TWI716032B - Substrate inspection device, substrate processing apparatus, substrate inspection method and substrate processing method - Google Patents

Abstract

In the present invention, the data acquisition unit acquires the actual image data that displays at least a part of the image of the substrate of the inspection target having a circular outer periphery as the actual image. Based on the acquired actual image data, the shape of the substrate in the actual image is specified by the shape specifying part. The parameter calculation unit regards the substrate shape in the specified actual image as an elliptical shape, and calculates a correction parameter for correcting the actual image data based on the major axis and the minor axis of the elliptical shape. Based on the calculated correction parameters, the acquired actual image data is corrected by the data correction unit as the correction image data in such a way that the long diameter and the short diameter of the substrate shape in the actual image become equal. Based on the corrected image data, the substrate is inspected by the inspection section.

Description

Substrate inspection device, substrate processing device, substrate inspection method, and substrate processing method

The present invention relates to a substrate inspection device, a substrate processing device, a substrate inspection method, and a substrate processing method for performing substrate inspection.

Perform substrate inspection in various processing steps of substrate. For example, in the substrate inspection apparatus described in Patent Document 1, a band-shaped light with a larger diameter than the substrate is emitted downward from the light projecting part in one direction. In this state, the substrate of the inspection object moves in the other direction orthogonal to one direction by passing under the light projection part. Thereby, the strip light is irradiated to each part of the substrate in sequence. After that, the strip light is sequentially reflected by each part of the substrate and received by the light receiving part. Based on the amount of light received by the light-receiving part, image data showing the image of the entire surface of the substrate are generated. Based on the generated image data, the substrate is inspected.

[Patent Document 1] Japanese Patent Application Publication No. 2018-36235

[The problem to be solved by the invention]

In Patent Document 1, when the pixel size of the light-receiving part corresponding to the moving direction of the substrate is consistent with the moving pitch of the substrate, image data showing the substrate image with the correct aspect ratio is generated. However, in fact, it is difficult to make the pixel size consistent with the moving pitch of the substrate due to the mounting accuracy of the substrate moving mechanism. Therefore, the image data for displaying the substrate image with the correct aspect ratio is not generated. When the substrate has a perfect circular shape, the substrate image displayed by the image data also has an elliptical shape. In this case, the accuracy of substrate inspection based on image data is reduced.

The object of the present invention is to provide a substrate inspection device, a substrate processing device, a substrate inspection method, and a substrate processing method that can inspect a substrate with higher accuracy based on image data. [Technical means to solve the problem]

(1) A substrate inspection apparatus according to one aspect of the present invention includes: a substrate holding portion that holds at least a part of a substrate to be inspected having a circular outer periphery; and a data acquisition portion that acquires information about the substrate to be held by the substrate holding portion The actual image data displayed as the actual image; the shape specifying section, which specifies the substrate shape in the actual image based on the actual image data obtained by the data obtaining section; the parameter calculation section, which is determined by the shape specifying section The shape of the substrate in the specified actual image is regarded as an elliptical shape, and the correction parameters used to correct the actual image data based on the major and minor diameters of the ellipse are calculated; the data correction part is based on the calculation by the parameter calculation part The correction parameter is to correct the actual image data obtained by the data acquisition unit as the corrected image data in such a way that the long diameter and the short diameter of the substrate shape in the actual image become equal; and the inspection unit based on the data correction unit Correct the image data and check the substrate.

In this substrate inspection apparatus, at least a part of a substrate to be inspected having a circular outer periphery is held by the substrate holding portion. Obtain actual image data that displays the substrate image held by the substrate holding portion as the actual image. Based on the actual image data obtained, the outline of the substrate in the actual image is specified. The shape of the substrate in the specified actual image is regarded as an elliptical shape, and a correction parameter for correcting the actual image data based on the major axis and the minor axis of the elliptical shape is calculated. Based on the calculated correction parameters, the obtained actual image data is used as the corrected image data to be corrected in such a way that the long diameter and the short diameter of the substrate shape in the actual image become equal. Check the substrate based on the corrected image data.

According to this configuration, when the substrate is deformed into an elliptical shape in the actual image, the actual image data is corrected by using the correction parameters based on the major axis and the minor axis of the elliptical shape to generate corrected image data. In the corrected image based on the corrected image data, a substantially round substrate is displayed. Thereby, the substrate can be inspected with higher accuracy based on the corrected image data. In addition, it is not necessary to separately prepare a special substrate or jig for calculating the correction parameters, and it is not necessary to set the correction parameters in advance. Therefore, the time and cost required for the generation of the corrected image data can be reduced.

(2) It is also possible that the substrate of the inspection object has a non-circular part to indicate the direction of the substrate. The shape specifying part excludes the actual image data of the part of the substrate corresponding to the non-circular part, and specifies the actual image The shape of the substrate in the image. According to this configuration, even when the substrate of the inspection object has a non-circular portion, it is easy to regard the outline of the substrate in the actual image as an elliptical shape. In this way, the correction parameters can be easily calculated.

(3) The substrate holding part may also hold the substrate in such a way that the non-circular part of the substrate faces a predetermined direction, and the data acquisition part obtains actual image data indicating the actual image of the substrate in the state where the non-circular part faces the predetermined direction . In this case, it is easy to exclude the actual image data of the portion of the substrate corresponding to the non-circular portion, and specify the shape of the substrate in the actual image.

(4) The parameter calculation unit may also calculate the correction parameter by performing multiple regression analysis using the substrate shape specified by the shape specifying portion and the equation representing the ellipse. According to this configuration, even when the substrate in the actual image is deformed, the correction parameters can be calculated with higher accuracy.

