WO2014034349A1

WO2014034349A1 - Defect classification device, defect classification method, control program, and recording medium

Info

Publication number: WO2014034349A1
Application number: PCT/JP2013/070531
Authority: WO
Inventors: 山田　栄二
Original assignee: シャープ株式会社
Priority date: 2012-08-31
Filing date: 2013-07-30
Publication date: 2014-03-06
Also published as: JP2014048206A; CN104508469A

Abstract

A defect classification device (1) provided with: a classification index calculation unit (14) for calculating a feature amount indicative of the difference between the color of pixels included in an outer peripheral region, which is a part of the defect region, and the color of pixels in a neighboring region, which is a region outside the defect region and is adjacent to the outer peripheral region; and a defect classification unit (15) for classifying, on the basis of the calculated feature amount, a defect in the defect region as being either in-film foreign matter or on-film foreign matter.

Description

Defect classification apparatus, defect classification method, control program, and recording medium

The present invention relates to defect detection of an inspection object by analyzing an image obtained by photographing the inspection object, and more particularly to classification of detected defects.

Inspecting defects in the manufacturing process of industrial products is important for ensuring the quality of products and is generally performed. Automatic inspection using an inspection apparatus has also been put into practical use.

For example, in the following Patent Document 1, a defect generated in the flat panel display is detected using an input image that is an image of a flat panel display that is an inspection object, and the detected defect is classified by type. It is described.

Japanese Patent Publication “Japanese Patent Laid-Open No. 2012-32369 (Released on February 16, 2012)”

Here, it is known that in a product having a thin film formed on the surface thereof, such as a substrate on which wiring is formed, a defect (hereinafter referred to as an in-film foreign matter) occurs due to foreign matter entering the film. . Further, as a defect that is similar in appearance to a foreign substance in the film, a defect due to the adhesion of the foreign substance on the film (hereinafter referred to as an on-film foreign substance) is also known. Such defects are particularly likely to occur in products manufactured using a CVD (Chemical Vapor Deposition) apparatus.

In-film foreign matter may cause product defects and must be removed with a repair device. On the other hand, since the foreign matter on the film is removed by cleaning, it does not cause a defect. As described above, since the necessary countermeasures are different between the in-film foreign matter and the on-film foreign matter, it is desirable that these defects can be identified.

However, the conventional techniques as described above have a problem that it is difficult to distinguish in-film foreign matter and on-film foreign matter that are similar in appearance, or the identification accuracy is low.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a defect classification apparatus and the like that can identify and classify in-film foreign matter and on-film foreign matter.

In order to solve the above problems, a defect analysis apparatus according to an aspect of the present invention is a defect classification apparatus that classifies defects in a defect region detected in an inspection image obtained by photographing an inspection object having a thin film formed on a surface thereof. A color of a pixel included in the outer peripheral area which is a part of the defective area and is an annular area along the outer periphery of the defective area, and an area outside the defective area, adjacent to the outer peripheral area. A feature amount calculating means for calculating a feature amount indicating a magnitude of a difference from a pixel color of the non-defective region, and a defect in the defective region based on the feature amount calculated by the feature amount calculating means. The thin film is classified as an in-film foreign matter defect in which foreign matter exists on the inner side of the inspection object, or the thin film is classified as a foreign matter defect on the film in which foreign matter exists on the outer side of the inspection object. With defect classification means It is characterized.

A defect analysis method according to an aspect of the present invention is a defect analysis method by a defect classification device that classifies defects in a defect area detected in an inspection image obtained by imaging an inspection object having a thin film formed on a surface thereof. A color of a pixel included in the outer peripheral region which is a part of the defective region and is an annular region along the outer periphery of the defective region, and a non-defect adjacent to the outer peripheral region, which is a region outside the defective region A feature amount calculating step for calculating a feature amount indicating the magnitude of the difference between the colors of the pixels in the region, and a defect in the defective region on the thin film based on the feature amount calculated in the feature amount calculating step. A defect classification step for classifying the defect into an in-film foreign substance defect in which a foreign substance exists on the inner side of the inspection object, or to classify a foreign substance defect on the film in which a foreign substance exists on the outer side of the inspection object with respect to the thin film Including this It is characterized in.

A defect analysis apparatus according to another aspect of the present invention is a defect classification apparatus that classifies defects in a defect area detected in an inspection image obtained by photographing an inspection object having a thin film formed on a surface thereof. A color of a pixel included in the outer peripheral region which is a part of the region and is an annular region along the outer periphery of the defect region, and a color of a pixel in the inner region which is a region other than the outer peripheral region in the defect region Based on the feature quantity calculated by the feature quantity calculation means and the feature quantity calculation means for calculating the feature quantity indicating the difference between the defects, the defect in the defect region is located on the inner side of the inspection object with respect to the thin film. A defect classification means for classifying the defect into an in-film foreign matter defect in which foreign matter exists, or to classify the thin film as a foreign matter defect on the film in which foreign matter exists on the outside of the inspection object with respect to the thin film Yes.

A defect analysis method according to another aspect of the present invention is a defect analysis method by a defect classification device that classifies defects in a defect area detected in an inspection image obtained by photographing an inspection object having a thin film formed on a surface. A color of a pixel included in the outer peripheral region which is a part of the defective region and is an annular region along the outer periphery of the defective region, and an inner region which is a region other than the outer peripheral region in the defective region. A feature amount calculating step for calculating a feature amount indicating a difference from the color of the pixel, and a defect in the defect region on the thin film based on the feature amount calculated in the feature amount calculating step. A defect classification step of classifying the defect as an in-film foreign matter defect in which foreign matter is present on the inside of the film or as a foreign matter defect on the film in which foreign matter is present on the outer side of the inspection object with respect to the thin film. as a feature That.

According to each aspect of the present invention, there is an effect that an in-film foreign matter defect and an on-film foreign matter defect can be identified and accurately classified.

It is a block diagram which shows the principal part structure of the defect classification device which concerns on one Embodiment of this invention. It is a figure explaining the difference between the foreign matter in the film and the foreign matter on the film, the upper side of the figure shows an example of the inspection image in which the foreign matter on the membrane or the foreign matter on the film is photographed, and the lower side of the figure shows the location where the foreign matter has adhered The cross section of is schematically shown. It is a figure which shows an example of the state which divided | segmented the defect area | region into the outer periphery area | region and the internal area | region, and set the neighborhood area | region outside the outer periphery area | region. It is a figure which shows the correlation between the number of true film | membrane foreign materials, and the number of film | membrane foreign materials detected by the said defect classification apparatus. It is a flowchart which shows an example of the defect extraction / classification process which the said defect classification device performs. It is a flowchart which shows an example of the defect classification process performed by S6 of FIG. It is a flowchart which shows an example of the additional determination process which classifies a defect using together the feature-value for another classification | category.

