KR102138622B1 - Apparatus for inspecting substrate and method thereof - Google Patents

Abstract

A substrate inspection apparatus according to the present disclosure includes: a first light source that irradiates ultraviolet light toward a coating film of a substrate on which a fluorescent dye is mixed; A first optical sensor that captures fluorescence generated from the coating film irradiated with the ultraviolet light to obtain a two-dimensional image of the substrate; A processor that derives one region among a plurality of regions of the substrate based on the two-dimensional image; A second light source irradiating laser light toward the one region; And a second optical sensor that acquires optical interference data generated from the one region by the laser light, and the processor can derive the thickness of the coating film for the one region based on the optical interference data. .

Description

Substrate inspection device and substrate inspection method {APPARATUS FOR INSPECTING SUBSTRATE AND METHOD THEREOF}

The present disclosure relates to a substrate inspection apparatus and a substrate inspection method.

In a substrate processing process, a substrate may be coated to protect devices on the substrate. Such a coating may be referred to as a conformal coating. The thickness of the conformal coating film may be performed to confirm whether the coating film on the substrate produced by the coating is uniformly applied to a certain thickness.

In order to inspect the thickness of the coating film, a two-dimensional (2 Dimensional) photographic inspection may be performed. The 2D photographing test is to acquire a 2D image of the object and inspect the object, and may include a 2D fluorescence photographing test. However, the 2D photographic inspection can only perform qualitative inspection on the thickness of the coating film, and may not measure the exact thickness value of the coating film. In addition, in the case of a 2D photographic inspection, thickness measurement may be difficult when the coating film is thin (eg, about 30 μm).

In addition, a confocal microscope may be used to inspect the thickness of the coating film. However, measurement by a confocal microscope has a problem that it takes a long time. In addition, for inspecting the thickness of the coating film, it may be possible to measure using OCT (Optical Coherence Tomography). However, the measurement by the OCT is limited in improving both the depth direction resolution and the measurement depth range, and saturation by light used in the OCT occurs at the electrode portion of the device on the substrate, which prevents accurate measurement. Can be

Republic of Korea Patent Publication No. 10-2017-0085279 (2017.07.24.) Republic of Korea Patent Publication No. 10-2014-0133992 (2014.11.21.)

The present disclosure is intended to solve the above-described problems, and provides a technique for measuring the thickness of a coating film on a substrate.

As one aspect of the present disclosure, a substrate inspection apparatus can be proposed. A substrate inspection apparatus according to an aspect of the present disclosure includes: a first light source that irradiates ultraviolet light toward a coating film of a substrate on which a fluorescent dye is mixed; A first optical sensor that captures fluorescence generated from the coating film irradiated with the ultraviolet light to obtain a two-dimensional image of the substrate; A processor that derives one region among a plurality of regions of the substrate based on the two-dimensional image; A second light source irradiating laser light toward the one region; And a second optical sensor that acquires optical interference data generated from the one region by the laser light, and the processor can derive the thickness of the coating film for the one region based on the optical interference data. .

In one embodiment, the processor may derive an application amount of a coating film for each of the plurality of regions based on the 2D image, and determine an area of the plurality of regions having an application amount equal to or less than a predetermined amount as the one region.

In one embodiment, the substrate inspection apparatus further includes a memory for storing information about a region of interest preset by a user, and the processor can determine the region based on the information about the region of interest.

In one embodiment, the region of interest may be a region including electrodes of elements on the substrate.

In one embodiment, the processor may determine, based on the two-dimensional image, an area determined to be defective in the substrate as the one area.

In one embodiment, the memory further stores device arrangement information indicating the arrangement of the devices on the substrate, and the processor may derive an area including the electrode using the device arrangement information.

In one embodiment, the reflected light reflected from the surface of the coating film may be used as a reference light.

In one embodiment, the processor, based on the optical interference data, acquires a cross-sectional image representing a cross section in a first axial direction corresponding to a depth direction of the coating film, and based on a boundary line on the cross-sectional image The thickness of the coating film for one region can be determined.

In one embodiment, the reflectance of the surface of the coating film to the laser light is determined by the fluorescent dye mixing rate of the coating film in which the fluorescent dye is mixed, and the fluorescent dye mixing rate is such that the reflectance exceeds a preset reference value. Can be set to a value.

In one embodiment, the coating film may be formed of at least one material selected from acrylic, urethane, polyurethane, silicone, epoxy, UV (Ultra Violet) curing material and IR (Infra Red) curing material.

In one embodiment, the surface of the coating film may be formed as a curved surface.

As one aspect of the present disclosure, a substrate inspection method can be proposed. A substrate inspection method according to an aspect of the present disclosure includes: irradiating ultraviolet rays toward a coating film of a substrate on which a fluorescent dye is mixed; Capturing fluorescence generated from the UV-irradiated coating film to obtain a two-dimensional image of the substrate; Deriving one region of the plurality of regions of the substrate based on the two-dimensional image; Irradiating laser light toward the one area and obtaining light interference data generated from the one area by the laser light; And deriving the thickness of the coating film for the one region based on the optical interference data.

In one embodiment, the step of deriving a region comprises: deriving an application amount of a coating film for each of the plurality of regions based on the two-dimensional image; And determining an area of the plurality of areas having an application amount equal to or less than a predetermined amount as the one area.

In one embodiment, the step of deriving a region may include: determining the one region based on information about a region of interest preset by a user.

In one embodiment, the region of interest may be a region including electrodes of elements on the substrate.

In one embodiment, the step of deriving a region may include determining a region determined to be defective in the substrate as the one region based on the two-dimensional image.

In one embodiment, a region including an electrode may be derived based on device arrangement information indicating an arrangement of the devices on the substrate.

In one embodiment, the reflected light reflected from the surface of the coating film may be used as reference light.

In one embodiment, deriving the thickness of the coating film for a region comprises: obtaining a cross-sectional image showing a cross section in a first axial direction corresponding to a depth direction of the coating film based on the optical interference data; And determining the thickness of the coating film for the one region based on the boundary line on the cross-sectional image.

In one embodiment, the reflectivity of the surface of the coating film for laser light is determined by the fluorescent dye mixing rate of the coating film in which the fluorescent dye is mixed, and the fluorescent dye mixing rate is a value such that the reflectance exceeds a preset reference value. Can be set to

In one embodiment, the coating film may be formed of at least one material selected from acrylic, urethane, polyurethane, silicone, epoxy, UV (Ultra Violet) curing material and IR (Infra Red) curing material.

In one embodiment, the surface of the coating film may be formed as a curved surface.

According to various embodiments of the present disclosure, the substrate inspection apparatus can accurately measure the thickness even when the coating film is thinner than a predetermined thickness (for example, about 30 μm).

According to various embodiments of the present disclosure, the substrate inspection apparatus may shorten the time required to measure the thickness of the entire coating layer through sampling a specific area.

1 is a view showing an embodiment of a process of operating a substrate inspection apparatus according to the present disclosure.
2 is a block diagram of an inspection apparatus according to various embodiments of the present disclosure.
FIG. 3 is a diagram illustrating a process in which an inspection apparatus derives an area to be measured by OCT according to an element arrangement according to an embodiment of the present disclosure.
4 is a diagram illustrating a process in which an inspection apparatus derives an OCT measurement target region according to a defect region according to an embodiment of the present disclosure.
5 is a diagram illustrating a process of additionally measuring a peripheral area of an OCT measurement target area from which an inspection device is derived, according to an embodiment of the present disclosure.
6 is a view showing a first OCT part, according to an embodiment of the present disclosure.
7 is a view showing a second OCT part, according to an embodiment of the present disclosure.
8 is a view illustrating a cross-sectional image and a boundary line appearing on the cross-sectional image, according to an embodiment of the present disclosure.
9 is a view showing a measurement range of a first OCT part and a second OCT part, according to an embodiment of the present disclosure.
10 is a view showing an embodiment of a substrate inspection method, which may be performed by an inspection device according to the present disclosure.

