KR20240133899A - Inspection device and method of inspection using the same - Google Patents

Abstract

The present invention includes a light source that emits light, an aberration separation lens that is disposed on an inspection object including a plurality of layers and generates chromatic aberration in light emitted from the light source to provide a plurality of transmitted lights having different wavelengths to the inspection object, a plurality of color filters that separate the reflected light that is incident when the plurality of transmitted lights are reflected from the inspection object by wavelength and output a plurality of color lights, and a detection unit that receives the plurality of color lights from the plurality of color filters and generates an image of the inspection object. The detection unit includes a plurality of areas respectively corresponding to the plurality of color filters and a receiving unit that receives the plurality of color lights through the plurality of areas, and a generating unit that generates a plurality of images for each of the plurality of layers of the inspection object using the plurality of color lights.

Description

{INSPECTION DEVICE AND METHOD OF INSPECTION USING THE SAME}

The present invention relates to an inspection device with improved reliability and an inspection method using the same.

Various inspection devices can be used to inspect objects with multilayer structures. Among them, optical inspection devices can inspect objects using cameras and microscopes. For example, optical inspection devices can inspect for short defects, open defects, or the presence of fine particles in the range of several ㎛ to several tens ㎛. In addition, optical inspection devices can inspect for foreign substances or residual films in the range of several hundred ㎛ or more.

The purpose of the present invention is to provide an inspection device with improved accuracy and reliability.

The purpose of the present invention is to provide an inspection method using an inspection device with improved accuracy and reliability.

According to one embodiment of the present invention, an inspection device includes: a light source that emits light; an aberration separation lens that is arranged on an inspection object including a plurality of layers and generates chromatic aberration in the light emitted from the light source to provide a plurality of transmitted lights having different wavelengths to the inspection object; a plurality of color filters that separate incident reflected light, which is reflected from the plurality of transmitted lights by wavelength, and output a plurality of color lights; and a detection unit that receives the plurality of color lights from the plurality of color filters and generates an image of the inspection object, wherein the detection unit includes a plurality of regions respectively corresponding to the plurality of color filters and receives the plurality of color lights through the plurality of regions; and a generation unit that generates a plurality of images for each of the plurality of layers of the inspection object using the plurality of color lights.

An inspection device wherein the plurality of color lights include first color lights, second color lights, and third color lights having different wavelengths.

The plurality of color filters may include a first color filter that transmits the first color light; a second color filter that transmits the second color light; and a third color filter that transmits the third color light.

The above plurality of regions may include a first region corresponding to the first color filter; a second region corresponding to the second color filter; and a third region corresponding to the third color filter.

Each of the first to third regions may extend in a first direction, and the first to third regions may be arranged along a second direction that is perpendicular to the first direction.

The sizes of each of the first to third regions may be different from each other.

The first color light may be blue light, the second color light may be green light, and the third color light may be red light.

Each of the first color light, the second color light, and the third color light may correspond to an image of each of the plurality of layers of the inspection target.

The above plurality of transmitted lights include first transmitted lights, second transmitted lights, and third transmitted lights having different wavelengths, and the focal lengths of each of the first transmitted lights, the second transmitted lights, and the third transmitted lights may be different from each other.

The wavelength of the third transmitted light may be longer than the wavelength of the second transmitted light, and the wavelength of the second transmitted light may be longer than the wavelength of the first transmitted light.

The focal length of the third transmitted light may be longer than the focal length of the second transmitted light, and the focal length of the second transmitted light may be longer than the focal length of the first transmitted light.

An inspection device according to one embodiment of the present invention may further include a splitter that changes the path of light emitted from the light source.

The above receiver may be an optical image sensor that detects light.

An inspection method according to one embodiment of the present invention includes the steps of: providing light output from a light source to an aberration separation lens; providing a plurality of transmitted lights having different wavelengths through the aberration separation lens to an inspection target including a plurality of layers; providing reflected light reflected from each of the plurality of layers by each of the plurality of transmitted lights to a plurality of color filters; outputting a plurality of color lights having different wavelengths from the plurality of color filters; providing the plurality of color lights to a detection unit; and generating a plurality of images for each of the plurality of layers of the inspection target using the plurality of color lights through the detection unit.

The above detection unit may include a receiving unit including a plurality of areas each corresponding to the plurality of color filters, and a generating unit generating images of the plurality of layers of the inspection target.

The inspection method according to one embodiment of the present invention may further include, prior to the step of generating the plurality of layer-by-layer images, the step of each of the plurality of areas receiving a plurality of color lights separated by wavelength.

