KR102234984B1 - Apparatus for detecting particle of a semiconductor wafer - Google Patents

Abstract

The present invention relates to an apparatus for detecting a particle of a wafer in the process of manufacturing a semiconductor element. The apparatus for detecting a particle according to an embodiment of the present invention comprises: a first imaging module for capturing the front surface of a wafer for each horizontal linear area and extracting information on a distance value through captured image data; a second imaging module for capturing the rear surface of the wafer for each horizontal linear area and extracting information on a distance value through captured image data; a particle monitoring device for sequentially detecting particles exceeding a preset prescribed value for each horizontal linear area by analyzing information on at least one among the distance, height, and volume values from the image data captured for each horizontal linear area by the first and second imaging modules. The apparatus for detecting a particle is capable of accurately calculating the presence and location of a particle in real-time.

Description

Particle detection device of semiconductor wafer {APPARATUS FOR DETECTING PARTICLE OF A SEMICONDUCTOR WAFER}

The present invention relates to a semiconductor manufacturing equipment, and in detail, a particle detection device of a semiconductor wafer capable of accurately detecting particles in real time by analyzing respective front and rear imaging results of a wafer in process for manufacturing a semiconductor device. It is about.

In general, when manufacturing a semiconductor component such as a semiconductor device or a display panel, predetermined patterns are formed on a semiconductor wafer. For this purpose, a process of coating a photoresist on a semiconductor wafer, exposing and developing, etc. is repeatedly performed. .

When coating a photoresist, a semiconductor wafer is mounted on a loading stage of a coating apparatus equipped with a spindle or a printing device, and then photoresist printing and coating processes are performed.

Subsequently, when the photoresist is exposed, the photoresist-coated wafer is put in and seated in an exposure apparatus, and then an exposure process is performed with an exposure machine. In this case, the exposure apparatus performs a process of transferring the chromium pattern of the reticle to the photoresist film using light.

In this way, in order to perform a photoresist coating and exposure process, a wafer placed on a loading stage or an exposure chuck needs to be maintained in flatness and horizontality.

If the wafer is placed unevenly or not horizontally on the loading stage or the exposure chuck, the thickness is not constant during coating, and the exposure light cannot be irradiated at the correct position during exposure. In this way, the main reason that the flatness and horizontality of the wafer is not maintained may be particles present in the wafer. Therefore, before performing the coating and exposure processes, a process of detecting particles remaining on the wafer must be preceded.

In addition, when particles exist on the wafer, it is impossible to accurately and accurately form a desired thickness pattern on the wafer by the particles.

Thus, conventionally, a laser is irradiated with a light-emitting sensor on the surface of a wafer that is input to a coating device or an exposure device, and the laser reflected from the surface of the wafer is received by the light-receiving sensor. Detected.

However, the conventional method for detecting particles using a laser has a problem in that it is not possible to determine the exact size and number of particles. That is, there is a problem in that it is not possible to determine an accurate volume, such as whether particles having a volume larger than the specified exist on the front surface of the wafer, on the loading stage or the exposure chuck, or on the rear surface of the wafer.

In addition, since the laser light-emitting sensor and the light-receiving sensor must be disposed facing the front or back of the wafer for inspection, or disposed in parallel, there is a problem in that the arrangement and application structure of the particle detection device is complicated and space utilization is not easy. .

The present invention is to solve the above problems, a semiconductor capable of accurately detecting particles having a size larger than specified in real time by photographing the front and rear surfaces of a wafer for semiconductor device manufacturing with an imaging device, respectively, and analyzing the imaging results. An object thereof is to provide an apparatus for detecting particles of a wafer.

In particular, it is possible to photograph the wafer in line form using an image pickup device such as a line image sensor without using a general laser emission and light receiving device, and to calculate the presence, size, and number of particles through image processing and analysis technology. An object thereof is to provide an apparatus for detecting particles of a semiconductor wafer.

The objects of the present invention are not limited to the above-mentioned objects, and other objects and advantages of the present invention that are not mentioned can be understood by the following description, and will be more clearly understood by examples of the present invention. In addition, it will be easily understood that the objects and advantages of the present invention can be realized by the means shown in the claims and combinations thereof.