The various embodiments described in this document have been exemplified for the purpose of clearly describing the technical spirit of the present disclosure, and are not intended to be limited to the specific embodiments. The technical spirit of the present disclosure includes various modifications, equivalents, alternatives, and alternatively selectively combined embodiments of each embodiment described in this document. In addition, the scope of rights of the technical spirit of the present disclosure is not limited to various embodiments or detailed descriptions thereof.

Terms used in this document, including technical or scientific terms, may have meanings generally understood by those skilled in the art to which the present disclosure pertains, unless otherwise defined.

Expressions such as “include”, “can include”, “have”, “can have”, “have”, “can have”, etc., are used in this document, such as targeted features (eg Function, operation or component, etc.), and does not exclude the presence of other additional features. That is, such expressions should be understood as open-ended terms that imply the possibility of including other embodiments.

The expression of the singular used in this document may include the meaning of the plural unless the context means otherwise, and the same applies to the expression of the singular described in the claims.

Expressions such as "first", "second", or "first" and "second" used in this document distinguish one object from another when referring to a plurality of homogeneous objects, unless the context indicates otherwise. It is used to do this, and it does not limit the order or importance between the objects.

As used herein, "A, B, and C", "A, B, or C", "A, B, and/or C" or "A, B, and C at least one", "A, B , Or “at least one of C”, “at least one of A, B, and/or C”, etc., may mean each listed item or all possible combinations of the listed items. For example, “at least one of A or B” may refer to (1) at least one A, (2) at least one B, (3) at least one A, and at least one B.

As used in this document, the expression "based on" is used to describe one or more factors affecting the action or action of a decision or judgment, as described in a phrase or sentence containing the expression. It does not exclude additional factors affecting the action or action of the decision, judgment.

As used herein, the expression that a component (eg, a first component) is “connected” or “connected” to another component (eg, a second component) means that any component is It may mean not only being directly connected or connected to other components, but also connected or connected through other new components (eg, a third component).

The expressions "configured to" used in this document are "configured to", "having the ability to do", "modified to do", "created to do", It can have the meaning. The expression is not limited to the meaning of “specially designed in hardware”, and for example, a processor configured to perform a specific operation is a general-purpose processor capable of performing the specific operation by executing software. Can mean

To describe various embodiments of the present disclosure, orthogonal coordinate systems having X, Y and Z axes orthogonal to each other may be defined. As used in this document, the expressions such as "X-axis direction", "Y-axis direction", and "Z-axis direction" of a Cartesian coordinate system are both extended by each axis of the Cartesian coordinate system, unless specifically defined otherwise in the description. Can mean direction. In addition, a + sign in front of each axis direction may mean a positive direction in either direction extending in the corresponding axis direction, and a-sign in front of each axis direction extends in the corresponding axis direction. It may mean the negative direction, which is the other of the two directions.

In the present disclosure, a substrate is a plate or container on which devices such as semiconductor chips are mounted, and may serve as a connection path between devices and electrical signals between devices. The substrate may be used for the manufacture of integrated circuits, etc., and may be made of a material such as silicon. For example, the substrate may be a printed circuit board (PCB), and may be referred to as a wafer according to an embodiment.

In the present disclosure, the coating film may be a thin film produced on the substrate by coating to protect devices on the substrate. If the coating film is thick, the film may break, and may affect the operation of the substrate. Therefore, it is necessary to prevent the coating film from being broken by applying the coating film relatively thinly and evenly. In one embodiment, the coating film may be formed of at least one material selected from acrylic, urethane, polyurethane, silicone, epoxy, UV (Ultra Violet) curing material and IR (Infra Red) curing material. The coating film formed of the above-described material may have a higher reflectance on the surface of the coating film and/or a back scattering rate of the coating film, which will be described later, compared to the coating film which is not.

In the present disclosure, optical coherence tomography (OCT) may be an imaging technique for capturing an image in an object by using an interference phenomenon of light. An image representing the inside of the object in the depth direction from the surface of the object may be obtained using the OCT. In general, it is based on an interferometer, and depending on the wavelength of light used, a depth direction resolution for an object may be changed. Compared to other optical techniques, confocal microscopes, images can be acquired by penetrating deeper into an object.

Hereinafter, various embodiments of the present disclosure will be described with reference to the accompanying drawings. In the accompanying drawings and description of the drawings, identical or substantially equivalent components may be given the same reference numerals. In addition, in the following description of various embodiments, the same or corresponding elements may be omitted repeatedly, but this does not mean that the corresponding elements are not included in the embodiment.

1 is a view showing an embodiment of a process of operating a substrate inspection apparatus according to the present disclosure. The substrate inspection apparatus according to the present disclosure may be implemented by the inspection apparatus 10 according to various embodiments. The inspection apparatus 10 according to various embodiments of the present disclosure may measure the thickness of a coating film applied to a substrate. In one embodiment, the inspection device 10 performs a photographing inspection using a fluorescent dye on the entire area of the substrate, derives a specific area according to a predetermined criterion, and additionally measures thickness by OCT on the derived area It can be done.

First, the inspection apparatus 10 may perform a photographing inspection using a fluorescent dye on the substrate 2. The photographing test may be a fluorescence photographing test. For this inspection, a fluorescent dye may be premixed in the coating film applied on the substrate 2. The first light source 130 of the inspection device 10 may irradiate ultraviolet light toward the coating film of the substrate. The irradiated ultraviolet light may excite the fluorescent dye mixed in the coating film to generate fluorescence. The first optical sensor 140 of the inspection device 10 captures the fluorescence to obtain a two-dimensional image of the coating film of the substrate. The 2D image may be a 2D fluorescent image according to an embodiment.

The inspection apparatus 10 may derive one or more regions 3 on the substrate 2 according to a predetermined criterion based on the result of the photographing inspection. In one embodiment, the inspection apparatus 10 may derive an application amount of a coating film applied to each region of the substrate 2 from a two-dimensional image, and a certain region 3 based on the derived application amount have. Also, in one embodiment, the two-dimensional image may represent a device mounted on the substrate 2, a predetermined feature or defect on the substrate generated according to various processes, and the inspection device 10 may It is also possible to derive a certain region 3 as a basis.

Thereafter, the inspection apparatus 10 may additionally perform thickness measurement on the derived region 3 using the OCT. The OCT part 170 of the inspection device 10 acquires optical interference data for the derived area 3, and based on the acquired optical interference data, the thickness of the coating film applied to the corresponding area 3 on the substrate Can be further measured.

In one embodiment, the inspection device 10 can derive an important area to be protected with a coating film on the substrate 2 from the two-dimensional image. An important area to be protected by a coating film may be, for example, an area including an electrode part of a component, and this important area may be derived by comparing information stored in a memory with a two-dimensional image. The inspection device 10 may additionally perform thickness measurement using the OCT on the derived important area.

In one embodiment, the inspection device 10 may perform thickness measurement using the OCT part 170 on a region of interest preset by the user. The memory of the inspection device 10 may store information on a region of interest preset by a user, and the processor of the inspection device 10 performs thickness measurement by using OCT on the region corresponding to the region of interest based on this information You can decide which area to do. In one embodiment, the region of interest may be a region including the above-described component or electrode portion of the device. In one embodiment, the process of deriving the portion corresponding to the region of interest may be performed using a two-dimensional image of the substrate.

