advancing path of the third light from the third light source toward the sample holder and blocking a portion of the third light; and A third spatial filter is arranged on the advancing path of the third light and between the third shielding plate and the sample holder.

3. The defect inspection device according to claim 2, wherein: An irradiation area of ​​the first inspection light, an irradiation area of ​​the second inspection light, and an irradiation area of ​​the third inspection light are different from each other by the first shielding plate, the second shielding plate, and the third shielding plate, respectively.

4. The defect inspection device according to claim 3, wherein: The irradiation area of ​​the first inspection light, the irradiation area of ​​the second inspection light, and the irradiation area of ​​the third inspection light do not overlap with each other on the sample holder.

5. The defect inspection device according to claim 2, wherein: Each of the first shielding plate, the second shielding plate, and the third shielding plate includes a non-reflective coating plate.

6. The defect inspection device according to claim 2, wherein: The first spatial filter, the second spatial filter, and the third spatial filter respectively include apertures of different shapes.

7. The defect inspection device according to claim 1, further comprising: at least one lens group, arranged between the first unit to the third unit and the sample holder, Wherein, each of the first inspection light, the second inspection light, and the third inspection light passes through the at least one lens group and is irradiated toward the sample holder.

8. The defect inspection device according to claim 7, further comprising: A sensor-side optical filter, through which light among the first inspection light reflected from the surface of the sample, light among the second inspection light reflected from the surface of the sample, and light among the third inspection light reflected from the surface of the sample pass, wherein the sensor-side optical filter is adjacent to the camera.

9. The defect inspection device according to claim 8, wherein: The light reflected from the surface of the sample among the first inspection light, the light reflected from the surface of the sample among the second inspection light, and the light reflected from the surface of the sample among the third inspection light are bent by a beam splitter to advance toward the sensor-side optical filter.

10. The defect inspection device according to claim 1, wherein: The camera generates the first image of the sample based on the signal obtained from the first portion, generates the second image of the sample based on the signal obtained from the second portion, and generates the third image of the sample based on the signal obtained from the third portion.

11. The defect inspection device according to claim 10, wherein: When a defect is included in the sample, an image of the defect included in the first image, an image of the defect included in the second image, and an image of the defect included in the third image are different from each other.

12. The defect inspection device according to claim 11, wherein: The first image includes an image in which the defect appears relatively bright and the surroundings of the defect appear relatively dark, the second image includes an image in which the defect appears relatively dark and the surroundings of the defect appear relatively bright, and the third image includes an image in which the defect appears relatively three-dimensional.

13. The defect inspection device according to claim 11, wherein: The detector detects a position of the defect based on the first image, the second image, and the third image.

14. The defect inspection device according to any one of claims 1 to 13, wherein: The single image sensor further includes a dummy portion disposed between two adjacent portions among the first portion, the second portion, and the third portion.

Images