Hereinafter, embodiments of the present invention will be described in detail.

[Configuration of defect classification system]
First, the configuration of the defect classification apparatus according to the present embodiment will be described with reference to FIG. FIG. 1 is a block diagram illustrating an example of a main configuration of the defect classification device 1.

The defect classification apparatus 1 is an apparatus that analyzes and detects defects generated on the surface of an inspection object by analyzing an inspection image that is an image of the product and classifies the detected defects. The defect classification apparatus 1 includes an in-film foreign matter that is a defect caused by foreign matter entering the film and an on-film foreign matter that is a defect caused by foreign matter adhering to the film in an inspection object having a thin film formed on the surface. The main feature point is that it can be classified as follows.

As illustrated, the defect classification apparatus 1 includes a control unit 10, a storage unit 20, and an inspection image input unit 30. Although not shown in the figure, the defect classification device 1 may include an input unit that receives a user input operation, an output unit that outputs a defect detection result and a classification result, and the like.

The control unit 10 controls the functions of the defect classification apparatus 1 in an integrated manner, and includes an alignment unit 11, a defect extraction unit 12, a region setting unit (region setting unit) 13, a classification index calculation unit (feature amount calculation unit, An area width calculation unit, a first difference calculation unit, a second difference calculation unit) 14 and a defect classification unit (defect classification unit) 15 are provided.

The storage unit 20 is a storage device that stores various data used by the defect classification device 1. In the illustrated example, a non-defective image 21, defect determination information 22, and defect classification information 23 are stored.

The inspection image input unit 30 is an interface that accepts input of inspection images. When the size of the inspection object is large, in order to ensure the resolution necessary for defect detection, the entire inspection object is covered by a plurality of imaging operations. That is, in this case, the entire inspection object is inspected by using a plurality of inspection images obtained by imaging different parts of the inspection object. Below, the example which receives the input of the some test | inspection image acquired by each imaging | photography of the different site | part of one test target object is demonstrated. The inspection image may be obtained by photographing an inspection object with a digital camera or the like, for example.

The alignment unit 11 performs alignment (positioning) between the inspection image and the non-defective image 21. As described above, since the non-defective image 21 covers a wider range of the inspection object than the inspection image, the non-defective image 21 and the inspection image cannot be compared without alignment.

For this reason, the alignment unit 11 aligns the non-defective image 21 and the inspection image, cuts out the non-defective image 21 in the aligned region, has the same image size as the inspection image, and is placed on the same part of the inspection object. A corresponding non-defective image 21 is generated.

More specifically, in the alignment between the inspection image and the non-defective image 21, the alignment unit 11 extracts an edge from the non-defective image 21 using a known Laplacian filter or the like to generate a non-defective edge image. Similarly, an inspection edge image is generated for the inspection image. Next, the non-defective edge image is scanned two-dimensionally using the non-defective edge image and the inspection edge image, and correlation values are sequentially calculated for each position. For this, for example, a known template matching method can be used. Then, the position having the highest correlation value is determined as the optimum alignment position. Note that if there is a difference in imaging magnification between the inspection image and the non-defective image 21, the inspection image is enlarged and reduced to obtain an optimum magnification, and the image resizing with the optimum magnification is inspected. Apply to images. In addition, when there is a difference in rotational deformation between the inspection image and the non-defective image 21, an optimum angle is obtained by changing the rotation angle and scanning, and image processing of image rotation at the optimum rotation angle is inspected. Apply to images.

The defect extraction unit 12 compares the inspection image after alignment with the non-defective image 21 after alignment, and extracts a defect area in the inspection image. Specifically, the absolute value of the difference between the pixel values of pixels corresponding to the inspection image and the non-defective product image 21 cut out by the alignment unit 11 (pixels corresponding to the same part of the inspection object) is calculated. Then, each calculated value is compared with a threshold value included in the defect determination information 22, and a pixel that is equal to or greater than the threshold value is determined as a defective pixel corresponding to the defective portion. Then, a region where defective pixels are gathered in the inspection image is extracted as a defective region.

The area setting unit 13 divides the extracted defect area into an inner area and an outer peripheral area, and sets a neighboring area outside the defect area. Details of the setting method of these areas will be described later.

The classification index calculation unit 14 calculates a classification feature amount used for defect classification for each set area (inner area, outer periphery area, and neighboring area). Details of the classification feature amount will be described later.

The defect classification unit 15 classifies the defects using the calculated classification feature amount. Specifically, the defect classification unit 15 compares the above-described classification feature amount with a threshold value included in the defect classification information 23, classifies defects in a defect area that is equal to or greater than the threshold value as in-film foreign matter, and is less than the threshold value. The defect in the defect area is classified as a foreign matter on the film.

The non-defective image 21 is an image showing an inspection object having no defect, and is used for comparison with the inspection image. For example, the non-defective product image 21 may be generated by pasting together a plurality of inspection images confirmed to have no defects. Alternatively, it may be an image created from CAD (Computer Aided Design) data, which is product design information.

The defect determination information 22 is information for determining a defect location in the inspection image, and includes a threshold value for determining whether or not the pixel of the inspection image is a defective pixel.

The defect classification information 23 is information used to classify the detected defect, and indicates a threshold value for classifying the defect area into an inner area and an outer area, and what kind of feature value is used for the defect classification. Information and a threshold value for classifying defects into in-film foreign matter and on-film foreign matter are included.

[In-film foreign matter and foreign matter on membrane]
Here, the details of the in-film foreign matter and the on-film foreign matter will be described with reference to FIG. FIG. 2 is a diagram for explaining the difference between the in-film foreign matter and the on-film foreign matter. The upper side of the figure shows an example of an inspection image in which the in-film foreign matter or the on-film foreign matter is photographed. The cross section of the location to which is attached is schematically shown. Here, an example is shown in which the inspection object is a display panel of a liquid crystal display device in which wiring is formed on a transparent substrate and coated with a thin film having a uniform thickness.

As shown in the figure, in the inspection image obtained by photographing the display panel in which the in-film foreign matter is generated, the portion where the in-film foreign matter is generated is black because it does not transmit light. In addition, the color of the film around the foreign matter in the film changes.

More specifically, there is no foreign matter around the foreign matter in the film, and light is transmitted, so the color is lighter than the location where the foreign matter is present. However, the color is different from that of the normal part on the outer side. For this reason, the area around the in-film foreign matter is also determined as a defective area. Note that, as shown in the lower side of the figure, this color change is presumed to be caused by the change in the film thickness around the foreign matter due to the presence of the foreign matter, thereby changing the thin film interference.