(5) It may also be that the shape specifying part specifies the shape of the substrate in the actual image by filtering the actual image data obtained by the data obtaining part. In this case, the outline of the substrate in the actual image can be easily specified.

(6) The substrate inspection device may also be provided with: an imaging section that uses a line sensor extending in the first direction to photograph the substrate held by the substrate holding section to generate actual image data; and a moving section that uses the substrate The substrate held by the holding part moves relative to the imaging part in a second direction intersecting the first direction to move at least one of the substrate holding part and the imaging part; and the data acquisition part obtains the actual image produced by the imaging part data.

In this case, by using the moving part to move at least one of the substrate holding part and the imaging part in the second direction at a specific pitch, actual image data can be easily generated. Here, when the pixel size of the line sensor in the direction corresponding to the second direction is inconsistent with the above-mentioned moving pitch, the substrate in the actual image is transformed into an elliptical shape. In this case, in the corrected image based on the corrected image data, a substantially circular substrate is also displayed. Thereby, the substrate can be inspected with higher accuracy based on the corrected image data.

(7) A substrate processing apparatus according to another aspect of the present invention is provided with: a film forming section that forms a processing film on a substrate; and a substrate inspection apparatus according to one aspect of the present invention, which forms a processing film from the film forming section Substrate inspection afterwards.

In this substrate processing apparatus, the substrate after the processing film is formed by the film forming section is inspected by the above-mentioned substrate inspection apparatus. Thereby, the substrate can be inspected with higher accuracy based on the corrected image data. In addition, it is not necessary to separately prepare a special substrate or jig for calculating the correction parameters, and it is not necessary to set the correction parameters in advance. Therefore, the time and cost required for the generation of the corrected image data can be reduced.

(8) A substrate inspection method according to another aspect of the present invention includes a step of holding by a substrate holding portion at least a part of a substrate to be inspected having a circular outer periphery; obtaining an image of the substrate held by the substrate holding portion as The step of displaying the actual image data of the actual image; the step of specifying the outline of the substrate in the actual image based on the obtained actual image data; the outline of the substrate in the specified actual image is regarded as an elliptical shape, and the calculation is used The step of correcting the correction parameters of the actual image data based on the major and minor diameters of the ellipse; based on the calculated correction parameters, the major and minor diameters of the substrate shape in the actual image will be obtained. The actual image data is used as the correction image data to be corrected; and the step of inspecting the substrate based on the corrected correction image data.

According to this substrate inspection method, when the substrate in the actual image is deformed into an elliptical shape, the substrate can also be inspected with higher accuracy based on the corrected image data. In addition, it is not necessary to separately prepare a special substrate or jig for calculating the correction parameters, and it is not necessary to set the correction parameters in advance. Therefore, the time and cost required for the generation of the corrected image data can be reduced.

(9) The substrate that can also be the inspection object has a non-circular part to indicate the direction of the substrate, and the step of identifying the shape of the substrate in the actual image includes the step of matching the part of the substrate to the non-circular part. Except the actual image data, and specify the shape of the substrate in the actual image. According to this configuration, when the substrate of the inspection object has a non-circular shape part, it is easy to regard the outer shape of the substrate in the actual image as an elliptical shape. In this way, the correction parameters can be easily calculated.

(10) The step of holding the substrate of the inspection object by the substrate holding portion may include: holding the substrate by the substrate holding portion so that the non-circular portion of the substrate faces a predetermined direction; specifying the shape of the substrate in the actual image includes : By obtaining the actual image data of the actual image of the substrate showing the non-circular part facing the predetermined direction, the actual image data of the part of the substrate corresponding to the non-circular part is excluded, and the actual image is specified The shape of the substrate. In this case, it is easy to exclude the actual image data of the portion corresponding to the non-circular portion of the substrate, and specify the shape of the substrate in the actual image.

(11) The step of calculating the correction parameters may also include: calculating the correction parameters by performing multiple regression analysis using a specific substrate shape and an equation representing an ellipse. According to this structure, even when the substrate of the actual image is deformed, the correction parameters can be calculated with higher accuracy.

(12) The step of specifying the shape of the substrate in the actual image may also include: specifying the shape of the substrate in the actual image by filtering the acquired actual image data. In this case, the outline of the substrate in the actual image can be easily specified.

(13) The substrate inspection method may further include: moving the substrate relative to the imaging section including the line sensor extending in the first direction in a second direction intersecting the first direction, and the moving section causes The step of moving at least one of the substrate holding part and the imaging part; and the step of generating actual image data by photographing the substrate held by the substrate holding part by the imaging part; and the step of obtaining the actual image data includes obtaining the actual image data generated by the imaging part The actual image data.

In this case, by using the moving part to move at least one of the substrate holding part and the imaging part in the second direction at a specific pitch, actual image data can be easily generated. Here, when the pixel size of the line sensor in the direction corresponding to the second direction does not match the above-mentioned moving pitch, the substrate in the actual image is deformed into an elliptical shape. In this case, in the corrected image based on the corrected image data, a substantially circular substrate is also displayed. Thereby, the substrate can be inspected with higher accuracy based on the corrected image data.

(14) Still another aspect of the substrate processing method of the present invention includes: forming a processing film on the substrate by the film forming portion; and forming the processing film on the film forming portion by the substrate inspection method of the other aspect of the present invention Then the substrate is inspected.