The particle detection apparatus of a semiconductor wafer according to an embodiment of the present invention for achieving various purposes as described above photographs a partial area of the front surface of a wafer rotating on an exposure chuck or loading stage for each horizontal line area, and distance through the captured image data. A first imaging module for extracting value information, and a second imaging module for photographing a partial area of a rear surface of the rotating wafer for each horizontal line area and extracting distance value information through the captured image data.

In addition, particle monitoring that sequentially detects particles of more than a predetermined standard for each horizontal line area by analyzing at least one of distance, height, and volume values from the image data captured by the first and second imaging modules for each horizontal line area. Including devices.

The particle monitoring device according to an embodiment of the present invention samples distance and height value information included in front and rear image data respectively input through the first and second imaging modules. Then, after filtering and extracting distance and height value information for each frame of front and rear image data, a distance and height map for each horizontal line region is generated.

Accordingly, the particle monitoring device according to an embodiment of the present invention maps distance and height value information of image data for each frame for each of a plurality of preset blocks or division points, so that an area for each block, an area for each horizontal line area, and a block A star distance and height map may be generated, and particles and sizes of particles may be detected.

The particle detection apparatus of a semiconductor wafer according to an embodiment of the present invention having the above-described technical features detects particles by analyzing the front and rear imaging results of the semiconductor wafer, so that the size and number of particles can be more accurately detected in real time. .

In addition, by taking a line image of the wafer using an imaging device such as a line image sensor from the long-distance side of the rotating wafer, and calculating the presence and location of particles larger than the predetermined size through image processing and analysis technology, the particle detection device Simplify the layout structure and increase the space utilization.

Above, in addition to the above-described effects, specific effects of the present invention will be described together while describing specific details for carrying out the invention.

1 is a diagram showing in detail a particle detection apparatus and a particle detection method of a semiconductor wafer according to an embodiment of the present invention.
FIG. 2 is a side view illustrating a particle detection method of the particle detection apparatus shown in FIG. 1.
3 is a block diagram showing detailed components of the particle monitoring device shown in FIGS. 1 and 2.
4 is a diagram illustrating a method of detecting a wafer imaging distance of the first and second imaging modules shown in FIG. 3.
5 is a block diagram illustrating in detail the components of the particle determination unit shown in FIG. 3.
FIG. 6 is a diagram illustrating a method of checking information on a detection area area, distance, and height map of a particle extracting unit illustrated in FIG. 5, and a method of detecting a size of a particle.

The above-described objects, features, and advantages will be described later in detail with reference to the accompanying drawings, and accordingly, a person of ordinary skill in the art to which the present invention pertains will be able to easily implement the technical idea of the present invention. In the present application, terms such as "consist of" or "include" should not be construed as necessarily including all of the various elements or various steps described in the specification, and some of the elements or some steps It may not be included, or it should be interpreted that it may further include additional components or steps. In addition, a singular expression used in the present specification includes a plurality of expressions unless the context clearly indicates otherwise.

Hereinafter, an apparatus for detecting particles of a semiconductor wafer according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram showing in detail a particle detection apparatus and a particle detection method of a semiconductor wafer according to an embodiment of the present invention. And, FIG. 2 is a side view showing a particle detection method of the particle detection apparatus shown in FIG. 1.

1 and 2, the particle detection apparatus of the present invention includes a first imaging module 111, a second imaging module 112, and a particle monitoring device 200.

The first imaging module 111 photographs a partial area of the front surface of the wafer W rotating in the direction A horizontal to the ground on the exposure chuck or loading stage LS in a line form, and stores distance value information through the captured image data. Extract.

Specifically, the first imaging module 111 sequentially and continuously photographs a front half portion (eg, a radius portion) of the rotating wafer W for each longer horizontal line area in the horizontal direction. In addition, partial image data in the form of a horizontal line is sequentially output. In addition, the first imaging module 111 may transmit and detect a signal for distance measurement in the form of a horizontal line, and sequentially output distance value information for a horizontal line area. In this case, a signal such as ultrasonic waves or infrared rays may be transmitted to measure the distance value. In addition, image data and distance value information for each horizontal line area on the front surface that are sequentially detected are transmitted to the particle monitoring device 200 in real time.

The second imaging module 112 photographs a partial area of the rear surface of the wafer W rotating in the direction A horizontal to the ground on the exposure chuck or loading stage LS in a line shape, and extracts distance information through the captured image data. do.