The display panel in which such in-film foreign matter is generated needs to be repaired by sending it to a repair device that removes the in-film foreign matter. That is, it can be said that the in-film foreign matter is a killer defect that requires repair.

On the other hand, even in the inspection image obtained by photographing the display panel where the on-film foreign matter is generated, the portion where the on-film foreign matter is attached is black because it does not transmit light. However, unlike the case of foreign matter in the film, the color of the film around the foreign matter on the film does not change. This is because there is no change in the film thickness around the foreign material, as shown on the lower side of the figure.

Since the foreign matter on the film can be removed by cleaning, it is not necessary to send the display panel in which the foreign matter is detected to the repair device. That is, it can be said that the foreign matter on the film is a non-killer defect that does not require repair.

[Details of defect classification method]
As described above, when the in-film foreign matter is generated, the area along the outer periphery of the detected defect area has a color different from the non-defect area adjacent to the area. For this reason, if the color of the detected peripheral area of the defect area is different from the color of the non-defect area adjacent to the defect area, it can be said that there is a high possibility that the defect area is due to in-film foreign matter.

For this reason, the region setting unit 13 of the defect classification apparatus 1 classifies the defect region into an outer peripheral region and an inner region. The area setting unit 13 sets a neighboring area around the outer peripheral area. These areas are set as shown in FIG. 3, for example. FIG. 3 is a diagram illustrating an example of a state in which a defective area is divided into an outer peripheral area and an inner area, and a neighboring area is set outside the outer peripheral area. In the figure, the area within the distance d from the defect area is set as the vicinity area.

As a method of dividing a defect area into an outer peripheral area and an inner area, a feature quantity (for area discrimination) is calculated for each pixel in the defect area, and a 2 class 1 feature quantity (2 class using the calculated feature quantity is It is possible to apply discriminant analysis of the inner region and the outer peripheral region.

Here, as described with reference to FIG. 2, the outer peripheral region caused by the foreign matter in the film is different in color from the inner region and also in luminance. For this reason, a luminance value or a hue value can be used as the feature amount. In this embodiment, an example in which a luminance value is applied will be described.

When the luminance value is used as a region discriminating feature amount, for each pixel of the defective region, it is determined whether or not the region discriminating feature amount is equal to or greater than a threshold value, thereby determining the defect region as two regions (regions greater than or equal to the threshold value). And the area below the threshold). Of the two regions, the region on the inner side is the inner region, and the region on the outer side is the outer peripheral region.

The distinction between the inside and outside can be made based on the magnitude of the moment. That is, first, the center of gravity of the defect area is obtained, then the moments around the center of gravity of the two areas are calculated, and the area with the smaller moment is set as the inner area, and the area with the larger moment is set as the outer peripheral area. Further, when it is known in advance that the luminance value of the pixel in the inner region is higher than the luminance value of the pixel in the outer peripheral region, such as when the inspection target is a transparent substrate, the luminance value is less than the threshold value. The area may be determined as an internal area.

By such processing, when an in-film defect occurs, the defect region can be divided into an outer peripheral region that is an annular region along the outer periphery and an inner region that is surrounded by the outer peripheral region. .

Furthermore, the region setting unit 13 determines a region having a certain width d (region composed of pixels whose distance to the outer peripheral region is equal to or less than d) in a non-defect region adjacent to the outside of the determined outer peripheral region. Determine as.

Next, for the region determined as described above, the classification index calculation unit 14 calculates a classification feature amount that is an index for defect classification. More specifically, the classification index calculation unit 14 is included in the angular difference θ between the representative value of the hue value of the pixel included in the outer peripheral area and the representative value of the hue value of the pixel included in the neighboring area, and in the outer peripheral area. A representative value r of the saturation of the pixel is calculated, and r × θ obtained by multiplying them is calculated as a defect classification feature amount. The hue is the hue atan2 (b, a) in the Lab color space, and the saturation is the saturation sqrt (a * a + b * b) in the Lab color space.

Then, the defect classification unit 15 compares the calculated classification feature amount with a threshold value included in the defect classification information 23, and determines that it is an in-film foreign matter if the classification feature amount is equal to or greater than the threshold value. If it is less than that, it is determined as a foreign substance on the film. From the results of experiments by the inventors of the present application, it has been confirmed that the degree of difference between the color of the neighboring region and the color of the outer peripheral region, that is, the greater the value of θ, the higher the possibility of being an in-film foreign matter.

The classification feature amount is not limited to the above example as long as it has a value corresponding to the color difference between the outer peripheral region and the neighboring region. For example, the above θ may be used as the classification feature amount. However, as a result of experiments by the inventors of the present application, it has been found that the lower the saturation of the outer peripheral region, the higher the probability that a defect that is not an in-film foreign matter is erroneously determined as an in-film foreign matter. R × θ is preferably used as the classification feature amount rather than the feature amount. The lower the saturation of the outer peripheral region, the smaller the classification feature amount r × θ, and the higher the probability of correctly determining the foreign matter on the film. This is considered to be due to the fact that the value of θ greatly varies with a slight color difference as the saturation is lower.

It is also conceivable that the luminance difference between the outer peripheral area and the neighboring area is used as a classification feature amount. However, as a result of experiments by the inventor of the present application, it has been found that more accurate classification is possible by making a judgment based on the color difference as described above. Therefore, it is desirable to use a classification feature amount proportional to the color difference. .

[Effects of classification]
Here, the effect of the classification of in-film foreign matter and on-film foreign matter by the defect classification apparatus 1 will be described with reference to FIG. FIG. 4 is a diagram showing a correlation between the number of true in-film foreign matter and the number of in-film foreign matter detected by the defect classification apparatus 1.

In the figure, among the (a + b + c + d) input images, the number of true in-film foreign matter (the number of input images in which the in-film foreign matter is actually photographed) is (a + b), and the defect classification device 1 detects The number of in-film foreign matter (number of input images in which the defect classification apparatus 1 has detected the in-film foreign matter) is (b + c). Further, among the in-film foreign matter detected by the defect classification apparatus 1, b is the number of true in-film foreign matter and c is the number that is not the in-film foreign matter. Further, d is the number of input images in which no in-film foreign matter exists and the defect classification apparatus 1 has not detected the in-film foreign matter.

First, as an effect of the classification of the foreign matter on the film and the foreign matter on the film by the defect classification device 1, there is a point that good classification performance can be obtained. Good classification performance is low undetected and overdetected rates. For example, the undetected rate of in-film foreign matter can be expressed as “the number of in-film foreign matters that could not be detected (that is, missed)” / “the number of true in-film foreign matters” = a / (a + b).

Further, the over-detection rate of in-film foreign matter is “number of in-film foreign matter detected by mistake (that is, not really in-film foreign matter)” / “number of input images that are not true in-film foreign matter” = c / (c + d )It can be expressed as.