According to this substrate processing method, the substrate after the processing film is formed by the film forming portion is inspected by the above-mentioned substrate inspection method. Thereby, the substrate can be inspected with higher accuracy based on the corrected image data. In addition, it is not necessary to separately prepare a special substrate or jig for calculating the correction parameters, and it is not necessary to set the correction parameters in advance. Therefore, the time and cost required for the generation of the corrected image data can be reduced. [Effects of Invention]

According to the present invention, the substrate can be inspected with higher accuracy based on image data.

Hereinafter, the substrate inspection apparatus, the substrate processing apparatus, the substrate inspection method, and the substrate processing method according to the embodiments of the present invention will be described using drawings. In the following description, the substrate means a semiconductor substrate, a liquid crystal display device, or an organic EL (Electro Luminescence: electroluminescence) display device, such as FPD (Flat Panel Display) substrate, optical disk substrate, magnetic disk substrate, Substrates for magneto-optical discs, substrates for photomasks, ceramic substrates, substrates for solar cells, etc.

The substrate used in this embodiment has at least a part of a circular outer periphery. Specifically, an orientation plane for positioning is formed on the substrate, and the peripheral portion has a circular shape except for the orientation plane of the substrate. The diameter of the circular part of the substrate is, for example, 200 mm in diameter. On the substrate, grooves can also be formed to replace the orientation plane.

(1) Composition of substrate inspection device Fig. 1 is a perspective view of the appearance of a substrate inspection apparatus according to an embodiment of the present invention. FIG. 2 is a schematic side view showing the internal structure of the substrate inspection apparatus 200 of FIG. 1. As shown in FIG. 1, the substrate inspection apparatus 200 includes a housing part 210, a light projecting part 220, a reflecting part 230, an imaging part 240, a substrate holding device 250, a moving part 260, a direction detecting part 270 and a control part 280.

The light projecting unit 220, the reflecting unit 230, the imaging unit 240, the substrate holding device 250, the moving unit 260, and the direction detecting unit 270 are housed in the housing unit 210. The control unit 280 includes, for example, a CPU (central processing unit), a memory, or a microcomputer, and controls the operations of the light projecting unit 220, the imaging unit 240, the substrate holding device 250, the moving unit 260, and the direction detecting unit 270.

The light projecting unit 220 includes, for example, one or a plurality of light sources, and emits band-shaped light with a larger diameter than the substrate W obliquely downward. The light from the light projection part 220 has a long horizontal cross section extending in the X direction. The reflection part 230 includes, for example, a mirror surface. The imaging unit 240 includes imaging elements such as a line sensor 241 arranged in such a way that a plurality of pixels are arranged linearly in the X direction, and one or more condensing lenses. In this example, a CCD (Charge Coupled Device) line sensor is used as the imaging element. In addition, a COMS (Complementary Metal Oxide Semiconductor) line sensor can also be used as an imaging element.

As shown in FIG. 2, the substrate holding device 250 is, for example, a rotating chuck, and includes a driving device 251 and a rotating holding portion 252. The driving device 251 is, for example, an electric motor, and has a rotating shaft 253. The rotation holding part 252 is installed at the front end of the rotation shaft 253 of the driving device 251 to rotate and drive around the vertical axis while holding the substrate W of the inspection object.

The moving part 260 includes a pair of rail members 261 and a moving holding part 262. The pair of rail members 261 are provided to extend in the Y direction parallel to each other. The Y direction is orthogonal to the X direction on the horizontal plane. The moving holding portion 262 is configured to hold the substrate holding device 250 and move in the Y direction along the pair of rail members 261. By moving the moving holding portion 262 in the Y direction in a state where the substrate W is held by the substrate holding device 250, the substrate W passes under the light projecting portion 220 and the reflecting portion 230.

The direction detecting unit 270 is a reflective photodetector including, for example, a light emitting element and a light receiving element. When the substrate W of the inspection object is rotated by the substrate holding device 250, it emits light toward the outer periphery of the substrate W and receives light from the substrate. The reflected light of W. The direction detecting unit 270 detects the orientation plane of the substrate W based on the amount of light received by the reflected light from the substrate W. A transmissive photoelectric sensor may also be used as the direction detection unit 270.

The imaging operation of the substrate W of the substrate inspection apparatus 200 of FIG. 1 will be described. On the side of the frame body 210, a slit-shaped opening 211 for conveying the substrate W is formed. The substrate W to be inspected is carried into the frame portion 210 through the opening 211 by the transfer device 120 of FIG. 9 described later, and is held by the substrate holding device 250.

Then, the substrate W is rotated by the substrate holding device 250, and the direction detecting portion 270 emits light to the periphery of the substrate W, and the direction detecting portion 270 receives the reflected light. Thereby, the orientation plane of the substrate W is detected, and the direction of the substrate W is determined. Based on the determination result, the substrate holding device 250 adjusts the rotation position of the substrate W such that the orientation plane of the substrate W faces a specific direction (in this example, one of the Y directions).

Then, the strip-shaped light is emitted diagonally downward from the light projection part 220, and the moving part 260 moves the substrate W in one direction so as to pass under the light projection part 220. Thereby, the light from the light projecting part 220 is irradiated to the entire one surface of the substrate W. The light reflected by one surface of the substrate W is further reflected by the reflection part 230 and guided to the imaging part 240.

The imaging element of the imaging unit 240 receives the light reflected by one surface of the substrate W in a specific sampling period, and sequentially images one surface of the substrate W. Each pixel constituting the imaging element outputs pixel data showing a value corresponding to the amount of light received. Based on the plurality of pixel data output from the imaging unit 240, actual image data of the entire image on one surface of the display substrate W is generated. Thereafter, the substrate W is returned to a specific position by the moving part 260, and the substrate W is carried out to the outside of the frame body part 210 through the opening part 211 by the conveying device 120 of FIG. 9 described later.