In the present disclosure, the optical interference data is obtained from the interfering light generated when the irradiated light reflects the measured light reflected from the object and the reference light reflected from the reference mirror or the like in the object measurement according to the OCT method. Data. Interference may occur depending on the characteristics of the measurement light and the reference light (optical path, wavelength, etc.), and the optical sensor may capture the interference phenomenon to obtain optical interference data. In addition, based on the optical interference data, a cross-sectional image showing a cross section in the depth direction of the coating film may be generated. Optical interference data may be referred to as an interference signal.

According to various embodiments of the present disclosure, the inspection device 10 may measure the exact thickness of the coating film by utilizing the OCT part 170. In addition, the inspection device 10 can measure the thickness of a thin coating film, for example, a coating film having a thickness of about 30 μm or less.

According to various embodiments of the present disclosure, the inspection apparatus 10 derives a coating amount of each of the regions of the substrate 2 through a two-dimensional image of the substrate 2 and determines a specific region according to a predetermined criterion. By sampling and additionally performing thickness measurement in a specific area through the OCT part 170, it is possible to accurately measure thickness unlike a two-dimensional imaging test, and at the same time, the measurement time compared to measuring the thickness of the entire coating film using the OCT. This can be shortened.

2 is a block diagram of an inspection apparatus 10 according to various embodiments of the present disclosure. The substrate inspection apparatus according to the present disclosure described above may be represented by the illustrated inspection apparatus 10. According to one embodiment, the inspection device 10 may include a first light source 130, a first light sensor 140, a second light source 150, a second light sensor 160, a processor 110 and/or memory It may include 120. In some embodiments, at least one of these components of the testing device 10 may be omitted, or other components may be added to the testing device 10. In some embodiments, in addition to or alternatively, some of the components may be integrated or implemented in singular or plural entities.

At least some of the internal and external components of the test device 10 are connected to each other through a bus, general purpose input/output (GPIO), serial peripheral interface (SPI), or mobile industry processor interface (MIPI). , Data and/or signals.

The first light source 130 may irradiate ultraviolet light toward the coating film of the substrate 2 on which the fluorescent dye is mixed. The first light source 130 may be arranged to irradiate ultraviolet light toward the substrate, and the relative position of the first light source 130 with respect to the substrate, the irradiation angle of the ultraviolet light, and the brightness of the ultraviolet light may be variously configured (configured) Can. In one embodiment, the inspection device 10 may include a plurality of first light sources 130.

The first photodetector 140 may capture fluorescence generated from the coating film of the substrate 2 by irradiated ultraviolet rays. When the fluorescent dye in the coating film is excited by the specifically irradiated ultraviolet light, fluorescence is generated. The first photodetector 140 captures the fluorescence to obtain a two-dimensional image of the coating film of the substrate 2. In one embodiment, the inspection device 10 may include a plurality of first light sensors 140. The first optical sensor 140 may be implemented by a CCD (Charged Coupled Device) or a Complementary Metal-Oxide-Semiconductor (CMOS).

The processor 110 may control at least one component of the inspection device 10 connected to the processor 110 by driving software (eg, a program). In addition, the processor 110 may perform various operations related to the present disclosure, such as processing, data generation, and processing. In addition, the processor 110 may load data or the like from the memory 120 or store it in the memory 120.

The processor 110 may derive one region among a plurality of regions of the substrate 2 based on the two-dimensional image acquired by the first photo sensor 140. One area can be derived according to a predetermined criterion. The substrate 2 may be divided into a plurality of regions. The plurality of regions are regions that virtually divide the surface of the substrate 2, and may be regions that are previously divided according to a predetermined criterion.

In one embodiment, the processor 110 may derive an application amount of a coating film for each of a plurality of regions of the substrate 2, and may derive one region described above based on the application amount. Specifically, the processor 110 may obtain luminance information for each of a plurality of regions of the substrate 2 from the obtained two-dimensional image. In the present disclosure, the luminance may mean a light intensity per unit area of one surface that reflects any one light source or light, that is, the amount of light emitted from the unit area. The luminance information for one region may be information representing luminance of fluorescence generated by the region. The processor 110 may derive an application amount of a coating film applied to each of a plurality of regions of the substrate 2 based on the obtained luminance information. The coating film of the substrate 2 may have features such as unevenness and curvature, depending on the elements existing on the substrate 2, predetermined characteristics or defects on the substrate 2, or the degree to which the coating film is evenly distributed. Depending on features such as unevenness and curvature of the substrate 2, the amount of fluorescent dye applied to each region of the coating film may be different. When ultraviolet light is irradiated, luminance in each region of the coating film may vary according to the amount of fluorescent dye. The processor 110 may derive the coating amount of the coating film in each region using the luminance of each region. The processor 110 may derive a region (eg, a first region) in which a coating amount of the coating film is equal to or less than a predetermined amount, among a plurality of regions of the substrate 2. The preset amount may be determined according to a designer's intention, and information on this may be stored in the memory 120.

The processor 110 may control the OCT part 170 to measure the thickness of the coating film of one derived area (eg, the first area). The processor 110 may acquire optical interference data (eg, first optical interference data) according to interference light generated from one derived region (eg, the first region). The processor 110 may derive the thickness of the coating film for one derived region (eg, the first region) using the obtained optical interference data (eg, the first optical interference data).

The OCT part 170 may include a second light source 150 and/or a second light sensor 160. Specifically, the processor 110 may control the second light source 150 and the second light sensor 160 to perform the above-described operation. The OCT part 170 may be implemented in various types, which will be described later.

The second light source 150 may irradiate laser light toward the coating film of the substrate 2. The arrangement of the second light source 150, the relative position with respect to the substrate, and the like may be variously configured (configured), and in particular, may be implemented differently depending on the type of the OCT part 170. In one embodiment, the second light source 150 may use a laser capable of changing the wavelength in a short time, and by using this, optical interference data corresponding to different wavelengths may be obtained. In one embodiment, the inspection device 10 may include a plurality of second light sources 150. The second light source 150 is controlled by the processor 110 and may irradiate laser light toward the above-described derived region (eg, the first region).

The second photo sensor 160 may capture interference light generated from the coating film by laser light. In detail, when the first OCT part to be described later is used, the second optical sensor 160 captures interference light generated by reflected light (reference light) from which the laser light is reflected by the reference mirror and measurement light reflected from the coating film. can do. A cross-sectional image of the reference mirror surface may be generated using the optical interference data obtained by capturing the interference light. In addition, when a second OCT part to be described later is used according to an embodiment, the second light detector 160 is transmitted by the reflected light reflected from the surface of the coating film and the backscattered light after being transmitted to a predetermined depth from the coating film. The generated interference light can be captured. Here, the reflected light reflected from the surface of the coating film may serve as a reference light, and the scattered light may serve as a measurement light. Using the interference data obtained by capturing the interference light, a cross-sectional image based on the surface of the coating film may be generated. In one embodiment, the inspection device 10 may include a plurality of second optical sensors 160. The second photo sensor 160 may be implemented by CCD or CMOS. The second optical sensor 160 is controlled by the processor 110, and the optical interference data according to the interference light generated from the one region (for example, the first region, etc.) derived by the laser light (for example, 1 optical interference data, etc.).

The memory 120 can store various data. The data stored in the memory 120 may include software (eg, a program) as data acquired, processed, or used by at least one component of the inspection device 10. The memory 120 may include volatile and/or nonvolatile memory. The memory 120 may store data obtained from the first photo sensor 140 and the second photo sensor 160. Also, the memory 120 may store luminance information of each region of the substrate 2 derived from the two-dimensional image, and/or thickness information of the coating film derived by the processor 110. In addition, the memory 120 includes device array information 1000, device density information 2000, predetermined characteristics on the substrate, information about defect areas, electrode location information on the board 3000, and a region of interest preset by the user. It may be storing information about the information in advance.