According to the defect classification apparatus 1, the in-film foreign matter and the on-film foreign matter are classified using the classification feature amount indicating the difference between the color of the pixel included in the outer peripheral region and the color of the pixel included in the neighboring region. It is possible to increase the number b of true in-film foreign matter detected and reduce the number c of in-film foreign matter detected by mistake.

Therefore, the undetected rate: a / (a + b) and the overdetected rate: c / (c + d) can be reduced.

Furthermore, the classification accuracy is improved. The classification accuracy of the in-film foreign matter can be expressed as, for example, “detected true in-film foreign matter” / “number of detected in-film foreign matter” = b / (b + c). As described above, according to the defect classification apparatus 1, b can be increased and c can be decreased, so that the classification accuracy: b / (b + c) can be increased. Further, the classification accuracy of the on-film foreign matter is improved by improving the classification accuracy of the in-film foreign matter.

[Use of classification results]
The classification result of the defect classification apparatus 1 can be used in various ways in the product manufacturing process. For example, it can be used for FDC (Fault Detection and Classification). That is, the defect classification apparatus 1 can detect and monitor the number of in-film foreign matter generated by various production apparatuses for products, and can detect abnormalities in the production apparatus at an early stage.

On the other hand, in the past, the foreign matter on the film and the foreign matter on the film could not be classified with high accuracy, and thus there was a problem that the accuracy of finding an abnormality in the manufacturing apparatus was poor or the discovery was delayed (early discovery was difficult).

Further, according to the defect classification apparatus 1, it is possible to increase the ratio of products having true in-film foreign matter in the products (or parts and semi-finished products in the middle of assembly) to be sent to the repair device for removing the in-film foreign matter. Therefore, the operation rate of the repair device can be improved. Further, it becomes possible to remove all in-film foreign matter by the repair device (improvement of yield).

On the other hand, in the past, in-film foreign matter and on-film foreign matter could not be classified (or classification accuracy was low), and there was a true in-film foreign matter to be repaired among the substrates sent to the repair device. There were few products. For this reason, the operation rate of the repair device is low, and the repair device cannot be efficiently operated. In addition, there is a problem that the repair device cannot remove all the in-film foreign matter (decrease in yield).

In addition, by using the classification result of the defect classification apparatus 1, it is possible to identify a portion where the in-film foreign matter is likely to be generated and a manufacturing condition where the foreign matter is likely to be generated. It is also possible to improve the manufacturing apparatus and change the manufacturing conditions so as to suppress the frequent occurrence of foreign matter in the film.

On the other hand, in the past, it was difficult to classify foreign substances on the film and foreign substances on the film (or the classification accuracy was low), and thus it was difficult to perform such identification by analysis.

Furthermore, by using the classification result of the defect classification apparatus 1, it becomes possible to add up the defect positions and defect sizes at which in-film foreign matter is likely to occur. It is also possible to change the design so that even if foreign matter in the film is generated, it is difficult to cause a defect.

On the other hand, in the past, it was difficult to classify foreign substances on the film and foreign substances on the film (or the classification accuracy was low), and it was difficult to perform such an analysis.

[Process flow]
Next, the flow of defect extraction / classification processing executed by the defect classification device 1 will be described with reference to FIG. FIG. 5 is a flowchart illustrating an example of defect extraction / classification processing.

First, in the defect classification apparatus 1, initialization is performed (S1). As a result, the non-defective image 21, the defect determination information 22, and the defect classification information 23 are read from the storage unit 20 to the control unit 10. Then, a loop of processing for extracting and classifying defects for each inspection image is started (L1).

In the inspection image loop, the alignment unit 11 reads a plurality of images input to the inspection image input unit 30 (S2). Then, the read inspection image is aligned with the good image 21 read in S1 (S3), and the good image 21 is cut out at the alignment position (S4). The cut-out non-defective image 21 is transmitted to the defect extraction unit 12 together with one inspection image to be aligned.

The defect extraction unit 12 that has received the cut-out non-defective image 21 and the inspection image receives the absolute value of the difference between the pixel value of each pixel of the inspection image and the pixel value of the pixel at the corresponding position in the cut-out non-defective image 21. Are calculated respectively. Further, the absolute value of the calculated difference is compared with the threshold value included in the defect determination information 22 read in S1, and a pixel whose absolute value of the difference is greater than or equal to the threshold value is identified as a defective pixel. Then, in the inspection image, an area where the specified defective pixels are collected is extracted as a defective area (S5). A plurality of defect areas may be extracted from one inspection image.

Further, the defect extraction unit 12 transmits information indicating the extracted defect region together with the inspection image to the region setting unit 13, whereby defect classification processing is performed, and the extracted defect region becomes an in-film foreign matter or an on-film foreign matter. It is classified (S6).

On the other hand, the alignment unit 11 that performed the alignment in S3 determines whether the alignment of all the inspection images input to the inspection image input unit 30 has been completed (S7). If it is determined that there is an inspection image for which the alignment has not been completed (NO in S7), the process returns to S2 to read the inspection image for which the alignment has not been completed, and the processing from S3 to S6 is performed on this inspection image. . On the other hand, if it is determined that the alignment of all the inspection images has been completed (YES in S7), the inspection image loop ends and the defect extraction / classification process also ends.

(Defect classification processing)
Next, details of the defect classification process (defect classification method) performed in S6 of FIG. 5 will be described with reference to FIG. FIG. 6 is a flowchart illustrating an example of the defect classification process.

First, the region setting unit 13 calculates a region discriminating feature amount for discriminating between the outer peripheral region and the inner region in the defect region (S10). Specifically, the region setting unit 13 calculates the luminance value of each pixel included in the defect region notified from the defect extraction unit 12 as a region determination feature amount.

Subsequently, the area setting unit 13 determines an inner area and an outer area using the calculated area discriminating feature amount (S11). Specifically, the area setting unit 13 determines, for each pixel in the defect area, whether or not the area determination feature amount is equal to or greater than a threshold value, thereby determining the defect area as two areas (an area equal to or greater than the threshold value). (Area below threshold). Of the two regions, the region on the inner side is the inner region, and the region on the outer side is the outer peripheral region.

Next, the area setting unit 13 determines a neighboring area (S12). Specifically, the region setting unit 13 determines a region that is adjacent to the outside of the outer peripheral region determined in S11 and has a certain width (a region composed of pixels whose distance to the outer peripheral region is equal to or less than a certain region) as a neighboring region. Determine as.

Then, the region setting unit 13 that has determined the internal region, the outer peripheral region, and the neighborhood region as described above notifies the classification index calculation unit 14 of these regions.