The step of irradiating light from the light source to the aberration separation lens may further include the step of changing the path of the light irradiated from the light source through a splitter so that the light is directed to the aberration separation lens.

The inspection device of the present invention can easily obtain a layer-by-layer image of an inspection object by using a plurality of color lights having layer-by-layer image information transmitted through a plurality of color filters and a plurality of aberration separation lenses that generate a plurality of transmitted lights having different wavelengths. Accordingly, the inspection process is simplified and the inspection time can be shortened.

FIG. 1 is a drawing showing an inspection device according to one embodiment of the present invention.
Figure 2 is an enlarged view of the AA area shown in Figure 1.
FIG. 3 is a cross-sectional view illustrating a detection unit and a color filter according to one embodiment of the present invention.
FIG. 4a is a perspective view of a receiver according to one embodiment of the present invention.
FIG. 4b is a drawing schematically illustrating a plane image of each layer of the inspection target corresponding to the first to third areas illustrated in FIG. 4a.
FIG. 5 is a block diagram showing an inspection method according to one embodiment of the present invention.

The present invention can be modified in various ways and can take various forms, and specific embodiments are illustrated in the drawings and described in detail in the text. However, this is not intended to limit the present invention to specific disclosed forms, but should be understood to include all modifications, equivalents, or substitutes included in the spirit and technical scope of the present invention.

In this specification, when a component (or region, layer, portion, etc.) is referred to as being “on,” “connected to,” or “coupled to” another component, it means that it can be directly disposed/connected/coupled to the other component, or that a third component may be disposed between them.

Identical drawing symbols refer to identical components. Also, in the drawings, the thicknesses, proportions, and dimensions of the components are exaggerated for the purpose of effectively explaining the technical contents.

“And/or” includes any combination of one or more of the associated constructs that can be defined.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are only used to distinguish one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. The singular expression includes the plural expression unless the context clearly indicates otherwise.

Additionally, terms such as "below," "lower," "above," and "upper," are used to describe the relationships between components depicted in the drawings. These terms are relative concepts and are described based on the directions indicated in the drawings.

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. In addition, terms that are defined in commonly used dictionaries, such as terms, should be interpreted as having a meaning consistent with the meaning in the context of the relevant art, and are explicitly defined herein, unless interpreted in an idealized or overly formal sense.

It should be understood that the terms "include" or "have" are intended to specify the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not exclude in advance the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

Fig. 1 is a drawing showing an inspection device according to one embodiment of the present invention. Fig. 2 is an enlarged view of the AA area shown in Fig. 1.

Referring to FIG. 1, the inspection device (1000) may include a light source (LA), an aberration separation lens (ASL), a detection unit (100), and a color filter (CF).

Referring to Figure 1, a light source (LA) can emit light (Lg). The light (Lg) can be light in which light rays having multiple wavelengths are mixed. For example, the light (Lg) can be light in which multiple wavelengths are mixed, such as white light. Light in which light of a desired wavelength is selectively mixed can be emitted.

Light (Lg) can be provided by an aberration separation lens (ASL). A splitter (SPL) can be arranged on the path of light (Lg). The splitter (SPL) transmits or reflects light (Lg) emitted from a light source (LA) and can be configured as a general beam splitter. The splitter (SPL) is positioned in the direction of propagation of light (Lg) emitted from the light source (LA) and can reflect the light (Lg) toward one side of the splitter (SPL). Specifically, the splitter (SPL) can change the path of light (Lg) so that the light (Lg) faces the aberration separation lens (ASL). In addition, the splitter (SPL) can transmit reflected light (RLg) reflected from an inspection target (200) to be described later toward the other side of the splitter (SPL). Hereinafter, unless otherwise stated, one direction is the direction opposite to the third direction (DR3) toward the inspection subject (200), and the other direction is the direction opposite to the inspection subject (200) and corresponds to the third direction (DR3).

Although not shown, a condenser lens may be placed between the light source (LA) and the splitter (SPL). The condenser lens may condense light transmitted to the splitter (SPL). For example, the condenser lens may be a convex lens.