In the present disclosure, the device arrangement information 1000 may be information indicating an arrangement of devices disposed on the substrate 2. The device array information 1000 may indicate information such as the position, direction, and size of devices mounted on the substrate 2 on the substrate 2. The device array information 1000 may be a basis for adjusting the luminance information described above or for specifying a predetermined area on the substrate. In one embodiment, the inspection device 10 may derive the coating amount of the coating film for each of a plurality of regions of the substrate, based on the device arrangement information and the two-dimensional image.

In the present disclosure, the device density information 2000 may be information indicating the degree of density of devices on the substrate 2. The device density information 2000 considers the ratio of the area occupied by objects such as devices, electrode of devices, solder balls, metal wires, lead frames, etc. for each area on the substrate 2, and the degree of density of devices in each area Can represent. The device density information 2000 may be derived based on the device array information 1000.

In the present disclosure, the program is software stored in a memory, and may include an operating system for controlling resources of the inspection device, middleware that provides various functions to applications so that applications and/or applications can utilize resources of the inspection device. Can.

In one embodiment, the inspection device 10 may further include a communication interface (not shown). The communication interface may perform wireless or wired communication between the inspection device 10 and other servers or inspection devices 10 and other external electronic devices. For example, the communication interface is long-term evolution (LTE), LTE Advance (LTE-A), code division multiple access (CDMA), wideband CDMA (WCDMA), wireless broadband (WiBro), wireless fidelity (WiFi), Bluetooth (Bluetooth), NFC (near field communication), GPS (Global Positioning System) or GNSS (global navigation satellite system) can perform wireless communication according to the method. For example, the communication interface may perform wired communication according to a method such as universal serial bus (USB), high definition multimedia interface (HDMI), recommended standard232 (RS-232), or plain old telephone service (POTS).

In one embodiment, the processor 110 may obtain information from the server by controlling the communication interface. Information obtained from the server may be stored in the memory 120. In one embodiment, the information obtained from the server includes the above-described device array information 1000, device density information 2000, predetermined characteristics on the substrate, information on defect areas, electrode location information on the substrate 3000, and the user. It may include information about a region of interest preset in advance.

In one embodiment, the inspection device 10 may further include an input device (not shown). The input device may be a device that receives data for transmission to at least one component of the inspection device 10 from the outside. The input device may receive information on a user's region of interest from the user. For example, the input device may include a mouse, a keyboard, and a touch pad.

In one embodiment, the inspection device 10 may further include an output device (not shown). The output device may be a device that provides various types of data, such as test results of the inspection device 10 and an operation state, to a user in a visual form. For example, the output device can include a display, a projector, a hologram, and the like.

In one embodiment, the inspection device 10 may be various types of devices. For example, the inspection device may be a portable communication device, a computer device, a portable multimedia device, a wearable device, or a device according to one or more of the above-described devices. The inspection device of the present disclosure is not limited to the devices described above.

Various embodiments of the inspection apparatus 10 according to the present disclosure can be combined with each other. Each of the embodiments can be combined according to the number of cases, and embodiments of the inspection device 10 made in combination are also within the scope of the present disclosure. In addition, the internal/external components of the inspection apparatus 10 according to the present disclosure described above may be added, changed, replaced or deleted according to embodiments. In addition, the internal/external components of the above-described inspection device 10 may be implemented as hardware components.

FIG. 3 is a diagram illustrating a process in which the inspection apparatus 10 derives an OCT measurement target area according to an element arrangement according to an embodiment of the present disclosure. In one embodiment, the processor 110 derives a region (eg, a first region) having an application amount of less than or equal to a predetermined amount, and a region (eg, a second region) having the same or similar arrangement of elements derived through a two-dimensional image , By controlling the OCT part 170, the thickness for this area (eg, the second area) can be derived. In other words, the processor 110 may derive a region in which the arrangement of elements is the same or similar based on the element arrangement information 1000, and perform thickness measurement using the OCT for the region.

In regions where the device arrangement is the same or similar, the thickness value of the applied coating film may be similar. When an area is determined to be less than or equal to a preset amount in an inspection through a two-dimensional image, a region having the same or similar device arrangement as the one area may have a similar coating film coating amount. Accordingly, in order to increase the accuracy of the entire coating film thickness inspection, the inspection device 10 may further perform the same operation in this embodiment.

As described above, the processor 110 may derive an area (eg, a first area) 3 in which a coating amount obtained through a two-dimensional image is equal to or less than a preset amount. In one embodiment, the processor 110 may measure the thickness for this region 3 using the OCT part 170.

In addition to this, the processor 110 may derive one region 4 on the substrate 2 having the same device arrangement as the derived region 3. The corresponding area (eg, the second area) 4 may be selected from areas (ie, areas other than the first area) in which the application amount derived through the two-dimensional image exceeds a preset amount. The processor 110 may derive the corresponding region 4 based on the device arrangement information 1000 described above.

The processor 110 may use the OCT part 170 to derive the thickness for the corresponding region 4 derived further. The processor 110 controls the second light source 150 and the second light detector 160 to receive light interference data (eg, second light interference data) generated by laser light reflected from the corresponding area 4. Can be obtained. The processor 110 may derive the thickness of the coating film applied to the corresponding area 4 based on the acquired optical interference data. In the present disclosure, the processor 110 controls the second light source 150 and the second light sensor 160 to obtain light interference data in one area, so that the second light source 150 lasers toward the corresponding area. It may mean that the light is irradiated, and the second optical sensor 160 acquires optical interference data according to the interference light generated from the corresponding region.

In one embodiment, the processor 110 may derive an area 4 having a device arrangement similar to that of the area 3 derived by the 2D image, and perform thickness measurement using the OCT on the area 4 have. Here, whether the device arrangement is similar may be determined based on the device arrangement information 1000 for the two regions 3 and 4. The processor 110 calculates the similarity of the device arrangement for the two regions based on the area occupied by the elements in the regions 3 and 4, the arrangement of the elements, the type, the shape, and the electrode positions of the elements, and the calculated similarity Accordingly, it is possible to determine whether the device arrangements of the two regions are similar.

In one embodiment, the processor 110 may adjust the above-described luminance information according to the arrangement of elements on the substrate 2 and the degree to which the elements are concentrated, and derive a coating amount of the coating film of the corresponding area based on the adjusted luminance information. have. Specifically, the processor 110 may obtain device array information 1000 indicating an array of devices on the substrate 2 from the memory 120. The processor 110 may derive device density information 2000 for each region on the substrate 2 based on the device arrangement information 1000 described above. The processor 110 may adjust luminance information derived from the two-dimensional image based on the device density information 2000. In the region where the device density is high in the substrate 2, application of the fluorescent dye may be uneven. The device density is high, that is, in the region where the device is dense, the luminance can be measured high due to accumulation of the fluorescent dye. The processor 110 may adjust the obtained luminance information in consideration of distortion of luminance according to device density. Accumulated information indicating the relationship between device density and luminance may be used for this adjustment, and the information may be databased and stored in the memory 120. The processor 110 may derive the coating amount for each region on the substrate 2 based on the adjusted luminance information.

4 is a diagram illustrating a process in which the inspection apparatus 10 derives an OCT measurement target area according to a defect area according to an embodiment of the present disclosure. In one embodiment, the processor 110 derives an area (eg, a third area) 5 that is determined to be defective on the substrate 2 based on the device array information 1000 and/or a two-dimensional image, and , By controlling the OCT part 170, the thickness for this area (eg, the third area) can be derived.

In the case of a predetermined defect of the substrate 2 or the coating film, for example, a crack, peeling, irregularity, bending, etc., there may be an error in measuring the coating amount through a two-dimensional photographic inspection. Accordingly, the region 5 determined to have a predetermined defect based on the device array information 1000 and/or the two-dimensional image may be further measured by coating film thickness using the OCT part 170.