Upon receiving this notification, the classification index calculation unit 14 refers to the defect classification information 23 and uses r × θ (r: saturation of the outer peripheral region, θ: hue value of the outer peripheral region and the neighboring region as the classification feature amount. To use).

Then, the hue value of the outer peripheral area and the hue value of the neighboring area are calculated, and the angle difference θ between these hue values is calculated (S13). It should be noted that the hue value of the outer peripheral area only needs to indicate what color the outer peripheral area is, and may be, for example, the arithmetic average value of the hue values of each pixel included in the outer peripheral area, It may be a value or the like. The same applies to the hue value in the vicinity region.

Further, the classification index calculation unit 14 calculates the saturation r of the outer peripheral area (S14), and calculates r × θ obtained by multiplying this by θ calculated in S13 as a defect classification feature amount (S15). This is notified to the defect classification unit 15. Similar to the hue value, the saturation r of the outer peripheral region only needs to indicate what saturation the outer peripheral region is, and is, for example, an arithmetic average value of the saturation of each pixel included in the outer peripheral region. It may be a median value or the like.

The defect classification unit 15 that has received the classification feature quantity compares the classification feature quantity with the defect classification threshold value included in the defect classification information 23, and determines whether the classification feature quantity is equal to or greater than the threshold value (S16).

If it is determined that the threshold value is equal to or greater than the threshold (YES in S16), the defect classification unit 15 determines that the defect occurring in the defect area is due to the in-film foreign matter (S17), and ends the defect classification process. .

On the other hand, if it is determined that it is less than the threshold value (NO in S16), the defect classification unit 15 determines that the defect occurring in the defect area is due to foreign matter on the film (S18), and ends the defect classification process. Although not shown in the illustrated example, the determination result is stored in the storage unit 20 in association with the defective area. The stored determination result may be output and displayed on a display device configured integrally with the defect classification device 1 or connected to the defect classification device 1.

[Additional judgment processing]
In the example of FIG. 6, defects are classified using only one classification feature (r × θ), but the defect classification accuracy can be improved by using other classification features together. Is possible.

This will be described with reference to FIG. FIG. 7 is a flowchart showing an example of an additional determination process for classifying defects by using other classification feature amounts together. The addition determination process is performed when YES is determined in S16 of FIG.

When the defect classification unit 15 determines that the classification feature amount (r × θ) is equal to or greater than the threshold (YES in S16 in FIG. 6), the defect classification unit 15 instructs the classification index calculation unit 14 to calculate the next feature amount. . Upon receiving this instruction, the classification index calculation unit 14 calculates the width of the outer peripheral area (S20), and notifies the defect classification unit 15 of the calculated width.

Note that the width of the outer peripheral region is a numerical value indicating the thickness of the ring of the annular outer peripheral region. For example, among the pixels in the outer peripheral region, the distance from the pixel in the position in contact with the inner region to the pixel in the position in contact with the neighboring region May be calculated as the width of the outer peripheral region. In addition, the width of a plurality of locations is calculated over the entire circumference of the outer peripheral region, and the representative value (arithmetic average value or median) of the calculated width may be used as the width of the outer peripheral region, or the width calculated for one location of the outer peripheral region may be The width of the outer peripheral region may be used as it is.

Upon receiving the notification of the width of the outer peripheral area, the defect classification unit 15 compares the notified width with a threshold corresponding to the width of the outer peripheral area, and determines whether the width is equal to or larger than the threshold (S21).

Note that this determination is to prevent erroneous determination as an in-film foreign object when the width of the outer peripheral region is small enough that it cannot be considered as an in-film foreign object. For this reason, the above threshold value is set to a value that can determine whether or not an outer peripheral region caused by the in-film foreign matter is formed. This threshold value may be stored so that the defect classification unit 15 can be referred to, and may be included in the defect classification information 23, for example.

Here, when it is determined that the width is less than the threshold (NO in S21), the defect classification unit 15 determines that the defect is a foreign substance on the film (S27), and ends the additional determination process. On the other hand, when it is determined that the width is equal to or larger than the threshold (YES in S21), the defect classification unit 15 instructs the classification index calculation unit 14 to calculate the next feature amount.

Upon receiving this instruction, the classification index calculation unit 14 calculates a luminance difference between the outer peripheral region and the inner region (S22), and notifies the defect classification unit 15 of the calculated value. For example, the arithmetic average or median of the luminance values is calculated for each pixel included in the outer peripheral area, and the absolute value of the difference from the arithmetic average or median of the luminance values of each pixel included in the internal area calculated in the same manner is calculated. It is also possible to calculate and use this value as the luminance difference.

The defect classification unit 15 that has received the notification of the luminance difference between the outer peripheral region and the inner region compares the notified luminance difference with a threshold corresponding to the luminance difference between the outer peripheral region and the inner region, and the luminance difference is a threshold value. It is determined whether this is the case (S23).

Note that this determination is erroneously determined as an in-film foreign matter when the difference in luminance value between the inner region and the outer peripheral region is small and it cannot be said that the outer peripheral region due to the in-film foreign matter is formed. This is to prevent this. For this reason, the above threshold value is set to a value that can determine whether or not an outer peripheral region caused by the in-film foreign matter is formed. This threshold value may be stored so that the defect classification unit 15 can be referred to, and may be included in the defect classification information 23, for example.

Here, when it is determined that the luminance difference is less than the threshold (NO in S23), the defect classification unit 15 determines that the defect is a foreign substance on the film (S27), and ends the additional determination process. On the other hand, when it is determined that the luminance difference is equal to or larger than the threshold (YES in S23), the defect classification unit 15 instructs the classification index calculation unit 14 to calculate the next feature amount.

Upon receiving this instruction, the classification index calculation unit 14 calculates a luminance difference between the outer peripheral region and the neighboring region (S24), and notifies the defect classification unit 15 of the calculated value. For example, the arithmetic average or median of the luminance values is calculated for each pixel included in the outer peripheral area, and the absolute value of the difference from the arithmetic average or median of the luminance values of the pixels included in the neighboring area calculated in the same manner is calculated. It is also possible to calculate and use this value as the luminance difference.

The defect classification unit 15 that has received the notification of the luminance difference between the outer peripheral region and the neighboring region compares the notified luminance difference with a threshold value corresponding to the luminance difference between the outer peripheral region and the neighboring region, and the luminance difference is a threshold value. It is judged whether it is less than (S25).

Note that this determination may be misjudged as in-film foreign matter when there is a large difference in brightness between the outer peripheral region and the neighboring region, and it cannot be said that the outer peripheral region due to in-film foreign matter is formed. Is to prevent. For this reason, the above threshold value is set to a value that can determine whether or not an outer peripheral region caused by the in-film foreign matter is formed. As described with reference to FIG. 2, when an in-film foreign matter has occurred, there is a luminance difference between the outer peripheral region and the neighboring region, but a large luminance difference between the inner region and the neighboring region. It will not be. This threshold value may be stored so that the defect classification unit 15 can be referred to, and may be included in the defect classification information 23, for example.