The light (Lg) whose path has been changed by the splitter (SPL) may be incident on the aberration separation lens (ASL) placed on the inspection target (200). The aberration separation lens (ASL) is a lens that generates chromatic aberration, and may be a lens that is intentionally set to generate axial chromatic aberration in order to create a layer-by-layer image according to the height of the inspection target (200). Chromatic aberration occurs due to the difference in diffraction index according to the wavelength when the light (Lg) passes through the aberration separation lens (ASL). Due to the difference in the refractive index of light, not all wavelengths are precisely focused on one focus, and thus the focus is formed at different locations for each wavelength. For example, the spectrum of visible light has various wavelengths of light ranging from red to violet, and the refractive index of light is also configured differently according to the various wavelengths of light. In this way, when light passing through an aberration separation lens (ASL) is focused differently at different locations according to wavelength, image information for each layer according to the depth of the inspection target (200) can be obtained according to the wavelength of the reflected light.

Referring to FIG. 2 together, the aberration separation lens (ASL) may include a first lens (ASL1) and a second lens (ASL2). The first lens (ASL1) may be a diffractive lens that significantly generates chromatic aberration. For example, the first lens (ASL1) may be a spherical lens or a GRIN lens (Gradient-Index Lens). A spherical lens is a lens with a constant radius of curvature, so that only light rays very close to the optical axis are focused at a point, and light rays passing through the edge of the lens are not focused at a point, thereby causing aberration. A GRIN lens may have aberration because the distance from the plane position and the cross section to the focus periodically changes with respect to the length of the lens. The second lens (ASL2) may be a lens that reduces chromatic aberration. For example, the second lens (ASL2) may be a concave lens. The second lens (ASL2) can correct chromatic aberration formed in the first lens (ASL1) and reduce chromatic aberration caused by the first lens (ASL1) in the area overlapping with the second lens (ASL2).

As the first lens (ASL1) and the second lens (ASL2) overlap on a plane, a first aberration region (AB1), a second aberration region (AB2), and a third aberration region (AB3) can be defined. Specifically, the region overlapping the first lens (ASL1) and the second lens (ASL2) can be defined as the first aberration region (AB1), and the region not overlapping the first lens (ASL1) and the second lens (ASL2) can be defined as the second aberration region (AB2), and the third aberration region (AB3). Accordingly, as the area of the first lens (ASL1) increases, the size of the first aberration region (AB1) increases, and as the size of the first lens (ASL1) decreases, the size of the first aberration region (AB1) decreases. Unlike as illustrated, the positions of the second aberration region (AB2) and the third aberration region (AB3) may be changed relative to each other. The sizes of the second aberration region (AB2) and the third aberration region (AB3) may be the same, and the size of the first aberration region (AB1) may be larger than the sizes of the second aberration region (AB2) and the third aberration region (AB3). However, the present invention is not limited thereto, and the sizes of the first aberration region (AB1), the second aberration region (AB2), and the third aberration region (AB3) may be different from each other.

The first aberration region (AB1) may be a region having less chromatic aberration than the second aberration region (AB2) and the third aberration region (AB3). Specifically, the first aberration region (AB1) may be a region in which chromatic aberration is reduced by the second lens (ASL2). The second aberration region (AB2) and the third aberration region (AB3) may be regions that do not overlap with the second lens (ASL2) and may be regions having large chromatic aberration. The second aberration region (AB2) and the third aberration region (AB3) may have the same chromatic aberration. However, the present invention is not limited thereto, and the second aberration region (AB2) and the third aberration region (AB3) may have different chromatic aberrations.

Light passing through the aberration separation lens (ASL) can be defined as a plurality of transmitted lights (TLg) having different wavelengths. The plurality of transmitted lights (TLg) can include a first transmitted light (TLg1), a second transmitted light (TLg2), and a third transmitted light (TLg3) having different wavelengths. The first transmitted light (TLg1) can be generated from the first aberration region (AB1), the second transmitted light (TLg2) can be generated from the second aberration region (AB2), and the third transmitted light (TLg3) can be generated from the third aberration region (AB3).

The wavelengths of the first transmitted light (TLg1), the second transmitted light (TLg2), and the third transmitted light (TLg3) may be different from each other. As described above, the focal length may vary depending on the wavelength. Specifically, the longer the wavelength, the longer the focal length may be formed. According to one embodiment of the present invention, the wavelength of the third transmitted light (TLg3) may be longer than the wavelength of the second transmitted light (TLg2), and the wavelength of the second transmitted light (TLg2) may be longer than the wavelength of the first transmitted light (TLg1). Accordingly, the focal length of the third transmitted light (TLg3) may be longer than the focal length of the second transmitted light (TLg2), and the focal length of the second transmitted light (TLg2) may be longer than the focal length of the first transmitted light (TLg1).