(2) Function of substrate inspection device FIG. 3 is a diagram showing an example of an actual image of the substrate W displayed using actual image data generated by the imaging unit 240 of FIG. 1. The position of each pixel of the actual image data is represented by the device-specific two-dimensional coordinate system (hereinafter referred to as the device coordinate system). In this embodiment, the device coordinate system is an xy coordinate system having x-axis and y-axis orthogonal to each other. The positive direction in the x direction is right, and the positive direction in the y direction is up. The origin of the device coordinate system is set to, for example, a pixel located in the center of the actual image RI.

The x direction and the y direction correspond to the X direction and the Y direction in Figure 1 respectively. As described above, in this example, the substrate W is captured by the imaging unit 240 with the orientation plane OF facing one of the Y directions. Thereby, as shown in FIG. 3, actual image data showing the actual image of the substrate W with the orientation plane OF facing downward in the y direction are generated.

In the y direction, the pixel size of the imaging element of the imaging section 240 and the movement pitch of the substrate W in the Y direction of the moving section 260 of FIG. 1 are consistent, resulting in an actual image showing the actual image of the substrate W with the correct aspect ratio Like information. In addition, the aspect ratio means the ratio of the size in the x direction to the size in the y direction. However, in reality, it is difficult to make the pixel size match the moving pitch of the substrate W due to the mounting accuracy of the component parts of the moving part 260 and other reasons. Therefore, in the case where the outer periphery of the substrate W except for the orientation plane OF has a circular shape, as shown in FIG. 3, the actual image of the substrate W displayed by the generated actual image data has a substantially elliptical shape. In this case, the inspection accuracy of the substrate W based on actual image data is reduced.

In addition, in this embodiment, the orientation flat OF is formed on the substrate W, and the aspect ratio of the substrate W is not 1:1. Therefore, only stretching the actual image in the vertical or horizontal direction with the aspect ratio of the substrate W in the actual image being 1:1, the image data of the correct image of the display substrate W cannot be generated. In addition, in this example, the diameter of the substrate is 200 mm, which is relatively small. In this case, the substrate displayed by the stretched image is even more incorrect. Therefore, the substrate inspection apparatus 200 performs the following correction processing on the actual image data to generate corrected image data that displays the correct image of the substrate W as the corrected image.

FIG. 4 is a block diagram showing the functional configuration of the substrate inspection apparatus 200. As shown in FIG. 4, the board inspection apparatus 200 includes a data acquisition unit 1 as a functional unit, an external shape specifying unit 2, a parameter calculation unit 3, a data correction unit 4, and an inspection unit 5. The functional unit of the substrate inspection apparatus 200 is realized by, for example, the CPU of the control unit 280 executes a computer program stored in a memory. In addition, part or all of the functional parts of the substrate inspection apparatus 200 may also be realized by hardware such as electronic circuits.

The data acquisition unit 1 acquires the actual image data of the actual image of the substrate W in a state where the orientation plane OF is oriented in a specific direction from the imaging unit 240. The shape specifying unit 2 specifies the shape of the substrate W in the actual image based on the actual image data obtained by the data obtaining unit 1. The shape of the substrate W of the actual image is specified by excluding the actual image data of the portion corresponding to the orientation plane OF of the substrate W. In this example, since the orientation plane OF in the actual image faces a specific direction, it is easy to exclude the actual image data corresponding to the orientation plane OF, and specify the shape of the substrate W in the actual image.

The parameter calculation unit 3 regards the shape of the substrate W in the actual image specified by the shape specifying unit 2 as an elliptical shape, and calculates a correction parameter for correcting the actual image data based on the major axis and the minor axis of the elliptical shape. In addition, the oval shape includes a circular shape. Therefore, when the pixel size of the imaging element of the imaging section 240 in the y direction and the movement pitch of the substrate W in the Y direction of the moving section 260 of FIG. 1 are consistent, the outer shape of the substrate W is regarded as a circular shape.

The data correction unit 4 corrects the actual image data acquired by the data acquisition unit 1 by using the correction parameters calculated by the parameter calculation unit 3 so that the long and short diameters of the outer shape of the substrate W in the actual image become equal. And generate corrected image data.

The inspection unit 5 inspects the substrate W based on the corrected image data corrected by the data correction unit 4. In this example, the sample image data representing the image of the sample substrate without defects in appearance is used to determine whether the substrate W of the inspection object is defective. For example, a high-precision inspection is performed in advance, and a substrate determined to be non-defective during the inspection is used as a sample substrate. The sample image data can also be obtained from the inspection device 200, or from other devices. In addition, the pre-generated design data can also be used as sample image data.

(3) Inspection and treatment FIG. 5 is a flowchart showing the inspection process performed by the control unit 280 of FIG. 4. Hereinafter, the inspection process will be described using FIG. 4. First, the data acquisition unit 1 acquires actual image data from the imaging unit 240 (step S1). Next, the external shape specifying unit 2 specifies the external shape of the substrate W of the actual image obtained in step S1 (step S2).

Then, the parameter calculation unit 3 regards the outer shape of the substrate W specified in step S2 as an elliptical shape, and calculates a correction parameter based on the major diameter and the minor diameter of the elliptical shape (step S3). After that, the data correcting unit 4 corrects the actual image data obtained in step S1 in such a way that the long and short diameters of the outer shape of the substrate W in the actual image become equal by the correction parameters calculated based on step S3, and The corrected image data is generated (step S4).