Here, when it is determined that the luminance difference is less than the threshold (YES in S25), the defect classification unit 15 determines that the defect is an in-film foreign matter (S26), and ends the additional determination process. On the other hand, when it is determined that the luminance difference is equal to or greater than the threshold (NO in S25), the defect classification unit 15 determines that the foreign matter is on the film (S27), and ends the additional determination process.

Note that, in S11 of FIG. 6, the inner region and the outer peripheral region are uniformly set regardless of the type of the defect. Therefore, when the defect type is a foreign substance on the film, the outer peripheral region is not circular. Is also envisaged. In such a case, since the location where the width cannot be calculated is detected in S20, the classification index calculation unit 14 notifies the defect classification unit 15 that the width cannot be calculated. In this case, the defect classification unit 15 determines that the foreign matter is on the film and ends the process.

In the above example, the classification index calculation unit 14 calculates all the other classification feature amounts. However, different feature amounts may be calculated by different processing blocks. That is, the classification index calculation unit 14 calculates only r × θ, and the width of the outer peripheral region, the luminance difference between the outer peripheral region and the inner region, and the luminance difference between the outer peripheral region and the neighboring region are different processes. You may make it calculate by a block (not shown in FIG. 1). For example, the block of the area width calculation unit is added to cause the block to calculate the area width, the block of the first difference calculation unit is added to cause the block to calculate the luminance difference between the outer area and the inner area, and the second difference A block of calculation means may be added to cause the block to calculate the luminance difference between the outer peripheral area and the neighboring area.

In the above example, the determination is made using all of the width of the outer peripheral area, the luminance difference between the outer peripheral area and the inner area, and the luminance difference between the outer peripheral area and the neighboring area. It is good also as a structure to use.

The flowcharts of FIGS. 6 and 7 are defect classification processing in which a plurality of classification feature quantities are individually determined sequentially to classify defects. However, the defect classification process is not limited to this. A support vector machine (Support Vector Machine), a neural network, a Bayes classification, or the like may be used as a process for classifying foreign substances on the film and foreign substances on the film using a plurality of classification feature quantities.

[Modification]
The defect classification apparatus 1 performs classification using the classification feature amount indicating the color difference between the outer peripheral region and the neighboring region. However, the defect classification apparatus 1 performs classification using the classification feature amount indicating the color difference between the inner region and the outer peripheral region. It is also possible to perform. As described with reference to FIG. 2, in the case of the in-film foreign matter, the color is different between the outer peripheral region and the inner region of the defect region.

In this case, the area setting unit 13 may set the outer peripheral area and the inner area, and does not need to set the neighboring area. Then, the classification index calculation unit 14 calculates the representative value of the hue in the outer peripheral area and the representative value of the hue in the inner area, and uses the absolute value of the difference as a classification feature amount. The defect classification unit 15 determines the defect as an in-film foreign matter when the color difference between the outer peripheral area and the inner area is large, specifically, when the classification feature amount is equal to or greater than a predetermined threshold.

The defect classification apparatus 1 described above performs both defect detection and classification, but the defect detection and classification may be performed by different apparatuses. That is, the defect classification apparatus 1 does not have to include the alignment unit 11 and the defect extraction unit 12. In this case, a defect detection result is received from a defect detection device that detects a defect, and the defect is classified using the detection result. The defect detection method is not limited to the above example as long as it can identify the defect region in the inspection image.

Furthermore, although the defect classification apparatus 1 described above divides the defect area into an inner area and an outer area, only the inner area may be extracted as a defect area by changing the defect extraction threshold. In this case, an outer peripheral region and a neighboring region may be set in a non-defect region around the defect region. For example, a pixel whose distance to the defect area is equal to or less than D may be set as the vicinity area, and the peripheral area may be set by performing discriminant analysis based on the luminance value in the vicinity area.

The inspection object is not particularly limited as long as it can cause in-film foreign matter and foreign matter on the film, that is, a thin film formed on the surface. For example, the display part of a display panel, a semiconductor wafer, or a thin film solar cell substrate may be used.

[Summary]
A defect analysis apparatus (1) according to an aspect of the present invention is a defect classification apparatus that classifies defects in a defect area detected in an inspection image obtained by photographing an inspection object having a thin film formed on a surface thereof. A color of a pixel included in the outer peripheral region which is a part of the region and is an annular region along the outer periphery of the defect region, and a non-defect region (neighboring adjacent to the outer peripheral region) A feature amount calculation unit (classification index calculation unit 14) that calculates a feature amount indicating the magnitude of the difference between the pixel color of the region and the defect region based on the feature amount calculated by the feature amount calculation unit. Are classified as in-film foreign matter defects in which foreign matter exists on the inner side of the inspection object with respect to the thin film, or on the film in which foreign matter exists on the outer side of the inspection object with respect to the thin film. Defect classification means for classifying foreign object defects (defects It is characterized in that it comprises a section 15) and.

According to the above configuration, the feature amount indicating the difference between the color of the pixel included in the outer peripheral region that is an annular region along the outer periphery of the defective region and the color of the pixel in the non-defective region adjacent to the outer peripheral region is calculated. . Then, based on the calculated feature amount, the defect in the defect region is classified as an in-film foreign matter defect or an on-film foreign matter defect.

As described with reference to FIG. 2, in the case of an in-film foreign matter defect, a difference occurs in the color between the outer peripheral region and the non-defect region (neighboring region) adjacent to the outer peripheral region. Therefore, the in-film foreign matter defect and the on-film foreign matter defect can be identified and classified with high accuracy.

The defect analysis apparatus according to an aspect of the present invention preferably includes a region setting unit (region setting unit 13) that sets the outer peripheral region based on a luminance value of each pixel included in the defective region. .

As described with reference to FIG. 2, in the case of an in-film foreign matter defect, a luminance difference is generated between the outer peripheral region and the inner region of the defective region. Therefore, according to the above configuration, a non-defective region (neighboring region) It is possible to appropriately set the outer peripheral region to be compared with the color difference.

In the defect analysis apparatus according to an aspect of the present invention, the feature amount calculation unit includes a representative value of a hue of a pixel included in the outer peripheral area and a representative value of a hue of a pixel included in the non-defective area. A value obtained by multiplying the difference by the representative value of the saturation of the pixels included in the outer peripheral region is preferably calculated as the feature amount.