The inspection target (200) may include a first layer (L1), a second layer (L2), and a third layer (L3). Since the focal lengths of the first to third transmitted lights (TLg1, TLg2, TLg3) become longer in the order of the first transmitted light (TLg1) to the third transmitted light (TLg3), the first transmitted light (TLg1) may be focused on the upper surface of the first layer (L1) and reflected from the upper surface of the first layer (L1), the second transmitted light (TLg2) may be focused on the upper surface of the second layer (L2) and reflected from the upper surface of the second layer (L2), and the third transmitted light (TLg3) may be focused on the upper surface of the third layer (L3) and reflected from the upper surface of the third layer (L3).

Referring back to FIG. 1, a plurality of transmitted lights (TLg, see FIG. 2) are reflected from each layer of the inspection target (200), and the generated reflected light (RLg) can be transmitted toward the other side of the splitter (SPL). The reflected light (RLg) transmitted through the splitter (SPL) can pass through the refracting lens (RLS). The reflected light (RLg) transmitted through the refracting lens (RLS) can be refracted and incident on the detection unit (100). The refracting lens (RLS) can be a condensing lens that refracts the reflected light (RLg).

The reflected light (RLg) may be incident on a color filter (CF) arranged on a detection unit (100). The color filter (CF) may separate the reflected light (RLg) by wavelength and output multiple color lights. The detection unit (100) may include a receiving unit (110) that receives multiple color lights (CLg), and a generating unit (120) that generates a layer-by-layer image of an inspection target (200) using the multiple color lights (CLg). The process of the detection unit (100) generating a layer-by-layer image of an inspection target (200) using the multiple color lights (CLg) will be described in detail in FIG. 3.

Fig. 3 is a cross-sectional view illustrating a detection unit and a color filter according to one embodiment of the present invention. In Fig. 3, the color filter (CF) and the receiving unit (110) are illustrated to be spaced apart from each other in order to display a plurality of color lights (CLg).

Referring to FIG. 3, a plurality of color filters (CF) may be provided. The color filter (CF) may include a first color filter (CF1), a second color filter (CF2), and a third color filter (CF3). The first color filter (CF1), the second color filter (CF2), and the third color filter (CF3) may transmit light of different wavelengths among the reflected light (RLg). According to one embodiment of the present invention, the first color filter (CF1) may transmit blue light among the reflected light (RLg), the second color filter (CF2) may transmit green light among the reflected light (RLg), and the third color filter (CF3) may transmit red light among the reflected light (RLg). The number of color filters (CF) is not limited to that illustrated, and the color filter (CF) may include four or more color filters that transmit different colors.

A plurality of color lights (CLg) passing through the color filter (CF) may have different wavelengths. Specifically, the plurality of color lights (CLg) may include a first color light (CLg1), a second color light (CLg2), and a third color light (CLg3). The first color light (CLg1) may be light passing through the first color filter (CF1), the second color light (CLg2) may be light passing through the second color filter (CF2), and the third color light (CLg3) may be light passing through the third color filter (CF3).

The wavelengths of the first color light (CLg1), the second color light (CLg2), and the third color light (CLg3) may be different from each other. The wavelength of the third color light (CLg3) is longer than the wavelength of the second color light (CLg2), and the wavelength of the second color light (CLg2) is longer than the wavelength of the first color light (CLg1). According to one embodiment of the present invention, the first color light (CLg1) may be blue light, the second color light (CLg2) may be green light, and the third color light (CLg3) may be red light. However, the colors of each of the first color light (CLg1), the second color light (CLg2), and the third color light (CLg3) are not limited thereto. Each of the first color light (CLg1), the second color light (CLg2), and the third color light (CLg3) may include information about an image of a different layer of the inspection target (200, see FIG. 1). Specifically, the first color light (CLg1) may include image information corresponding to the upper surface of the first layer (L1, see FIG. 2), the second color light (CLg2) may include image information corresponding to the upper surface of the second layer (L2, see FIG. 2), and the third color light (CLg3) may include image information corresponding to the upper surface of the third layer (L3, see FIG. 2).

The receiving unit (110) may include a plurality of areas. Specifically, the receiving unit (110) may include a first area (A1), a second area (A2), and a third area (A3). Each of the first area (A1), the second area (A2), and the third area (A3) may correspond to and overlap a first color filter (CF1), a second color filter (CF2), and a third color filter (CF3), respectively. As illustrated, the sizes of the second area (A2) and the third area (A3) may be the same, and the size of the first area (A1) may be larger than the sizes of the second area (A2) and the third area (A3), respectively. However, the present invention is not limited thereto, and the sizes of the first area (A1), the second area (A2), and the third area (A3) may be different from each other, and the relationship between the sizes of the first area (A1), the second area (A2), and the third area (A3) may be different from each other.