Specifically, the second imaging module 112 sequentially and continuously photographs the rear radius portion of the rotating wafer W (here, excluding the loading stage LS) for each longer horizontal line area in the horizontal direction. It sequentially generates and outputs some image data on the back of the line. In addition, the second imaging module 112 may transmit and detect a signal for measuring distances of horizontal line regions on the rear surface of the wafer W, and sequentially output distance value information for the horizontal line regions. In this case, a signal such as ultrasonic waves or infrared rays may be transmitted to measure the distance value. In addition, image data and distance value information for each horizontal line area on the rear surface that are sequentially detected are transmitted to the particle monitoring device 200 in real time.

The first and second imaging modules 111 and 112 described above use at least one imaging device such as a CCD image sensor, a CMOS image sensor, a line-type CCD image sensor, and a 3D camera, thereby providing distance and height values for each detection area in the form of a horizontal line. Image data including information can be output.

Specifically, a CCD image sensor, a CMOS image sensor, and a 3D camera convert an image formed by light reflected from an imaged object passing through the lens and hitting the light receiving element into an electrical signal according to the intensity of light and converting it into an analog electrical signal. Will be printed. Accordingly, the first and second imaging modules 111 and 112 convert analog electrical signals for image detection areas sensed through imaging elements into digital values, and map the converted digital values with points or coordinates in the image data to monitor particles. It is transmitted to the device 200. The digital values mapped to points or coordinates in the image data are used as distance values and height (z) values of the image detection areas. A distance value and an area are derived based on any one image sensor, and a height (z) value is derived based on a lower coordinate of the image data for each frame. In this way, at least one imaging device can derive volume (x,y,z), distance and height (z) value information, area information, etc. from frame-by-frame image data according to the resolution of the device to be photographed. An example in which a CCD image sensor or a 3D camera is used will be described.

The horizontal line regions detected through the imaging elements of the first and second imaging modules 111 and 112 may be displayed in a three-dimensional form on a screen having a preset resolution. That is, image data is spatial data that detects volume (x,y,z), distance, and height (z) value information according to the resolution of the imaging devices, and the image data detection areas are based on the resolution and detectable range of the imaging devices. Can be set. Accordingly, the image data detection area of the imaging devices may be set in the form of a rectangular or rectangular parallelepiped in the form of a horizontal line having a longer distance in the horizontal direction.

The particle monitoring device 200 includes a distance, a height (z), and a volume (x) extracted from the front and rear image data for each horizontal line area imaged by the first and second imaging modules 111 and 112, and the front and rear image data, respectively. By analyzing at least one of the values of ,y,z), the area for each horizontal line area and particles that are larger than the specified size (a preset reference size) existing in the front and rear surfaces are sequentially detected.

Specifically, the particle monitoring device 200 AD-converts signals input through the first and second imaging modules 111 and 112, and samples distance and height (z) value information included in the image data. And, after filtering and extracting at least one of the distance, height (z), and volume (x,y,z) values in every frame unit, the volume (x,y,z) for each frame for horizontal line regions , Generate at least one of a distance, area, and height map. At this time, the particle monitoring device 200 maps the volume (x,y,z), distance, and height (z) value information of image data for each frame into a two-dimensional or three-dimensional form with a preset resolution, and By dividing into and matching distance and height value information for each of a plurality of dividing points, at least one of a block-by-block distance, area, and height map for detection regions may be generated. Particles having a predetermined size (a preset reference size) or more are detected from at least one of the block-by-block distance, area, and height maps. Here, N and M are natural numbers excluding 0 that are the same or different from each other.

Subsequently, the particle monitoring device 200 compares the volume (x,y,z), distance, and height value information of blocks or points adjacent to each other according to a preset resolution, and compares the volume (x,y,z) and distance information. And it may be determined that the particle exists at a location where the difference in height is greater than or equal to a preset reference.

In contrast, the particle monitoring device 200 arranges volume (x,y,z), distance, and height value information for the detected horizontal line area or blocks according to a preset resolution, and the volume (x ,y,z), distance, and height value information may be compared, and a difference in volume (x,y,z), distance, and height value may be compared with a preset reference value. In addition, it may be determined that particles are present in positions where the difference between the compared volume (x, y, z), distance, and height values is greater than or equal to a preset reference value.

3 is a block diagram showing detailed components of the first and second imaging modules and the particle monitoring device shown in FIGS. 1 and 2.