Next, the inspection unit 5 compares the sample image data with the corrected image data generated in step S4 (step S5). In addition, the inspection section 5 may also store sample image data in advance, or may be obtained by a memory device not shown. Then, the inspection unit 5 determines whether the deviation of the values of all pixels between the sample image data and the corrected image data is below a specific threshold value (step S6).

When the values of all pixels deviate below the threshold value, the inspection section 5 determines that the substrate W shown in the corrected image is normal (step S7), and proceeds to step S9. On the other hand, when the deviation of the value of any pixel exceeds the threshold value, the inspection unit 5 determines that the substrate W shown in the corrected image is abnormal (step S8), and proceeds to step S9.

In step S9, the inspection unit 5 determines whether all the substrates W have been inspected (step S9). If all the substrates W have not been inspected, the inspection unit 5 returns to step S1 and repeats steps S1 to S9 until all the substrates W have been inspected. If all the substrates W have been inspected, the inspection unit 5 ends the inspection process.

6 to 8 are diagrams for conceptually explaining the generation sequence of corrected image data in the inspection process. In step S2 of the inspection process in FIG. 5, filtering processing such as Sobel filtering is performed on the actual image data. In this case, the absolute value of the pixel representing the actual image data on the outer periphery (edge portion) of the substrate W becomes larger. Also, as shown in FIG. 6, a plurality of imaginary lines L1 to L8 extending outward from the origin O of the device coordinate system (8 in this example) are set. For example, the virtual lines L1 to L8 are arranged at equal angular intervals (45-degree intervals) with respect to the origin O.

For each of the imaginary lines L1 to L8, from the outside toward the origin O, the position coordinates of the pixels whose absolute value becomes the specified threshold value or more for the first time are detected. In the example of FIG. 6, the coordinates of positions A1 to A8 are detected on the imaginary lines L1 to L8, respectively. In addition, the coordinates of the positions A1 to A8 are (x1, y1), (x2, y2), ... and (x8, y8), respectively. By detecting the coordinates of the positions A1 to A8 of the plurality of peripheral parts of the substrate W corresponding to the plurality of imaginary lines L1 to L8, respectively, the outer shape of the substrate W is specified.

In addition, in the above example, when the specific substrate W is out of shape, the eight imaginary lines L1 to L8 are arranged at an interval of 45 degrees, but the present invention is not limited to this. It can also be configured with less than 7 imaginary lines L1 to L8, and can also be configured with more than 9 imaginary lines. When a larger number of imaginary lines are arranged at a smaller angular interval, the outer shape of the substrate W can be specified with higher accuracy.

The shape of the substrate W thus specified is regarded as an elliptical shape by the parameter calculation unit 3, and the following step S3 is executed. In addition, as described above, in the actual image, the orientation plane OF of the substrate W faces downward. Therefore, the position A5 detected on the imaginary line L5 extending downward from the origin corresponds to the position of the orientation plane OF of the substrate W. Therefore, in this example, in addition to the position A5, by detecting the positions A1 to A4 and A6 to A8, the shape of the substrate W is specified. Thereby, it is easy to regard the outer shape of the substrate W in the actual image as an elliptical shape.

In step S3 of the inspection process of FIG. 5, the correction parameters are calculated by performing multiple regression analysis using the elliptical shape of the substrate W specified in step S2 and the equation showing the ellipse. Specifically, the equation showing the ellipse is represented by the following equation (1). In formula (1), x and y are the coordinates in the x direction and y direction in the device coordinate system, respectively. a and b are the long and short diameters of the ellipse respectively. O _x and O _y are the x-direction and y-direction coordinates of the center of the ellipse, respectively.

[Number 1]

In the example of FIG. 7, the long diameter a is the long radius along the x direction, and the short diameter b is the short radius along the y direction. In addition, the long diameter a may be the short radius along the x direction, and the short diameter b may be the long radius along the y direction. Furthermore, in the example of FIG. 7, the center coordinates (O _x , O _y ) of the ellipse are located at the origin of the device coordinate system, or may not be located at the origin of the device coordinate system.

Then, as shown in the following formula (2), if the magnification of the short axis b with respect to the long axis a is k, the formula (1) changes to the polynomial shown in the following formula (3). In the formula (3), the coefficients K ₁ , K ₂ , K ₃ and K ₄ are represented by the following formulas (4), (5), (6) and (7), respectively.

[Number 2]

[Number 3]

[Number 4]

[Number 5]

[Number 6]

[Number 7]

Then, the coordinates (x1, y1), (x2, y2), ... and (x8, y8) of the positions A1 to A4, A6 to A8 detected in step S2 are applied to the (x, y) of formula (3) ). Furthermore, by setting x ² as the target variable and x, y ² and y as the explanatory variables, a multiple regression analysis is performed to obtain the coefficients K ₁ to K _{4 in} equations (4) to (7). According to this method, when the substrate W in the actual image is deformed, the coefficients K ₁ to K ₄ can be calculated with higher accuracy. Based on the coefficients K ₁ to K ₄ , the major axis a of the ellipse is obtained by the following formula (8). The short diameter b of the ellipse is obtained by formula (2). In addition, the magnification k is obtained by the following formula (9).