The receiving unit (110) can receive a first color light (CLg1) transmitted through a first color filter (CF1), a second color light (CLg2) transmitted through a second color filter (CF2), and a third color light (CLg3) transmitted through a third color filter (CF3). Specifically, the first region (A1) can receive the first color light (CLg1), the second region (A2) can receive the second color light (CLg2), and the third region (A3) can receive the third color light (CLg3). The receiving unit (110) can obtain image information about a portion on the upper surface of the first layer (L1, see FIG. 2) where the first transmitted light (TLg1, see FIG. 2) is focused through the first color light (CLg1) received in the first area (A1), can obtain image information about a portion on the upper surface of the second layer (L2, see FIG. 2) where the second transmitted light (TLg2, see FIG. 2) is focused through the second color light (CLg2) received in the second area (A2), and can obtain image information about a portion on the upper surface of the third layer (L3, see FIG. 2) where the third transmitted light (TLg3, see FIG. 2) is focused through the third color light (CLg3) received in the third area (A3). According to one embodiment of the present invention, the receiving unit (110) may correspond to a light sensor that detects light. For example, the receiver (110) may be an optical image sensor that detects a first color light (CLg1), a second color light (CLg2), and a third color light (CLg3) and extracts image information corresponding to the first color light (CLg1), the second color light (CLg2), and the third color light (CLg3).

The generation unit (120) can generate a layer-by-layer image of the inspection target (200, see FIG. 1) through image information corresponding to the first color light (CLg1), the second color light (CLg2), and the third color light (CLg3) acquired by the reception unit (110). For example, the generation unit (120) can generate a layer-by-layer image of the inspection target (200) by extracting and combining image information corresponding to the first color light (CLg1), the second color light (CLg2), and the third color light (CLg3).

Referring to FIGS. 1 to 3, an inspection device (1000) according to one embodiment of the present invention can obtain images of each layer of an inspection target (200) through inspection using an aberration separation lens (ASL) and a plurality of color filters (CF). Accordingly, the inspection process is simplified and the inspection time can be shortened compared to a case where images of a plurality of layers (L1, L2, L3) of an inspection target (200) are respectively obtained through a plurality of cameras.

Fig. 4a is a perspective view of a receiver according to one embodiment of the present invention. Fig. 4b is a drawing briefly illustrating a plane image of each layer of an inspection target corresponding to the first to third regions illustrated in Fig. 4a.

Referring to FIG. 4A, the receiving unit (110) may include a plurality of unit pixels (PX) arranged in a first direction (DR1) and a second direction (DR2). Each of the plurality of unit pixels (PX) may receive at least one of the first color light (CLg1), the second color light (CLg2), and the third color light (CLg3) illustrated in FIG. 3. As each of the plurality of unit pixels (PX) receives at least one of the first color light (CLg1), the second color light (CLg2), and the third color light (CLg3), the receiving unit (110) may obtain information on each layer of the inspection target (200, see FIG. 1) in units of the plurality of unit pixels (PX).

The receiving unit (110) may include a first region (A1), a second region (A2), and a third region (A3). Each of the first region (A1), the second region (A2), and the third region (A3) may include a plurality of unit pixels (PX). According to one embodiment of the present invention, each of the first region (A1), the second region (A2), and the third region (A3) may extend in the first direction (DR1) and be arranged along the second direction (DR2). As illustrated, the receiving unit (110) includes three regions, but is not limited thereto and may include four or more regions.

Referring to FIGS. 2 and 4A together, the first region (A1), the second region (A2), and the third region (A3) may each correspond to the first aberration region (AB1), the second aberration region (AB2), and the third aberration region (AB3). Specifically, the first region (A1), the second region (A2), and the third region (A3) may each extract information corresponding to a plurality of layer-by-layer images of the inspection target (200). That is, the receiving unit (110) may obtain image information regarding a portion where a plurality of unit pixels (PX) included in the first region (A1) receive the first color light (CLg1), and the first transmitted light (TLg1) is focused on the upper surface of the first layer (L1) through the first color light (CLg1). In addition, the receiving unit (110) can obtain image information about a portion where the second transmitted light (TLg2) is focused on the upper surface of the second layer (L2) through the second color light (CLg2) received by the plurality of unit pixels (PX) included in the second area (A2). In addition, the receiving unit (110) can obtain image information about a portion where the third transmitted light (TLg3) is focused on the upper surface of the third layer (L3) through the third color light (CLg3) received by the plurality of unit pixels (PX) included in the third area (A3). Accordingly, the generating unit (120) can obtain partial images of each layer of the inspection target (200) as a single image.