Referring to FIG. 3, the first imaging module 111 includes a first image sensor unit 101. The first image sensor unit 101 generates image data of horizontal line regions by capturing horizontal line regions on the front surface of the wafer W.

The first imaging module 111 transmits and receives infrared or ultrasonic signals for each preset block or point in horizontal line areas using a first distance detection sensor (not shown) to provide a preset distance or height for each block or point. Value information can be calculated separately.

The second imaging module 112 includes a second image sensor unit 103. The second image sensor unit 103 generates image data of the horizontal line regions by capturing horizontal line regions on the rear surface of the wafer W.

The second imaging module 112 transmits and receives infrared or ultrasonic signals for each preset block or point in horizontal line areas using a second distance detection sensor (not shown) to provide a preset distance or height for each block or point. You can also calculate the value separately.

As described above, the first and second image sensor units 101 and 103 include at least one image sensor of a CCD image sensor, a CMOS image sensor, and a 3D camera, an AD conversion circuit, a data detection filter, a memory, a data transmission/reception module, and the like. It can be configured to include. Accordingly, the first and second image sensor units 101 and 103 may digitally process the distance value and height value information of the horizontal line regions detected according to the resolution of the image sensor itself and transmit the digital signal to the particle monitoring device 200.

Spaces sensed by the first and second image sensor units 101 and 103, that is, horizontal line regions, may be preset as a three-dimensional space on a screen having a preset resolution. That is, as a space in which the image sensor detects a distance value according to the resolution of the image sensors, the sensing space may be set by the resolution of the image sensor and a detectable range. As an example, horizontal line regions in which image data is detected may be configured in a rectangular parallelepiped shape corresponding to a shape of a rectangular screen.

Unlike the first and second image sensor units 101 and 103, the first and second distance detection sensors, which may include the first and second imaging modules, may be selectively included as needed. Here, the first and second distance detection sensor units 102 and 104 may be configured to increase accuracy of information on at least one of a distance, an area, and a height map. To this end, distance value information for each block or point of horizontal line regions generated through the first and second image sensor units 101 and 103 and the distance value of the sensing space detected through the first and second image sensor units 101 and 103 The information can be mapped and used according to preset resolution information.

However, as described above, the calculation of the area (x,y) and height (z) of the horizontal line area determines the alignment reference point of the wafer as the starting point, and the area (x,y) in the image frame signal measured from the image sensor ) Can be calculated and the height (z) can be calculated as the strength of the m signal.

FIG. 4 is a diagram illustrating a method of detecting a wafer imaging distance of the first and second imaging modules shown in FIG. 3.

Referring to FIG. 4 along with FIG. 3, the first and second distance detection sensors transmit and receive signals such as ultrasonic waves or infrared rays through a plurality of preset division blocks or division points, and determine the intensity or magnitude of the signal (ΔV). Accordingly, distance value and height value information are detected for each divided block or point of the detection area DM. In other words, unlike a method of detecting distance value information of the detection area DM through each of the first and second image sensor units 101 and 103, the first and second distance sensors transmit and receive infrared or ultrasonic signals. Distance value or height value information of the detected area DM may be calculated.

Each of the first and second distance detection sensors detects distance information for each of a plurality of division points, digitally processes the distance information for each division point, and transmits the digital signal to the particle monitoring device 200. To this end, the transmission/reception module 120 may include an infrared transmission/reception module or an ultrasonic transmission/reception module, and the plurality of division points may be divided into N×M points according to the location and resolution of the transmission/reception point of each transmission/reception module.

As shown in FIG. 3, the particle monitoring device 200 includes an image converter 210, a particle determination unit 220, and a transmission unit 230.

The image converter 210 processes distance value information of the sensing space input through the first and second image sensor units 101 and 103 to generate a distance map of horizontal line regions. At this time, the image converter 210 filters and samples distance value information input through the first and second image sensor units 101 and 103, maps according to preset resolution information, and maps the detected horizontal line area to the volume of each frame. Generate at least one of (x,y,z), a distance map, or a height map. The image converter 210 may directly transmit a distance map for each frame of the front and rear surfaces to the particle determination unit 220.

In addition, the image converter 210 signal-processes the distance or height value information of the horizontal line region input through the first and second distance detection sensor units 102 and 104 to determine the volume (x,y,z) and distance of the sensing space. Or it creates at least one of the height maps. In this case, similarly, distance or height value information input through the first and second distance detection sensor units 102 and 104 is sampled and filtered, and volume (x,y,z) for horizontal line regions, distance map, or Create a height map.