The processor 110 may determine an area 5 determined to have a predetermined defect on the substrate 2 based on the device array information 1000 and/or a two-dimensional image obtained from the memory 120. The 2D image may be a photograph of the shape of the actual substrate 2 and the coating film. The device array information 1000 may indicate the shape of the substrate 2 and the expected coating type of the coating film according to a specific specification. The processor 110 may determine a region in which the current substrate 2 and the coating film have characteristics out of a predetermined standard by comparing the device array information 1000 with the two-dimensional image. That is, the processor 110 may determine that the corresponding feature is a defect. The processor 110 may derive an area 5 in which the defect is present.

The processor 110 may derive the thickness for the derived region 5 using the OCT part 170. The processor 110 controls the second light source 150 and the second light detector 160 to receive optical interference data (eg, third optical interference data) generated by laser light reflected from the corresponding region 5. Can be obtained. The processor 110 may derive the thickness of the coating film applied to the corresponding region 5 based on the acquired optical interference data (eg, third optical interference data).

In one embodiment, the derivation of the additional measurement target area based on the defect area may be performed independently of the derivation of the additional measurement target area based on the two-dimensional image described above.

Also, in one embodiment, the processor 110 derives an area (eg, a fourth area) including an electrode part based on the electrode position information 3000 indicating the position of the electrodes of the devices on the substrate 2. , By controlling the OCT part 170, it is possible to perform additional thickness measurement for this area (eg, the fourth area). In the present disclosure, the electrode location information 3000 may indicate the location of the electrodes of the devices on the substrate 2. For example, each of the devices may have an electrode portion for connecting fine wiring on the device and the substrate. This electrode may also be called the leg of the device or chip. The electrode location information 3000 may indicate where the electrodes of the device are located on the substrate 2. In general, the electrode portion of the device may have a phenomenon of agglomeration of fluorescent dyes depending on the density of the device legs, and accordingly, thickness measurement based on a two-dimensional image may not be accurate. Accordingly, the portion where the electrode of the device is located can be further measured using OCT to increase the accuracy of the entire thickness measurement process.

The processor 110 may know where the electrodes of the elements are located on the substrate 2 based on the electrode location information 3000 obtained from the memory 120. The processor 110 may derive an area (eg, a fourth area) on the substrate 2 on which the electrode is located. In one embodiment, the corresponding area (eg, the fourth area) may be selected from areas (ie, areas other than the first area) in which the amount of coating obtained through the two-dimensional image exceeds a preset amount.

The processor 110 may derive the thickness for the derived region (eg, the fourth region) using the OCT part 170. The processor 110 controls the second light source 150 and the second light detector 160 to generate optical interference data (eg, fourth light) generated by laser light reflected from the corresponding area (eg, the fourth area). Interference data). The processor 110 may derive the thickness of the coating film applied to the corresponding region (eg, the fourth region) based on the acquired optical interference data (eg, the fourth optical interference data).

5 is a diagram illustrating a process of additionally measuring a peripheral area of an OCT measurement target area from which the inspection apparatus 10 is derived, according to an embodiment of the present disclosure. In the regions on the substrate 2 derived according to various embodiments of the present disclosure, that is, the regions 7 in which thickness measurement is additionally performed using the OCT, the inspection apparatus 10 is provided with the regions 7 Further thickness measurements can also be performed on the adjacent regions 8 using OCT.

The derived regions 7 are places where thickness measurement using an OCT can be performed in addition to a two-dimensional photographic inspection in terms of accuracy of coating film thickness measurement. The adjacent regions of the regions 7 may have properties similar to those of the region 7 with respect to the substrate 2 or the coating film. Accordingly, in order to secure the accuracy of the entire thickness measurement process, additional thickness measurement using an OCT may be performed on an adjacent region.

Here, when the substrate 2 is divided into a plurality of regions, the adjacent regions may refer to regions located adjacent to the corresponding region 7. In one embodiment, the adjacent area may mean an area of the plurality of areas that is in contact with the corresponding area 7. In one embodiment, the adjacent area may mean an area located within a predetermined radius based on the center of the area 7 among the plurality of areas. In one embodiment, when the axes corresponding to the horizontal and vertical directions of the substrate are respectively referred to as x-axis and y-axis, adjacent regions are in the +x-axis direction, -x-axis direction, and +y-axis direction of the corresponding region 7, It may be an area located in the -y axis direction and sharing a boundary with the corresponding area 7. In one embodiment, the adjacent area may include an area that shares a vertex with the corresponding area 7 among a plurality of areas and is located diagonally.

In one embodiment, the processor 110 may perform thickness measurement using the OCT again based on the coating amount derived by the two-dimensional image and the thickness value measured by the OCT part 170. According to an embodiment, a difference value between a qualitative thickness value of a coating film of a corresponding region that can be derived from an application amount and a thickness value measured by OCT is derived, and when the difference value is greater than or equal to a predefined value, for the corresponding region Thickness measurement using OCT can be performed again. In addition, according to an embodiment, based on the derived coating amount and thickness value, when two values do not satisfy a predetermined criterion, thickness measurement may be performed again. Here, the predetermined criterion may be a criterion used to determine that at least one value of the derived coating amount or thickness is measured incorrectly based on the relationship between the predetermined coating amount and the thickness. That is, when considering the coating amount and thickness value, if it is determined that there is an error in the measurement, the measurement may be performed again. In addition, in one embodiment, the processor 110 is based on the coating amount of one region derived by the two-dimensional image and the thickness value of the region measured by the OCT part 170, with respect to the adjacent region of the region , It is possible to re-measure the thickness by controlling the OCT part 170.

6 is a view showing a first OCT part, according to an embodiment of the present disclosure. The aforementioned OCT part 170 may be implemented as a first OCT part or a second OCT part according to an embodiment.

The first OCT part may further include a reference mirror 172 and a beam splitter 171 in addition to the second light source and the second light sensor. The beam splitter 171 may adjust the optical path of the laser light emitted from the second light source 150, and the reference mirror 172 may reflect the laser light transmitted from the beam splitter 171 to generate a reference light. The first OCT part acquires light interference data from measurement light reflected by the laser film by the coating film of the substrate 2 and interference light formed by interference of the reference light reflected by the reference mirror 172 with the laser light. Can be used.

Specifically, the second light source 150 may irradiate laser light. In one embodiment, the second light source 150 may directly irradiate laser light toward the beam splitter 171. In one embodiment, the second light source 150 transmits laser light through the optical fiber 174 to the convex lens 173, and the laser light passing through the convex lens 173 is transmitted toward the beam splitter 171 Can be.

The beam splitter 171 adjusts the optical path to pass the portion of the laser light received from the second light source 150 to the coating film of the substrate 2, and also reflects the other portion of the laser light to the reference mirror 172 You can adjust the optical path to do so.

Part of the laser light whose optical path is adjusted to face the coating film of the substrate 2 may be reflected from the coating film of the substrate 2. As described above, the laser light may be reflected from the surface of the coating film, or may be backscattered after being transmitted from the surface of the coating film to a predetermined depth according to the wavelength of the laser light. The reflected light or scattered light may be referred to as measurement light. The measurement light may be directed toward the beam splitter 171 and transmitted to the second light detector 160 by the beam splitter 171.

The other portion of the laser light whose optical path is adjusted to face the reference mirror 172 may be reflected by the reference mirror 172. This reflected light can be referred to as a reference light. The reference light may pass through the beam splitter 171 and be transmitted to the second light detector 160.

The second photo sensor 160 may capture interference light formed by the measurement light and the reference light. The second optical sensor 160 may capture the interference light and obtain optical interference data (eg, first optical interference data). The processor 110 obtains this optical interference data from the second optical sensor 160, and generates a cross-sectional image of the coating film based on this, to derive the thickness of the coating film applied to the corresponding area of the substrate 2 have.