Referring to FIG. 4b together, the image (IMG) generated by the generation unit (120, see FIG. 3) may include a first image (IM1), a second image (IM2), and a third image (IM3). The generation unit (120) may analyze image information of color lights (CLg1, CLg2, CLg3, see FIG. 3) of different wavelengths received from the reception unit (110, see FIG. 4a) to generate the first image (IM1), the second image (IM2), and the third image (IM3).

The first image (IM1) may be an image generated from the first color light (CLg1) transmitted from the first area (A1), the second image (IM2) may be an image generated from the second color light (CLg2) transmitted from the second area (A2), and the third image (IM3) may be an image generated from the third color light (CLg3) transmitted from the third area (A3). Referring to FIGS. 1 and 2 together, when the light (Lg) is irradiated from the light source (LA) to inspect the inspection target (200), the receiving unit (110) may extract information corresponding to images of each of the plurality of layers (L1, L2, L3) of the inspection target (200) on which the transmitted light (TLg) from the first to third areas (A1, A2, A3) is focused. However, when the inspection target (200) is moved in the first direction (DR1) or the second direction (DR2) or the inspection device (1000) is moved in the first direction (DR1) or the second direction (DR2) and the inspection is performed by continuously irradiating the inspection target (200) with light (Lg), information on the entire images of each of the multiple layers (L1, L2, L3) of the inspection target (200) can be extracted. Accordingly, the entire images of each layer (L1, L2, L3) can be acquired as the first image (IM1), the second image (IM2), and the third image (IM3) as illustrated in FIG. 4b. That is, the first image (IM1) can be an entire image of the upper surface of the first layer (L1), the second image (IM2) can be an entire image of the upper surface of the second layer (L2), and the third image (IM3) can be an entire image of the upper surface of the third layer (L3).

Referring to FIG. 2 and FIG. 4b, the present invention is not limited to acquiring images of the upper surfaces of each of the first layer (L1), the second layer (L2), and the third layer (L3), and can acquire a three-dimensional image of the inspection subject (200). For example, a three-dimensional image of the inspection subject (200) can be generated by further including a process of collating layer-by-layer images (IM1, IM2, IM3) of the inspection subject (200) together with depth information according to the wavelengths of the first to third color lights (CLg1, CLg2, CLg3, see FIG. 3).

FIG. 5 is a block diagram showing an inspection method according to one embodiment of the present invention.

The inspection method according to one embodiment of the present invention described below corresponds to an inspection method using the inspection device (1000, see FIG. 1) described above. However, it is not limited to the inspection device (1000) described above, and can be applied to other inspection devices that perform substantially the same function. For the convenience of explanation, the description of the inspection target (200) and the inspection device (1000) described below will be described together with reference to FIGS. 1 to 4b.

Referring to FIG. 5, an inspection method according to an embodiment of the present invention may include a step (S100) of providing light output from a light source to an aberration separation lens, a step (S200) of providing a plurality of transmitted lights to an inspection target including a plurality of layers, a step (S300) of providing reflected light reflected from each of the plurality of transmitted lights to a plurality of color filters, a step (S400) of outputting a plurality of color lights having different wavelengths from the plurality of color filters, a step (S500) of providing a plurality of color lights separated by wavelength from the plurality of color filters to a detection unit, and a step (S600) of generating an image of each layer of the inspection target.

Referring to FIGS. 1 and 5, light (Lg) may be emitted from a light source (LA) and provided to an aberration separation lens (ASL). The step (S100) of providing light output from the light source to the aberration separation lens may further include a step of changing the propagation path of the light (Lg) so that the light (Lg) irradiated from the light source (LA) is directed toward the aberration separation lens (ASL) through a splitter (SPL). That is, a splitter (SPL) may be arranged on the propagation path of the light (Lg) so that the propagation path of the light (Lg) is changed so that the light (Lg) is directed toward the aberration separation lens (ASL).