Specifically, the image converter 210 includes a distance map for each frame generated using the first and second image sensor units 101 and 103 and a distance or height for each frame generated using the first and second distance detection sensors. The map may be mapped to the same resolution set in advance, divided into preset blocks, and transmitted to the particle determination unit 220.

The image converter 210 processes and arranges the distance value information for each detection area in units of frames according to a preset resolution, and generates a distance map of the detection area by matching distance information for each of a plurality of division points. In this case, the image converter 210 arranges the distance value information of the detection area according to the size of N×M divided areas according to a preset resolution. In addition, the image converter 210 arranges the distance values according to the size of an array of n×m pixels set for each divided area, thereby selectively selecting a volume (x,y,z), a distance map, or a height map for each frame. Each can be created. Here, n and m are also natural numbers excluding 0 that are the same or different from each other.

In this way, the image converter 210 includes a volume (x,y,z), a distance map, or a height map for each frame generated using the first and second image sensor units 101 and 103 and the first and second distances. The volume (x, y, z), distance map, or height map for each frame generated using the detection sensor may be mapped to the same resolution, divided by divided regions, and transmitted to the particle determination unit 220.

The particle determination unit 220 divides and stores a distance map or a height map of a detection area mapped from the image converter 210 and input into a plurality of preset N×M areas. In addition, at least one of planar, non-planar, or particle information may be detected by using the average value for each divided area.

Specifically, the particle determination unit 220 reads and stores distance value information for each divided area according to the size of N×M divided areas or a plurality of divided points. Then, by averaging the distance values or height values corresponding to n×m pixels for each of the plurality of divided areas, average value information for each divided area is calculated.

The particle determination unit 220 may average the average value information for each divided area on a per frame basis, calculate a background value for each detection area, and determine whether or not a flat surface is based on the average value for each divided area. The particle determination unit 220 classifies a non-planar divided area by comparing the background value of the divided area with the total average value information, and determines a distance difference value between the divided areas determined to be non-planar. Accordingly, the particle determination unit 220 may determine whether a particle exists in each divided area by comparing the average or background value for each detection area, and the distance values of the non-planar area. The detailed configuration and operation characteristics of the particle determination unit 220 will be described in more detail with reference to the accompanying drawings.

5 is a block diagram showing in detail the constituent elements of the particle determination unit shown in FIG. 3.

The particle determination unit 220 shown in FIG. 5 includes a line analysis unit 221, a line area analysis unit 222, a line determination unit 223, a line distance analysis unit 224, and a particle extraction unit 225. do.

The line analysis unit 221 reads and stores distance value information for each divided area so as to correspond to the size of N×M divided areas or a plurality of divided points, respectively. In this case, the line analysis unit 221 reads and stores depth values corresponding to n×m pixel array sizes so as to correspond to a plurality of division points for each N×M division area. At the same time, depth value information for each of the divided points included in the N×M divided regions is read and stored.

The line area analysis unit 222 calculates average value information for each divided area by calculating an average of distance values corresponding to each of n×m pixels for each of N×M divided areas. The line area analysis unit 222 transmits the average distance value or height value of each of the plurality of divided areas to the line determination unit 223.

The line determination unit 223 calculates the background value of the detection area by averaging the distance or height average value information for each divided area in units of all frames. In addition, it is determined whether or not to be flat for each divided area in comparison with the background value of the detection frame.

The line distance analysis unit 224 determines a height value and a slope of the divided area determined by the line determination unit 223 to be non-planar. Specifically, the line distance analyzer 224 compares the background value of the detection frame with the average value information for each divided area. The non-planar height value and the background value of the divided area determined to be non-planar are compared in units of N×M pixels to detect a distance value or a height value for the divided area determined to be non-planar.

The particle extracting unit 225 compares and analyzes the average distance value for each divided area, the background value of the detection frame, and the non-planar distance value. In addition, particles in the divided areas for which the difference value is calculated are determined based on at least one of the average distance value for each divided area, the background value of the frame, and the non-planar distance value.

FIG. 6 is a diagram illustrating a method of checking distance map information and detecting particles of a particle extracting unit illustrated in FIG. 5.