7 is a view showing a second OCT part, according to an embodiment of the present disclosure. The second OCT part may include a second light source 150 and/or a second light sensor 160. The second OCT part may not require the reference mirror 172 and the beam splitter 171. In the second OCT part, the reflected light reflected by the surface of the coating film of the substrate 2 and the scattered light back scattered from the interface between the coating film and the substrate 2 on which the coating film is applied as the laser light passes through the coating film. It can be used to obtain optical interference data from interference light formed by interference. Here, the reflected light reflected from the surface of the coating film may serve as the reference light described above, and the scattered light may serve as the measurement light.

Specifically, the second light source 150 may irradiate laser light toward the coating film of the substrate 2. At this time, laser light may be irradiated along the first direction. The first direction may be a direction corresponding to a straight line inclined at a predetermined angle from the normal direction of the substrate. Depending on the embodiment, the first direction may be the same as the normal direction of the substrate. The axis corresponding to the normal direction of the substrate can be said to be the z-axis. The z-axis direction may be a direction corresponding to the depth direction of the coating film. As described above, the second light source 150 may directly irradiate the laser light, but may also irradiate the laser light through the optical fiber 174 and/or the convex lens 173.

The laser light can be reflected from the surface of the coating film. Specifically, the laser light can be reflected from the illustrated first surface. In addition, the laser light may pass through the coating film, and may be scattered back at the interface between the coating film and the substrate on which the coating film is applied. Specifically, the laser light may be scattered back on the second surface shown. The above-mentioned reflected light and scattered light form interference light, and the interference light may proceed in the reverse direction of the first direction. That is, the irradiated laser light and the above-described interference light may proceed along the coaxial direction but in opposite directions. The second optical sensor may capture interference light traveling in the reverse direction of the first direction. The second optical sensor 160 may acquire optical interference data (eg, first optical interference data) from the captured interference light. The processor 110 may obtain the optical interference data from the second photodetector 160 and generate a cross-sectional image based on this to derive the thickness of the coating film applied to the corresponding area of the substrate 2.

In the thickness measurement according to the second OCT part, the above-described reflected light and scattered light may each serve as the reference light and the reflected light of the first OCT part. That is, the surface of the coating film itself may serve as the reference mirror 172 of the first OCT part.

In one embodiment, when the reflectance of the surface of the coating film is greater than or equal to a predetermined reference value, an OCT part of the same type as the second OCT part may be used. The predetermined reference value may be a minimum reflectance required for the surface of the coating film to serve as the reference mirror 172. In one embodiment, the irradiation angle of the irradiated laser light may be adjusted so that the reflectivity of the surface of the coating film is greater than or equal to a reference value. In one embodiment, laser light may be irradiated to an area where the surface of the coating film is parallel to the substrate so that the reflectivity of the surface of the coating film is greater than or equal to a reference value. In the thickness measurement according to the second OCT part of the present disclosure, the reflectance of the coating film surface may mean a ratio between reflected light generated by reflection from the coating film surface and laser light irradiated to the coating film.

In one embodiment, the reflectivity of the coating film surface may be determined by the fluorescent dye mixing rate of the coating film. In one embodiment, the coating film in which the fluorescent dye is mixed may have a higher reflectance on the surface of the coating film than the substrate that is not. The higher the fluorescent dye mixing ratio of the coating film, the higher the reflectivity of the coating film surface. That is, when a coating film in which a fluorescent dye is mixed is used, the reflectance of the surface of the coating film is increased, and accordingly, thickness measurement according to the second OCT part can be easily performed. In one embodiment, the mixing ratio of the fluorescent dye of the coating film may be set to a value such that the reflectance of the surface of the coating film exceeds a preset reference value. Depending on the embodiment, the reference value may be a minimum reflectance required for the surface of the coating film to perform the role of the reference mirror 172, or may be a value arbitrarily set according to the intention of the operator.

In addition, in one embodiment, the backscattering rate of the coating film may also be determined by the fluorescent dye mixing rate of the coating film. In one embodiment, the coating film in which the fluorescent dye is mixed may have a higher back scattering rate of the coating film compared to a substrate that is not. In the thickness measurement according to the second OCT part of the present disclosure, the back scattering rate of the coating film may mean a ratio between the above-mentioned scattered light back scattered and laser light irradiated to the coating film. The higher the fluorescent dye mixing ratio of the coating film, the higher the backscattering rate of the coating film. That is, when a coating film in which a fluorescent dye is mixed is used, a back scattering rate of the coating film is increased, and accordingly, thickness measurement according to the second OCT part can be easily performed. In one embodiment, the mixing ratio of the fluorescent dye of the coating film may be set to a value such that the back scattering rate of the coating film exceeds a preset reference value.

In one embodiment, the surface of the coating film may be formed as a curved surface. In one embodiment, the surface of the coating film may be formed of a convex curved surface, a concave curved surface, or a curved surface having an arbitrary shape with respect to the substrate. In one embodiment, when the surface of the coating film is curved, the thickness measurement according to the second OCT part can be easily performed compared to the case where the surface of the coating film is flat.

In one embodiment, the second OCT part may not place additional components such as window glass on the coating film of the substrate 2. Since the second OCT part according to the present disclosure uses the reflected light reflected by the surface of the coating film for the same purpose as the reference light, to obtain light interference data, additional elements such as a separate window glass for generating the reference light are additionally required. You may not.

8 is a view illustrating a cross-sectional image and a boundary line appearing on the cross-sectional image, according to an embodiment of the present disclosure. The processor 110 may derive the thickness of the coating film applied to a predetermined area from the acquired optical interference data. The processor 110 may generate a cross-sectional image from the optical interference data and derive the thickness of the coating film using information on the cross-sectional image.

In the present disclosure, a cross-sectional image may mean that a cross-section in a depth direction of an object (coating film) is represented as a two-dimensional image in measuring an object according to the OCT method. The cross-sectional image can be generated based on the measured optical interference data. The cross-sectional image may have boundary lines (border patterns) corresponding to the interface between the air and the coating film and the coating film and the substrate.

Specifically, the processor 110 may acquire a cross-sectional image as illustrated using the optical interference data captured by the second optical sensor 160. The cross-sectional image may be an image showing a cross-section in the -z axis direction, that is, in the depth direction with respect to the substrate 2 and the coating film. That is, the cross-sectional image may represent the inside of the coating film and the substrate, which is transmitted in the depth direction from the surface of the coating film.

The illustrated cross-sectional image 8010 may be a cross-sectional image that can be obtained by the above-described first OCT part. The cross-sectional image 8010 may have one or more boundary lines 8050. Each of the boundary lines 8050 may be a boundary surface between the air and the coating film, that is, a boundary line corresponding to the surface of the coating film, or a boundary line corresponding to the interface between the coating film and the substrate 2 to which the coating film is applied to the electrode. The processor 110 may derive the thickness of the coating film by using a gap between boundary lines corresponding to each boundary surface.

Specifically, when using the first OCT part, a cross-sectional image 8010 based on a reference mirror surface may be obtained. The processor 110 may determine a boundary line indicating an interface between air and a coating layer from the illustrated cross-sectional image 8010. In addition, the processor 110 may determine a boundary line indicating a boundary surface between the coating film and the substrate 2 on which the coating film is applied, from the cross-sectional image 8010. The processor 110 may derive a vertical distance between two determined boundary lines on the cross-sectional image 8010 and determine the vertical distance as the thickness of the coating film. In one embodiment, the processor 110 may determine the derived value as the thickness of the coating film by applying a predetermined scaling factor to the derived vertical distance.