According to the above configuration, a value obtained by multiplying the difference between the representative values of the hue by the representative value of the saturation is calculated as the feature amount. Since the difference between the representative values of the hues indicates the color difference as a numerical value, the feature amount including the difference reflects the magnitude of the color difference between the outer peripheral area and the non-defective area. The representative value is a value representative of the area, and is a value indicating what hue or saturation the area has. As a specific example, an arithmetic average value, a median value, or the like of the hue (or saturation) of each pixel included in the region can be used as a representative value.

Further, as described above, it is known that the lower the saturation of the outer peripheral region, the higher the probability that a defect that is not an in-film foreign matter is determined as an in-film foreign matter defect. Therefore, by using the value obtained by multiplying the saturation of the outer peripheral region by the difference between the representative values of the hue as the feature amount, the probability of erroneously determining a defect that is not actually an in-film foreign matter defect as an in-film foreign matter defect is reduced. be able to.

The defect analysis apparatus according to an aspect of the present invention includes a region width calculation unit (classification index calculation unit 14) that calculates a ring width of the outer peripheral region, and the defect classification unit includes the feature amount calculation unit. The calculated feature amount is not less than a predetermined threshold value for defect classification based on color, and the width calculated by the area width calculating means is not less than a predetermined threshold value for defect classification based on the area width. In this case, it is preferable to classify the defect in the defect region as an in-film foreign matter defect.

According to the above configuration, when the feature amount calculated by the feature amount calculation unit is equal to or greater than the threshold value and the ring width of the outer peripheral region is equal to or greater than the threshold value, the defect in the defect region is classified as an in-film foreign matter defect. .

This makes it possible to prevent erroneous determination of this as an in-film foreign matter defect when the width of the outer peripheral region is so small that it cannot be considered as an in-film foreign matter defect.

The defect analysis apparatus according to one embodiment of the present invention includes a representative value of luminance values of pixels included in the outer peripheral region and luminance values of pixels included in an inner region that is an area other than the outer peripheral region in the defect region. First difference calculation means (classification index calculation unit 14) for calculating a difference from a representative value of the value, wherein the defect classification means is used for defect classification based on a color based on the feature quantity calculated by the feature quantity calculation means. When the difference between the luminance values calculated by the first difference calculating means is equal to or greater than a predetermined threshold for defect classification based on the luminance difference between the outer peripheral area and the inner area. In addition, it is preferable to classify the defect in the defect region into an in-film foreign matter defect.

According to the above configuration, the feature amount calculated by the feature amount calculation unit is equal to or greater than the threshold value, and the representative value of the luminance value of the pixel included in the outer peripheral region and the representative value of the luminance value of the pixel included in the inner region are Is equal to or greater than the threshold value, the defect in the defect region is classified as an in-film foreign matter defect.

As a result, when the difference between the luminance values of the inner region and the outer peripheral region is small and it cannot be said that the outer peripheral region due to the in-film foreign matter defect is formed, this is erroneously determined as the in-film foreign matter defect. It becomes possible to prevent.

The defect analysis apparatus according to one aspect of the present invention calculates a difference between a representative value of luminance values of pixels included in the outer peripheral area and a representative value of luminance values of pixels included in the non-defective area. 2 difference calculation means (classification index calculation unit 14), wherein the defect classification means has the feature quantity calculated by the feature quantity calculation means equal to or greater than a predetermined threshold for defect classification based on color, and If the difference between the brightness values calculated by the second difference calculation means is less than a predetermined threshold for defect classification based on the brightness difference between the outer peripheral area and the non-defect area, the defect in the defect area is detected in the film. It is preferable to classify as foreign matter defects.

According to the above configuration, the feature value calculated by the feature value calculation unit is equal to or greater than the threshold value, and the representative value of the luminance value of the pixel included in the outer peripheral area and the representative value of the luminance value of the pixel included in the non-defective area Is less than the threshold value, the defect in the defect region is classified as an in-film foreign matter defect.

As a result, when the luminance difference between the outer peripheral region and the non-defect region is large and it cannot be said that the outer peripheral region due to the in-film foreign matter defect is formed, this is erroneously determined as the in-film foreign matter defect. It becomes possible to prevent.

A defect analysis method according to another aspect of the present invention is a defect analysis method by a defect classification device that classifies defects in a defect area detected in an inspection image obtained by photographing an inspection object having a thin film formed on a surface. A color of a pixel included in the outer peripheral region which is a part of the defective region and is an annular region along the outer periphery of the defective region, and an inner region which is a region other than the outer peripheral region in the defective region. A feature amount calculating step for calculating a feature amount indicating a difference from the color of the pixel, and a defect in the defect region on the thin film based on the feature amount calculated in the feature amount calculating step. A defect classification step of classifying the defect as an in-film foreign matter defect in which foreign matter is present on the inside of the film or as a foreign matter defect on the film in which foreign matter is present on the outer side of the inspection object with respect to the thin film. As a feature There.

According to the above configuration, the color of the pixel included in the outer peripheral region that is an annular region along the outer periphery of the defect region, and the region other than the outer peripheral region in the defect region, that is, the pixels in the inner region surrounded by the outer peripheral region. A feature amount indicating a difference from the color is calculated. Then, based on the calculated feature amount, the defect in the defect region is classified as an in-film foreign matter defect or an on-film foreign matter defect.

As described with reference to FIG. 2, in the case of an in-film foreign matter defect, a color difference occurs between the outer peripheral region and the inner region of the defect region. It is possible to identify foreign matter defects on the film and classify them with high accuracy.

The defect classification apparatus may be realized by a computer. In this case, a control program for realizing the defect classification apparatus by a computer by operating the computer as each unit of the defect classification apparatus, and A computer-readable recording medium on which it is recorded also falls within the scope of the present invention.

The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention.

[Example of software implementation]
Finally, each block of the defect classification apparatus 1, particularly the control unit 10, may be realized by hardware by a logic circuit formed on an integrated circuit (IC chip), or a CPU (Central Processing Unit) is used. It may be realized by software.

In the latter case, the defect classification apparatus 1 includes a CPU that executes instructions of a program that realizes each function, a ROM (Read Memory) that stores the program, a RAM (Random Access Memory) that expands the program, the program, A storage device (recording medium) such as a memory for storing various data is provided. An object of the present invention is a recording medium on which a program code (execution format program, intermediate code program, source program) of a control program of the defect classification apparatus 1 which is software for realizing the functions described above is recorded so as to be readable by a computer. This can also be achieved by supplying the defect classification apparatus 1 and reading and executing the program code recorded on the recording medium by the computer (or CPU or MPU).

Examples of the recording medium include non-transitory tangible media, such as magnetic tapes and cassette tapes, magnetic disks such as floppy (registered trademark) disks / hard disks, and CD-ROM / MO. Discs including optical disks such as / MD / DVD / CD-R, cards such as IC cards (including memory cards) / optical cards, and semiconductor memories such as mask ROM / EPROM / EEPROM (registered trademark) / flash ROM Alternatively, logic circuits such as PLD (Programmable logic device) and FPGA (Field Programmable Gate array) can be used.