[Number 8]

[Number 9]

After that, the calculated magnification k is set as a correction parameter, and the actual image data is corrected so that the major axis a and the minor axis b are equal. As a result, the corrected image data showing the corrected image CI is generated as shown in FIG. 8. In addition, in the example of FIG. 8, the actual image data is corrected so that the short axis b in the y direction is equal to the long axis a, and the actual image data can also be corrected so that the long axis a and the short axis b in the x direction are equal .

(4) Substrate processing equipment FIG. 9 is a schematic block diagram showing the overall structure of a substrate processing apparatus equipped with the substrate inspection apparatus 200 of FIGS. 1 and 2. As shown in FIG. 9, the substrate processing apparatus 100 is provided adjacent to the exposure apparatus 300, and includes a substrate inspection apparatus 200, and also includes a control device 110, a conveying device 120, a film forming unit 130, a developing unit 140, and a heat treatment unit 150.

The control device 110 includes, for example, a CPU and a memory, or a microcomputer, and controls the operations of the conveying device 120, the film forming unit 130, the developing unit 140, and the heat treatment unit 150. In addition, the control device 110 gives a command for inspecting the substrate W to the control unit 280 of FIG. 1 of the substrate inspection device 200.

The transport device 120 transports the substrate W between the film forming unit 130, the developing unit 140, the heat treatment unit 150, the substrate inspection device 200, and the exposure device 300. The film forming section 130 forms a resist film on the surface of the substrate W by coating the surface of the substrate W with a resist solution (film formation process). The substrate W after the film formation process is exposed to the exposure device 300. The developing unit 140 performs development processing of the substrate W by supplying a developing solution to the substrate W after exposure processing by the exposure device 300. The heat treatment part 150 performs heat treatment of the substrate W before and after the film formation process of the film formation part 130, the development process of the developing part 140, and the exposure process of the exposure device 300.

The substrate inspection apparatus 200 performs inspection processing of the substrate W after the resist film is formed by the film forming section 130. For example, the substrate inspection apparatus 200 performs the inspection of the substrate W after the film formation process in the film formation section 130 and the development process in the development section 140. Or, the substrate inspection apparatus 200 may also perform the inspection of the substrate W after the film formation process of the film forming part 130 and before the exposure process of the exposure apparatus 300. In addition, the substrate inspection apparatus 200 can also perform inspection of the substrate W after the film formation process of the film forming section 130, after the exposure process of the exposure apparatus 300, and before the development process of the developing section 140.

A processing unit for forming an anti-reflection film on the substrate W may also be provided in the film forming part 130. At this time, the heat treatment unit 150 may also perform an adhesion strengthening treatment for improving the adhesion between the substrate W and the anti-reflection film. In addition, a processing unit may be provided in the film forming portion 130 to form a resist protection film for protecting the resist film formed on the substrate W.

When the anti-reflection film and the anti-corrosion protective film are formed on one surface of the substrate W, the substrate W may be inspected by the substrate inspection apparatus 200 after the formation of each film. In the substrate processing apparatus 100 of this embodiment, the substrate W on which a film such as a resist film, an anti-reflection film, or a resist protection film is formed is inspected with high reliability by the substrate inspection apparatus 200.

In this example, the substrate processing apparatus 100 that processes the substrate W before and after exposure is provided with the substrate inspection apparatus 200, but the substrate inspection apparatus 200 may be provided in other substrate processing apparatuses. For example, the substrate inspection device 200 may be installed in a substrate processing device that performs cleaning processing on the substrate W, or the substrate inspection device 200 may be installed in a substrate processing device that performs etching processing of the substrate W. Or, the substrate inspection device 200 may be used alone.

(5) Effect In the substrate processing apparatus 100 of this embodiment, the substrate W is held by the substrate holding device 250, and the substrate holding device 250 is moved in the Y direction at a specific interval by the moving part 260, and the imaging part 240 is used to generate actual image data. Here, when the pixel size of the line sensor 241 in the y direction corresponding to the Y direction is inconsistent with the moving pitch of the substrate holding device 250, the substrate W in the actual image RI is deformed into an elliptical shape.

In this case, in the substrate inspection apparatus 200, the actual image data may also be acquired by the data acquisition unit 1. Based on the acquired actual image data, the outer shape of the substrate W in the actual image RI is specified by the shape specifying section 2. The parameter calculation unit 3 regards the outer shape of the substrate W in the actual image RI specified as an elliptical shape, and calculates the correction parameter based on the major diameter and the minor diameter of the elliptical shape. The image data is used as the corrected image data to be corrected by the data correction unit 4 in such a way that the long diameter and the short diameter of the outer shape of the substrate W in the actual image RI are equal based on the calculated correction parameters. Based on the corrected corrected image data, the substrate W is inspected by the inspection section 5.

According to this configuration, when the substrate W is deformed into an elliptical shape in the actual image RI, the actual image data is corrected by using the correction parameters based on the major axis and the minor axis of the elliptical shape to generate corrected image data. In the corrected image CI based on the corrected image data, the substrate W having a substantially perfect circular shape is displayed. Thereby, the substrate W can be inspected with higher accuracy based on the corrected image data. In addition, there is no need to prepare a special substrate or jig for calculating the correction parameters, and it is not necessary to set the correction parameters in advance. Therefore, the time and cost required for the generation of the corrected image data can be reduced.

(6) Other implementation forms (a) In the above embodiment, the substrate W on which the orientation plane OF for positioning is formed is inspected by the substrate inspection apparatus 200, but the present invention is not limited to this. It is also possible to inspect the substrate W formed with the groove for positioning instead of the orientation plane OF by the substrate inspection apparatus 200. Or, the substrate W can be inspected by the substrate inspection apparatus 200 without forming the orientation flat OF and the circular shape of the groove.