In one embodiment, the processor 110 distinguishes a boundary line representing a boundary surface between air and a coating film and a boundary line representing a boundary surface between the coating film and the substrate 2 from a plurality of boundary lines 8050 appearing on the cross-sectional image 8010. To this end, a predetermined segmentation algorithm can be used. In addition, the processor 110 may perform the above-described boundary separation using the accumulated information indicating the relationship between the boundary between the air, the coating film, and the substrate, which is databaseized and stored in the memory 120, and the boundary line of the cross-sectional image. . In one embodiment, the processor 110 may first determine whether to detect a boundary line (border pattern) from a vertical direction or a horizontal direction of the cross-sectional image 8010 and then detect a boundary line from the determined direction. In one embodiment, the processor 110 may classify the overlapped boundary lines generated by the multiple reflections by detecting the boundary lines and exclude them from deriving the thickness measurement.

Meanwhile, when the second OCT part is used, a cross-sectional image 8020 based on the surface of the coating film may be obtained. The cross-sectional image 8020 may have one or more boundary lines 8040. One of the boundary lines 8040 may be a boundary line corresponding to the interface between the coating film and the substrate 2 to which the coating film is applied to the electrode. The processor 110 may derive the thickness of the coating film by using a gap between the boundary line 8040 and the upper side 8030 of the cross-sectional image 8020.

Specifically, when using the second OCT part, the processor 110 may sense a boundary line 8040 indicating an interface between the coating film and the substrate 2 on which the coating film is applied. The processor 110 may determine a boundary line that first appears in a depth direction from an upper side of the cross-sectional image 8020 as a corresponding boundary line 8040. In addition, in the case of the second OCT part, since the light interference data is generated using the reflected light reflected from the surface of the coating film, the cross-sectional image uses the surface of the coating film as the origin, from the surface of the coating film, in the -z axis direction, that is, in the depth direction. It can represent the cross section of. Therefore, the upper side 8030 of the cross-sectional image 8020 obtained by the second OCT part may correspond to the surface of the coating film. The processor 110 may derive a vertical distance between the detected boundary line 8040 and the upper side 8030 of the cross-sectional image 8020 and determine the vertical distance as the thickness of the coating film. In one embodiment, the processor 110 may determine the derived value as the thickness of the coating layer by applying a predetermined scaling factor to the derived vertical distance.

In one embodiment, the thickness of the coating film of the substrate using the OCT may be performed through vacuum or other media. That is, the laser light irradiation of the OCT part 170 and the movement of the reflected light may be performed through a vacuum or other medium other than air.

9 is a view illustrating a measurement range of a first OCT part and a second OCT part, according to an embodiment of the present disclosure. The illustrated cross-sectional image 9010 may be a cross-sectional image obtained by the first OCT part. The cross-sectional image 9010 may have a boundary line indicating a boundary surface between air and a coating film and a boundary line indicating a boundary surface between a coating film and a substrate (PCB). In addition, the illustrated cross-sectional image 9020 may be a cross-sectional image obtained by the second OCT part. The cross-sectional image 9020 may have a boundary line indicating an interface between the coating film and the substrate (PCB).

In one embodiment, the cross-sectional image 9010 may be larger than the cross-sectional image 9020. That is, the cross-sectional image 9010 may have a larger amount of data than the cross-sectional image 9020. This is because, in the case of measurement by the second OCT part, unlike the first OCT part, since the reflected light reflected from the surface of the coating film is used as the reference light, the measurement range in the depth direction (-z-axis direction) starts from the surface of the coating film. It may be because it is limited.

In the illustrated cross-sectional view 9030, in the case of coating film thickness measurement using the first OCT part, a measurement range 9040 considering both height differences due to devices mounted on the substrate 2 may be required to obtain a meaningful measurement result. . However, in the case of coating film thickness measurement using the second OCT part, a significant thickness measurement result can be obtained even with a measurement range 9050 as much as the maximum expected thickness of the coating film. That is, according to the type of the OCT part 170, the inspection apparatus 10 may reduce a measurement range in a depth direction required for coating film thickness measurement, thereby reducing computational capacity required for processing measurement results and memory required for storage. .

In addition, in the case of measuring the thickness of the coating film using the second OCT part, since the reference mirror 172 is not used, the possibility of measurement error due to saturation of reflected light can be reduced. When the light output of the irradiated light exceeds a certain amount, the light amount of the reflected light also increases, and the interference signal appearing on the light interference data or the cross-sectional image may be saturated. When saturated, the interference signal appears regardless of the interference signal generated by the measurement object, which may interfere with accurate measurement. This saturation phenomenon may occur better in the case of the first OCT part using the reference mirror 172 having a high reflectance. The second OCT part may reduce measurement errors due to saturation by excluding the use of a reference mirror.

10 is a view showing an embodiment of a substrate inspection method, which can be performed by the inspection device 10 according to the present disclosure. Although each step of the method or algorithm according to the present disclosure has been described in a sequential order in the illustrated flow chart, each step may be performed in an order that can be arbitrarily combined by the present disclosure in addition to being performed sequentially. The description according to this flow chart does not exclude that any steps or steps are necessary or desirable, except that changes or modifications to the method or algorithm are not made. In one embodiment, at least some of the steps can be performed in parallel, iteratively or heuristically. In one embodiment, at least some of the steps may be omitted, or other steps may be added.

The inspection apparatus 10 according to the present disclosure may perform a substrate inspection method according to various embodiments of the present disclosure in performing substrate inspection. The substrate inspection method according to an embodiment of the present disclosure includes irradiating ultraviolet rays toward the coating film of the substrate (S100), obtaining a two-dimensional image of the substrate (S200), and a plurality of substrates based on the two-dimensional image Deriving one region of the region (S300), irradiating laser light toward the region, obtaining optical interference data generated from one region (S400), and/or based on the optical interference data, one region It may include the step of deriving the thickness of the coating film for (S500).

In step S100, the first light source 130 of the inspection device 10 may irradiate ultraviolet light toward the coating film of the substrate 2 on which the fluorescent dye is mixed. In step S200, the first photodetector 140 of the inspection device 10 may capture fluorescence generated from the coating film irradiated with ultraviolet light to obtain a two-dimensional image of the substrate. In operation S300, the processor 110 of the inspection device 10 may derive one region among a plurality of regions of the substrate based on the two-dimensional image. In step S400, the second light source 150 irradiates the laser light toward the derived one area, and the second light sensor 160 generates optical interference data (eg, first optical interference) generated from one area by the laser light. Data, etc.). Here, the optical interference data may be based on the interference light of the reference light and the measurement light formed by the first OCT part, or the reflected light (the reference light role) and the scattered light (measurement light role) formed by the second OCT part. In step S500, the processor 110 may derive the thickness of the coating film applied to one region of the substrate 2 based on the optical interference data. In the present disclosure, the application amount can be derived based on a two-dimensional image according to various embodiments. In addition, the thickness may be measured using the OCT part 170 according to various embodiments.

In one embodiment, deriving an area (S300), the processor 110 derives a coating amount of each of the plurality of areas based on the two-dimensional image of the substrate 2 and/or a plurality of areas It may include the step of determining the region of the coating amount is less than the predetermined amount of the above-described one region.

In one embodiment, deriving an area (S300) may include the processor 110 determining the above-described one area based on information on a region of interest preset by the user.

In one embodiment, the region of interest may be a region including electrodes of elements on a substrate.

In one embodiment, the step of deriving an area (S300) may include determining, by the processor 110, an area determined to be defective in the substrate as the one area described above based on the two-dimensional image.

In one embodiment, the region including the electrode may be derived by the processor 110 based on the device arrangement information indicating the arrangement of devices on the substrate.