Referring to FIG. 2 together, a plurality of transmitted lights (TLg) passing through an aberration separation lens (ASL) can be provided to an inspection target (200) including a plurality of layers (L1, L2, L3) (S200). The light passing through the aberration separation lens (ASL) can include a first transmitted light (TLg1), a second transmitted light (TLg2), and a third transmitted light (TLg3) having different wavelengths. Since the first transmitted light (TLg1), the second transmitted light (TLg2), and the third transmitted light (TLg3) each have different wavelengths, the focal lengths of the first transmitted light (TLg1), the second transmitted light (TLg2), and the third transmitted light (TLg3) can be different. Specifically, the wavelength of the third transmitted light (TLg3) may be longer than the wavelength of the second transmitted light (TLg2), and the wavelength of the second transmitted light (TLg2) may be longer than the wavelength of the first transmitted light (TLg1). Accordingly, the first transmitted light (TLg1) may be focused on the upper surface of the first layer (L1) and reflected from the upper surface of the first layer (L1), the second transmitted light (TLg2) may be focused on the upper surface of the second layer (L2) and reflected from the upper surface of the second layer (L2), and the third transmitted light (TLg3) may be focused on the upper surface of the third layer (L3) and reflected from the upper surface of the third layer (L3).

Referring to FIGS. 1 and 3 together, a plurality of transmitted lights (TLg) may be provided as reflected lights (RLg) reflected from the first to third layers (L1, L2, L3) to a plurality of color filters (CF) (S300). The plurality of color filters (CF) may include a first color filter (CF1), a second color filter (CF2), and a third color filter (CF3) that transmit lights of different wavelengths. Thereafter, a plurality of color lights (CLg) having different wavelengths may be output from the plurality of color filters (CF) (S400). Specifically, a first color light (CLg1) may be output from the first color filter (CF1), a second color light (CLg2) may be output from the second color filter (CF2), and a third color light (CLg3) may be output from the third color filter (CF3). A plurality of color lights (CLg) separated by wavelength from a plurality of color filters (CF) can be irradiated to a detection unit (100) (S500). The detection unit (100) can include a receiving unit (110) arranged on a plurality of color filters (CF) and a generating unit (120) connected to the receiving unit (110). A first color light (CLg1) transmitted through a first color filter (CF1), a second color light (CLg2) transmitted through a second color filter (CF2), and a third color light (CLg3) transmitted through a third color filter (CF3) can be irradiated to the receiving unit (110).

According to one embodiment of the present invention, the receiving unit (110) may include a plurality of regions. Specifically, the receiving unit (110) may include a first region (A1) corresponding to the first color filter (CF1), a second region (A2) corresponding to the second color filter (CF2), and a third region (A3) corresponding to the third color filter (CF3). The first region (A1) may receive the first color light (CLg1), the second region (A2) may receive the second color light (CLg2), and the third region (A3) may receive the third color light (CLg3). Accordingly, the receiving unit (110) may obtain image information about a portion on the upper surface of the first layer (L1) where the first transmitted light (TLg1) is focused by the first color light (CLg1) received in the first region (A1). In addition, image information about a portion where the second transmitted light (TLg2) is focused on the upper surface of the second layer (L2) can be obtained through the second color light (CLg2) received in the second area (A2). In addition, image information about a portion where the third transmitted light (TLg3) is focused on the upper surface of the third layer (L3) can be obtained.

Hereafter, referring to FIGS. 4A and 4B together, a step (600) may be performed in which the generation unit (120) receives the image information acquired by the reception unit (110) and generates multiple layer-by-layer images of the inspection target (200). The generation unit (120) may generate a first image (IM1), a second image (IM2), and a third image (IM3) using the image information acquired by the reception unit (110). The first image (IM1) may be an image generated from the first area (A1), the second image (IM2) may be an image generated from the second area (A2), and the third image (IM3) may be an image generated from the third area (A3). The step of generating the first image (IM1), the second image (IM2), and the third image (IM3) may further include a step of continuously performing the inspection while moving the inspection target (200, see FIG. 1) in the first direction (DR1) or the second direction (DR2), or while moving the inspection device (1000, see FIG. 1) in the first direction (DR1) or the second direction (DR2). By performing the inspection continuously, the generation unit (120) can generate an entire image (or, first image (IM1)) of the upper surface of the first layer (L1, see FIG. 2) by extracting image information obtained from the first area (A1), can generate an entire image (or, second image (IM2)) of the upper surface of the second layer (L2, see FIG. 2) by extracting image information obtained from the second area (A2), and can generate an entire image (or, third image (IM3)) of the upper surface of the third layer (L3, see FIG. 2) by extracting image information obtained from the third area (A3).

Referring to FIGS. 1 to 5, an inspection method according to an embodiment of the present invention can generate a plurality of transmitted lights (TLg) capable of obtaining image information of first to third layers (L1, L2, L3) of an inspection target (200) through an aberration separation lens (ASL), and can generate a first image (IM1), a second image (IM2), and a third image (IM3) corresponding to images of each of the plurality of layers (L1, L2, L3) of the inspection target (200) from color lights (CLg) having image information through a plurality of color filters (CF). Accordingly, compared to a case where images of the plurality of layers (L1, L2, L3) of the inspection target (200) are respectively obtained through a plurality of cameras, the inspection process can be simplified and the inspection time can be shortened.