(b) In the above embodiment, the appearance inspection of the substrate W is performed as the inspection of the substrate W, but the present invention is not limited to this. Other inspections can also be performed as the inspection of the substrate W. For example, it is also possible to check whether the distance (edge width) between the outer circumference of the substrate W and the outer circumference of the film formed on the substrate W is appropriate based on the corrected image data. In this case, the edge width can be appropriately detected by using the corrected image data. Thereby, the accuracy of determining whether the edge width is appropriate can be improved.

(c) In the above embodiment, the substrate W is photographed by the imaging unit 240 in a state where the rotation position of the substrate W is adjusted so that the orientation plane OF faces a specific direction by the substrate holding device 250, but the present invention is not limited Here. It is also possible to image the substrate W by the imaging unit 240 in a state where the orientation plane OF faces any direction. In this case, the shape specifying section 2 performs image processing on the actual image data, excluding the actual image data of the portion corresponding to the orientation plane PF of the substrate W, and specifies the substrate W in the actual image. Outside shape.

(7) Correspondence between the constituent elements of the claim and the elements of the implementation form Hereinafter, examples of the correspondence between the constituent elements of the claim and the elements of the embodiment will be described, but the present invention is not limited to the following examples. As each constituent element of the claim, various other elements having the structure or function described in the claim may also be used.

In the above embodiment, the substrate W is an example of a substrate, the substrate holding device 250 is an example of a substrate holding portion, the actual image RI is an example of an actual image, and the data acquisition unit 1 is an example of a data acquisition unit. The shape specifying section 2 is an example of the shape specifying section, the parameter calculation section 3 is an example of a parameter calculation section, the corrected image CI is an example of a corrected image, the data correction section 4 is an example of a data correction section, and the inspection section 5 is an inspection section的例。 Examples.

The substrate inspection apparatus 200 is an example of a substrate inspection apparatus, the orientation plane OF is an example of a non-circular portion, and the X direction and the Y direction are examples of the first and second directions, respectively. The line sensor 241 is an example of a line sensor, the imaging section 240 is an example of an imaging section, the moving section 260 is an example of a moving section, the film forming section 130 is an example of a film forming section, and the substrate processing apparatus 100 is a substrate processing apparatus的例。 Examples.

1‧‧‧Data Acquisition Department 2‧‧‧Shape specific part 3‧‧‧Parameter calculation section 4‧‧‧Data Correction Department 5‧‧‧Inspection Department 100‧‧‧Substrate processing equipment 110‧‧‧Control device 120‧‧‧Conveying device 130‧‧‧Film forming part 140‧‧‧Development Department 150‧‧‧Heat Treatment Department 200‧‧‧Substrate inspection device 210‧‧‧Frame 211‧‧‧Opening 220‧‧‧Light Projection Department 230‧‧‧Light Projection Department 240‧‧‧Camera Department 241‧‧‧Line Sensor 250‧‧‧Substrate holding device 251‧‧‧Drive device 252‧‧‧Rotation holding part 253‧‧‧Rotation axis 260‧‧‧Mobile Department 261‧‧‧Guide member 262‧‧‧Mobile holding part 270‧‧‧Direction detection section 280‧‧‧Control Department 300‧‧‧Exposure device A1～A8‧‧‧Coordinates a‧‧‧Long Path b‧‧‧Short Path CI‧‧‧Correct image K1～K4‧‧‧Coefficient K‧‧‧Magnification L1～L8‧‧‧Imaginary line O‧‧‧origin OF‧‧‧Orientation plane PF‧‧‧Orientation plane RI‧‧‧Real image S1～S9‧‧‧Step W‧‧‧Substrate X‧‧‧direction x‧‧‧direction Y‧‧‧ direction y‧‧‧direction

Fig. 1 is a perspective view of the appearance of a substrate inspection apparatus according to an embodiment of the present invention. Fig. 2 is a schematic side view showing the internal structure of the substrate inspection device of Fig. 1. FIG. 3 is a diagram showing an example of an actual image of a substrate displayed using actual image data generated by the imaging unit of FIG. 1. FIG. Figure 4 is a block diagram showing the functional configuration of the substrate inspection device. Fig. 5 is a flowchart showing the inspection process performed by the control unit of Fig. 4; Fig. 6 is a diagram for conceptually explaining the generation sequence of corrected image data in the inspection process. FIG. 7 is a diagram for conceptually explaining the generation sequence of the corrected image data in the inspection process. FIG. 8 is a diagram for conceptually explaining the generation sequence of corrected image data in the inspection process. 9 is a schematic block diagram showing the overall structure of a substrate processing apparatus equipped with the substrate inspection apparatus of FIGS. 1 and 2.

1‧‧‧Data Acquisition Department

2‧‧‧Shape specific part

3‧‧‧Parameter calculation section

4‧‧‧Data Correction Department

5‧‧‧Inspection Department

200‧‧‧Substrate inspection device

240‧‧‧Camera Department

280‧‧‧Control Department

Claims (12)