In one embodiment, the reflected light reflected from the surface of the coating film may be used as reference light. In one embodiment, the second light source 150 according to the second OCT part may irradiate laser light toward the coating film of the substrate 2 along the first direction. Also, the second optical sensor 160 according to the second OCT part may capture interference light traveling in a reverse direction in the first direction.

In one embodiment, the interfering light may be interfering light generated by the reflected light reflected from the surface of the coating film and the scattered light scattered from the interface between the coating film and the substrate through the coating film. The interference light may be interference light generated from the above-described one region derived from a plurality of regions.

In one embodiment, the step (S500) of deriving the thickness of the coating film of a region is based on the optical interference data (for example, the first optical interference data, etc.) described above by the processor 110 in the depth direction of the coating film. Obtaining a cross-sectional image representing a cross-section in a corresponding first axis (eg, z-axis) direction and/or determining a thickness for the coating film applied to one area described above based on a boundary line on the cross-sectional image It may include.

Various embodiments of the present disclosure may be implemented in software in a machine-readable storage medium. The software can be software for implementing various embodiments of the present disclosure. Software may be deduced from various embodiments of the present disclosure by programmers in the art to which this disclosure pertains. For example, the software may be a program that includes instructions that can be read by a device (eg, code or code segment). The device is a device operable according to instructions called from a storage medium, and may be, for example, a computer. In one embodiment, the device may be an inspection device 10 according to embodiments of the present disclosure. In one embodiment, the processor of the device may execute the called command, so that the components of the device perform a function corresponding to the command. In one embodiment, the processor may be the processor 110 according to embodiments of the present disclosure. A storage medium can mean any kind of recording medium in which data is stored, which can be read by a device. The storage medium may include, for example, ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage, and the like. In one embodiment, the storage medium may be memory 120. In one embodiment, the storage medium may be implemented as a distributed form such as a networked computer system. The software may be distributed and stored in a computer system or the like and executed. The storage medium may be a non-transitory storage medium. A non-transitory storage medium refers to a tangible medium irrespective of whether data is stored semi-permanently or temporarily, and does not include a signal propagated in transitory.

Although the technical spirit of the present disclosure has been described by various embodiments above, the technical spirit of the present disclosure makes various substitutions, modifications, and changes that can be made within a range understood by those skilled in the art to which this disclosure belongs. Includes. It should also be understood that such substitutions, modifications and variations can be included within the scope of the appended claims.

Claims (22)

A first light source irradiating ultraviolet light toward the coating film of the substrate on which the fluorescent dye is mixed;
A first optical sensor that captures fluorescence generated from the coating film irradiated with the ultraviolet light to obtain a two-dimensional image of the substrate;
A memory for storing information indicating a region of interest on the predetermined substrate;
A processor for deriving a first region among a plurality of regions of the substrate based on the information indicating the region of interest and the two-dimensional image;
A second light source that irradiates laser light toward the first region; And
And a second optical sensor that acquires optical interference data generated from the first region by the laser light,
The processor derives a thickness of the coating film for the first region based on the optical interference data,
The region of interest is a region including electrodes of elements on the substrate.
According to claim 1,
The processor derives a coating amount of each of the plurality of regions based on the two-dimensional image, and determines a region of the plurality of regions having an application amount equal to or less than a predetermined amount as a second region,
The second light source irradiates laser light toward the second region, the second optical sensor acquires optical interference data generated from the second region, and the processor is configured to acquire optical interference data from the second region. A substrate inspection apparatus for deriving a thickness of a coating film for the second region based on the basis.
delete delete According to claim 1,
The processor determines, based on the two-dimensional image, a region determined to be defective in the substrate as a third region,
The second light source irradiates laser light toward the third area, the second light sensor acquires optical interference data generated from the third area, and the processor is configured to acquire optical interference data from the third area. A substrate inspection apparatus for deriving a thickness of a coating film for the third region based on the result.
According to claim 1,
The memory further stores device arrangement information indicating the arrangement of the devices on the substrate,
The processor compares the device arrangement information and the two-dimensional image to derive a fourth area including the electrode among the plurality of areas,
The second light source irradiates laser light toward the fourth region, the second optical sensor acquires optical interference data generated from the fourth region, and the processor is configured to acquire optical interference data from the fourth region. A substrate inspection apparatus for deriving a thickness of a coating film for the fourth region based on the result.
According to claim 1,
The reflected light reflected from the surface of the coating film is used as a reference light, the substrate inspection device.
The method of claim 7,
The processor,
Based on the optical interference data from the first region, a cross-sectional image showing a cross section in a first axial direction corresponding to a depth direction of the coating film is obtained,
And determining the thickness of the coating film for the first region based on the boundary line on the cross-sectional image.
The method of claim 7,
The reflectance of the surface of the coating film to the laser light is determined by the fluorescent dye mixing rate of the coating film in which the fluorescent dye is mixed,
The fluorescent dye mixing rate is set to a value such that the reflectance exceeds a preset reference value, the substrate inspection apparatus.
The method of claim 7,
The coating film is formed of at least one material selected from acrylic, urethane, polyurethane, silicone, epoxy, UV (Ultra Violet) curing material and IR (Infra Red) curing material, a substrate inspection device.
The method of claim 7,
The surface of the coating film is formed of a curved surface, the substrate inspection apparatus.
Irradiating ultraviolet light toward the coating film of the substrate on which the fluorescent dye is mixed;
Capturing fluorescence generated from the UV-irradiated coating film to obtain a two-dimensional image of the substrate;
Deriving a first region of the plurality of regions of the substrate based on the information indicating the region of interest on the predetermined substrate and the two-dimensional image;
Irradiating laser light toward the first area and obtaining light interference data generated from the first area by the laser light; And
Deriving a thickness of the coating film for the first region based on the optical interference data,
The region of interest is a region including electrodes of elements on the substrate, the method of inspecting a substrate.
The method of claim 12,
Deriving an application amount of a coating film for each of the plurality of regions based on the two-dimensional image;
Determining an area of the plurality of areas having an application amount equal to or less than a predetermined amount as a second area;
Irradiating laser light toward the second area to obtain light interference data generated from the second area; And
And deriving the thickness of the coating film for the second region based on the optical interference data from the second region.
delete delete The method of claim 12,
Determining, as a third region, a region determined to be defective in the substrate based on the two-dimensional image;
Irradiating laser light toward the third area to obtain light interference data generated from the third area; And
And deriving a thickness of the coating film for the third region based on the optical interference data from the third region.
The method of claim 12,
Comparing the device arrangement information indicating the arrangement of the devices on the substrate with the two-dimensional image, and deriving a fourth area including the electrode among the plurality of areas;
Irradiating laser light toward the fourth area to obtain light interference data generated from the fourth area; And
And deriving a thickness of the coating film for the fourth region based on the optical interference data from the fourth region.
The method of claim 12,
The reflected light reflected from the surface of the coating film is used as a reference light, the substrate inspection method.
The method of claim 18,
Obtaining a cross-sectional image showing a cross section in a first axial direction corresponding to a depth direction of the coating film, based on light interference data from the first area; And
And determining the thickness of the coating film for the first region based on the boundary line on the cross-sectional image.
The method of claim 18,
The reflectance of the surface of the coating film to the laser light is determined by the fluorescent dye mixing rate of the coating film in which the fluorescent dye is mixed,
The fluorescent dye mixing rate is set to a value such that the reflectance exceeds a preset reference value, the substrate inspection method.
The method of claim 18,
The coating film is formed of at least one material selected from acrylic, urethane, polyurethane, silicone, epoxy, UV (Ultra Violet) curing material and IR (Infra Red) curing material, the substrate inspection method.
The method of claim 18,
The surface of the coating film is formed of a curved surface, the substrate inspection method.

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