Although the present invention has been described above with reference to preferred embodiments thereof, it will be understood by those skilled in the art or having ordinary knowledge in the art that various modifications and changes may be made to the present invention without departing from the spirit and technical scope of the present invention as set forth in the claims below.

Therefore, the technical scope of the present invention should not be limited to the contents described in the detailed description of the specification, but should be defined by the scope of the patent claims.

1000: Inspection device 200: Inspection target
LA: Light source ASL: Aberration separation lens
CF: Color Filter 100: Detection Unit
110: Receiver 120: Generator
TLg: Transmitted light CLg: Color light

Claims (17)

A light source that emits light;
An aberration separation lens disposed on an inspection object including a plurality of layers and generating chromatic aberration in the light emitted from the light source to provide a plurality of transmitted lights having different wavelengths to the inspection object;
A plurality of color filters that separate the reflected light reflected from the inspection target by wavelength and output a plurality of color lights; and
A detection unit is included that receives the plurality of color lights from the plurality of color filters and generates an image of the inspection target,
The above detection unit,
A receiving unit including a plurality of areas respectively corresponding to the plurality of color filters and receiving the plurality of color lights through the plurality of areas; and
An inspection device including a generation unit that generates multiple images for each of the multiple layers of the inspection target using the multiple color lights. In the first paragraph,
An inspection device wherein the plurality of color lights include first color lights, second color lights, and third color lights having different wavelengths. In the second paragraph,
The above multiple color filters are,
A first color filter transmitting the first color light;
A second color filter transmitting the second color light; and
An inspection device including a third color filter that transmits the third color light. In the third paragraph,
The above multiple areas are,
A first area corresponding to the first color filter;
a second area corresponding to the second color filter; and
An inspection device including a third area corresponding to the third color filter. In the fourth paragraph,
Each of the first to third regions extends in the first direction,
An inspection device in which the first to third regions are listed along a second direction that is perpendicular to the first direction. In the fourth paragraph,
An inspection device in which each of the first to third regions has a different size. In the second paragraph,
The above first color light is blue light,
The above second color light is green light,
The above third color light is a red light inspection device. In the second paragraph,
An inspection device in which each of the first color light, the second color light, and the third color light corresponds to an image of each of the plurality of layers of the inspection target. In the first paragraph,
The above plurality of transmitted lights include first transmitted lights, second transmitted lights, and third transmitted lights having different wavelengths,
An inspection device in which the focal lengths of the first transmitted light, the second transmitted light, and the third transmitted light are each different from each other. In Article 9,
The wavelength of the third transmitted light is longer than the wavelength of the second transmitted light,
An inspection device in which the wavelength of the second transmitted light is longer than the wavelength of the first transmitted light. In Article 10,
The focal length of the third transmitted light is longer than the focal length of the second transmitted light,
An inspection device in which the focal length of the second transmitted light is longer than the focal length of the first transmitted light. In the first paragraph,
An inspection device further comprising a splitter that changes the path of light emitted from the light source. In the first paragraph,
The above-mentioned receiver is an inspection device which is an optical image sensor that detects light. A step of providing light output from a light source to an aberration separation lens;
A step of providing a plurality of transmitted lights having different wavelengths through the above-described aberration separation lens to an inspection object including a plurality of layers;
A step of providing each of the plurality of transmitted lights with reflected light reflected from the plurality of layers to a plurality of color filters;
A step of outputting a plurality of color lights having different wavelengths from the plurality of color filters;
A step of providing the above plurality of color lights to a detection unit; and
An inspection method comprising a step of generating a plurality of images for each of the plurality of layers of the inspection target using the plurality of color lights through the detection unit. In Article 14,
An inspection method in which the detection unit includes a receiving unit including a plurality of areas respectively corresponding to the plurality of color filters, and a generating unit generating images of the plurality of layers of the inspection target. In Article 15,
Before the step of generating the above multiple layer images,
An inspection method further comprising a step of each of the plurality of regions receiving a plurality of color lights separated by wavelength. In Article 14,
The step of irradiating light from the above light source to the above aberration separation lens is as follows:
An inspection device further comprising a step of changing the path of light irradiated from the light source through a splitter so that the light is directed to the aberration separation lens.

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