Further, the defect classification apparatus 1 may be configured to be connectable to a communication network, and the program code may be supplied via the communication network. The communication network is not particularly limited as long as it can transmit the program code. For example, the Internet, intranet, extranet, LAN, ISDN, VAN, CATV communication network, virtual private network (Virtual Private Network), telephone line network, mobile communication network, satellite communication network, etc. can be used. The transmission medium constituting the communication network may be any medium that can transmit the program code, and is not limited to a specific configuration or type. For example, even in the case of wired lines such as IEEE1394, USB, power line carrier, cable TV line, telephone line, ADSL (Asymmetric Digital Subscriber Line) line, infrared rays such as IrDA and remote control, Bluetooth (registered trademark), IEEE 802.11 wireless, HDR ( It can also be used by wireless such as High Data Rate, NFC (Near Field Communication), DLNA (Digital Living Network Alliance), mobile phone network, satellite line, terrestrial digital network. The present invention can also be realized in the form of a computer data signal embedded in a carrier wave in which the program code is embodied by electronic transmission.

The present invention can be used for defect inspection of industrial products.

DESCRIPTION OF SYMBOLS 1 Defect classification apparatus 13 Area | region setting part (area | region setting means)
14 Classification index calculation unit (feature amount calculation means, region width calculation means, first difference calculation means, second difference calculation means)
15 Defect classification part (defect classification means)

Claims

A defect classification device for classifying defects in a defect area detected in an inspection image obtained by photographing an inspection object having a thin film formed on a surface,
A non-defective region that is a part of the defective region and is a color of a pixel included in the outer peripheral region that is an annular region along the outer periphery of the defective region, and a region outside the defective region and adjacent to the outer peripheral region Feature amount calculating means for calculating a feature amount indicating the magnitude of the difference from the color of the pixel;
Based on the feature amount calculated by the feature amount calculation means, classify the defect in the defect area into an in-film foreign matter defect in which foreign matter exists on the inner side of the inspection object with respect to the thin film, or A defect classification apparatus comprising: a defect classification unit that classifies a thin film as a foreign matter defect on a film in which foreign matter is present on the outside of the inspection object.
The defect classification apparatus according to claim 1, further comprising region setting means for setting the outer peripheral region based on a luminance value of each pixel included in the defect region.
The feature amount calculating means calculates a saturation of a pixel included in the outer peripheral area by a difference between a representative value of the hue of the pixel included in the outer peripheral area and a representative value of the hue of the pixel included in the non-defective area. The defect classification apparatus according to claim 1, wherein a value obtained by multiplying a representative value is calculated as the feature amount.
An area width calculating means for calculating the width of the ring of the outer peripheral area;
The defect classification means has the feature quantity calculated by the feature quantity calculation means equal to or larger than a predetermined threshold for defect classification based on color, and the width calculated by the area width calculation means is based on the area width. The defect classification apparatus according to any one of claims 1 to 3, wherein a defect in the defect region is classified as an in-film foreign matter defect when the threshold value is equal to or greater than a predetermined threshold for defect classification.
First difference calculation for calculating a difference between a representative value of luminance values of pixels included in the outer peripheral area and a representative value of luminance values of pixels included in an internal area other than the outer peripheral area in the defect area With means,
The defect classification means has a feature value calculated by the feature quantity calculation means that is equal to or greater than a predetermined threshold for defect classification based on color, and a difference between luminance values calculated by the first difference calculation means is 5. The defect in the defect region is classified as an in-film foreign matter defect when the defect is equal to or greater than a predetermined threshold for defect classification based on a luminance difference between the outer peripheral region and the inner region. The defect classification device according to any one of the above.
A second difference calculating means for calculating a difference between a representative value of luminance values of pixels included in the outer peripheral area and a representative value of luminance values of pixels included in the non-defective area;
The defect classification means has a feature value calculated by the feature quantity calculation means that is equal to or greater than a predetermined threshold for defect classification based on color, and a difference in luminance value calculated by the second difference calculation means is: 2. The defect in the defect area is classified as an in-film foreign matter defect when the defect area is less than a predetermined threshold for defect classification based on a luminance difference between the outer peripheral area and the non-defect area. The defect classification apparatus according to any one of 5.
A defect classification device for classifying defects in a defect area detected in an inspection image obtained by photographing an inspection object having a thin film formed on a surface,
The color of the pixels included in the outer peripheral region that is a part of the defective region and is an annular region along the outer periphery of the defective region, and the pixels in the inner region that is the region other than the outer peripheral region in the defective region A feature amount calculating means for calculating a feature amount indicating a difference from the color;
Based on the feature amount calculated by the feature amount calculation means, classify the defect in the defect area into an in-film foreign matter defect in which foreign matter exists on the inner side of the inspection object with respect to the thin film, or A defect classification apparatus comprising: a defect classification unit that classifies a thin film as a foreign matter defect on a film in which foreign matter is present on the outside of the inspection object.
A defect analysis method by a defect classification device for classifying defects in a defect area detected in an inspection image obtained by photographing an inspection object having a thin film formed on a surface,
A non-defective region that is a part of the defective region and is a color of a pixel included in the outer peripheral region that is an annular region along the outer periphery of the defective region, and a region outside the defective region and adjacent to the outer peripheral region A feature amount calculating step for calculating a feature amount indicating the magnitude of the difference from the color of the pixel;
Based on the feature amount calculated in the feature amount calculation step, the defect in the defect region is classified as an in-film foreign matter defect in which foreign matter exists on the inner side of the inspection object with respect to the thin film, or And a defect classification step of classifying the thin film into a foreign matter defect on the film in which foreign matter exists on the outside of the inspection object.
A defect analysis method by a defect classification device for classifying defects in a defect area detected in an inspection image obtained by photographing an inspection object having a thin film formed on a surface,
The color of the pixels included in the outer peripheral region that is a part of the defective region and is an annular region along the outer periphery of the defective region, and the pixels in the inner region that is the region other than the outer peripheral region in the defective region A feature amount calculating step for calculating a feature amount indicating a difference from the color;
Based on the feature amount calculated in the feature amount calculation step, the defect in the defect region is classified as an in-film foreign matter defect in which foreign matter exists on the inner side of the inspection object with respect to the thin film, or And a defect classification step of classifying the thin film into a foreign matter defect on the film in which foreign matter exists on the outside of the inspection object.
A control program for operating the defect classification apparatus according to any one of claims 1 to 7, wherein the control program causes a computer to function as each of the above means.
A computer-readable recording medium on which the control program according to claim 10 is recorded.