A substrate inspection apparatus, comprising: a substrate holding portion that holds at least a part of a substrate to be inspected having a circular outer periphery; and a data acquisition portion that acquires an image of the substrate held by the substrate holding portion as an actual image The actual image data displayed; the shape specifying section, which specifies the substrate shape in the actual image based on the actual image data obtained by the above-mentioned data obtaining section; the parameter calculation section, which specifies the actual image specified by the above shape specifying section The shape of the substrate in the image is regarded as an elliptical shape, and the correction parameters used to correct the actual image data based on the major and minor diameters of the ellipse are calculated; the data correction part is based on the correction parameters calculated by the above-mentioned parameter calculation part to In the actual image, the long diameter and short diameter of the external shape of the substrate become equal, and the actual image data obtained by the data acquisition unit is corrected as the corrected image data; and the inspection unit is based on the correction by the data correction unit The image data is corrected to inspect the substrate; and the inspection target substrate has a non-circular portion to indicate the direction of the substrate; and the above-mentioned shape specifying part is set in the actual image data to extend from the preset origin to the outside A plurality of imaginary lines; for each of the plurality of imaginary lines, from the outside toward the origin, the position of the pixel whose absolute value first becomes above a certain threshold is detected from the outside; an imaginary extending from the origin to the non-circular shape part Position self-check Excluding the measured position; based on a plurality of positions other than the excluded position, specify the substrate shape of the actual image excluding the actual image data of the part of the substrate corresponding to the above non-circular shape part; and the above parameter calculation part is based on borrowing Calculate the major and minor diameters of the substrate profile of the elliptical shape in the actual image from the outer shape of the substrate specified by the outline specifying part and the equation representing the ellipse, and use the magnification of the major and minor diameters as the correction Parameters and calculated. The substrate inspection apparatus of claim 1, wherein the substrate holding portion holds the substrate in such a manner that the non-circular portion of the substrate faces a predetermined direction; and the data acquisition portion obtains and indicates that the non-circular portion faces the predetermined direction The actual image data of the actual image of the substrate in the state. The substrate inspection device of claim 1 or 2, wherein the parameter calculation unit calculates the correction parameter by performing multiple regression analysis using the substrate shape specified by the shape specifying portion and an equation representing an ellipse. For example, the substrate inspection device of claim 1 or 2, wherein the shape specifying section specifies the shape of the substrate in the actual image by filtering the actual image data obtained by the data obtaining section. The substrate inspection device of claim 1 or 2, further comprising: an imaging unit that generates actual image data by imaging the substrate held by the substrate holding portion by a line sensor extending in the first direction; and A moving part that moves at least one of the substrate holding part and the imaging part in such a manner that the substrate held by the substrate holding part moves relative to the imaging part in a second direction intersecting the first direction; and The data acquisition unit acquires actual image data generated by the imaging unit. A substrate processing apparatus comprising: a film forming section that forms a processing film on a substrate; and the substrate inspection apparatus according to any one of claims 1 to 5, which performs substrate inspection after the processing film is formed by the film forming section . A method for inspecting a substrate, comprising the steps of: holding at least a part of a substrate to be inspected with a circular outer periphery by a substrate holding portion; obtaining an actual image showing the image of the substrate held by the substrate holding portion as an actual image Image data; based on the obtained actual image data, specify the shape of the substrate in the actual image; treat the shape of the substrate in the specified actual image as an elliptical shape, and calculate the major and minor diameters based on the elliptical shape The correction parameters for correcting the actual image data; based on the calculated correction parameters, the actual image data obtained is corrected as the corrected image data in such a way that the long diameter and short diameter of the substrate shape in the actual image become equal; And the substrate is inspected based on the corrected corrected image data; and the inspection target substrate has a non-circular portion to indicate the direction of the substrate; and the step of specifying the outline of the substrate includes the following steps: In the actual image data, set a plurality of imaginary lines extending from the preset origin to the outside; for each of the above plural imaginary lines, detect the absolute value from the outside toward the origin above the specified threshold for the first time The position of the pixel; Excluding the position detected by the imaginary line extending from the origin to the non-circular part from the detected position; Based on a plurality of positions other than the excluded position, specify the substrate and the non-circular part Corresponding part of the actual image data except the actual image of the substrate shape; and the above steps to calculate the correction parameters include: based on the specific shape of the substrate, and the equation representing the ellipse, calculate the ellipse-shaped substrate in the actual image The long diameter and short diameter of the outer shape; the magnification of the long diameter and the short diameter is calculated as the correction parameter. The substrate inspection method of claim 7, wherein the step of holding the substrate of the inspection target by the substrate holding portion includes: holding the substrate by the substrate holding portion such that the non-circular portion of the substrate faces a predetermined direction; and specifying the actual drawing The shape of the substrate in the image includes: by obtaining actual image data showing the actual image of the substrate with the non-circular portion facing the predetermined direction, the actual image of the portion of the substrate corresponding to the non-circular portion is obtained Excluding the data, it specifies the shape of the substrate in the actual image. For example, the substrate inspection method of claim 7 or 8, wherein the step of calculating the above-mentioned correction parameters includes: by performing multiple regression analysis using the specified substrate shape and the equation representing the ellipse Analyze and calculate the correction parameters. For example, the substrate inspection method of claim 7 or 8, wherein the step of identifying the outline of the substrate in the actual image includes: identifying the outline of the substrate in the actual image by filtering the acquired actual image data. Such as the substrate inspection method of claim 7 or 8, further comprising the step of: relatively moving the substrate in a second direction that intersects the first direction with respect to the imaging section including the line sensor extending in the first direction , Moving at least one of the substrate holding part and the imaging part by a moving part; and generating actual image data by photographing the substrate held by the substrate holding part by the imaging part; and obtaining the actual image data Including: obtaining the actual image data generated by the above-mentioned imaging unit. A substrate processing method, comprising the steps of: forming a processing film on a substrate by a film forming portion; and, by the substrate inspection method according to any one of claims 7 to 11, forming a processing film on the film forming portion The substrate is inspected.

Images