Referring to FIG. 6, first, the line distance analyzer 224 compares the background value of each of the detection areas DMn+1 with the average value information of each of the divided areas L1 to Ln. In addition, a distance value for the divided regions L and L2 determined to be non-planar is detected by comparing the non-planar distance value of the divided region determined to be non-planar and the background value in units of N×M pixels.

The line distance analysis unit 224 includes average value information for each divided area (L1 to Ln), a distance value corresponding to each of n×m pixels included in each divided area (L, L1), or n×m divisions. You can compare the distance values for each point. Accordingly, if the comparison result of the distance value for each divided area L1 to Ln with respect to the average value is less than a preset reference distance, it may be determined as a plane, and if it is greater than a preset value, it may be determined as a non-planar.

In addition, the particle extracting unit 225 compares the non-planar distance value and the slope for each divided area with a non-planar distance value of at least one other divided area adjacent to each other. In addition, particles in each of the divided regions L1 to Ln may be determined according to a result of the difference compared with each other.

At this time, the particle extraction unit 225 selects at least two divided regions (L, L1) among the plurality of divided regions (L1 to Ln), and sets an average value and a non-planar distance value for the selected two or more divided regions. Can be enlarged in proportion. Accordingly, the particle extracting unit 225 may compare an average value and a non-planar distance value of two or more divided regions that are selectively enlarged with an enlarged non-planar distance value of another divided region. The object and particle extraction unit 225 may more accurately determine the particles in each of the divided regions L1 to Ln according to the result of the enlarged and compared difference.

As described above, the particle detection apparatus of the present invention can detect particles more accurately in real time by analyzing the front and rear imaging results of the semiconductor wafer W to detect particles.

In addition, particle detection by photographing the wafer W in line form using an imaging device such as a line image sensor from the distant side of the rotating wafer W, and calculating the presence of particles through image processing and analysis technology. It is possible to simplify the arrangement structure of the device and increase the space utilization.

As described above with reference to the drawings illustrated for the present invention, the present invention is not limited by the embodiments and drawings disclosed in the present specification, and various by a person skilled in the art within the scope of the technical idea of the present invention. It is obvious that transformations can be made. In addition, even if not explicitly described and described the effects of the configuration of the present invention while describing the embodiments of the present invention, it is natural that the predictable effects of the configuration should also be recognized.

101: first image sensor unit
103: second image sensor unit
111: first imaging module
112: second imaging module
200: particle monitoring device
210: image converter
220: particle determination unit
230: transmission unit

Claims (7)

An imaging module for photographing a partial area of the front or rear surface of the wafer rotating on the exposure chuck or the loading stage for each horizontal line area and extracting distance value information through the captured image data; And
A particle monitoring device that analyzes image data and distance value information captured for each horizontal line area by the imaging module, and sequentially detects particles and sizes of particles for each horizontal line area,
The imaging module
By converting an analog electrical signal according to the intensity of light reflected by the horizontal line area to a digital value and mapping it to a point or coordinate in the image data, digital distance value information according to the intensity of the reflected light is extracted,
The particle monitoring device
A particle detection apparatus for detecting the particles by matching the distance value information for each point in the image data to generate a distance map and a height map according to the distance value information, and analyzing a distance value difference between the distance value information.
The method of claim 1,
The imaging module
By sequentially and continuously photographing the front or rear half portions corresponding to the radius of the rotating wafer by longer horizontal line regions in the horizontal direction, partial image data of the front or rear surfaces of the horizontal line is sequentially output for each frame. Particle detection device.
delete delete The method of claim 1,
The particle monitoring device
Sample distance and height value information included in front or rear image data respectively input through the imaging module,
After filtering and extracting distance and height value information for each frame of the front or rear image data, selectively generating at least one of distance, width, and height maps for each of the horizontal line regions,
A particle detection apparatus for generating at least one of a volume, the distance map, an area, and the height map for each frame by mapping distance and height value information of the image data for each frame according to a plurality of preset blocks or division points.
The method of claim 5,
The particle monitoring device
According to a preset resolution, distance, width, and height value information for adjacent blocks or points are compared with each other, and when the difference between the distance, width and height values is detected above a preset reference, the corresponding horizontal line area or block or point A particle detection device that determines that particles larger than a predetermined size exist at the location of.
The method of claim 5,
The particle monitoring device
Volume, distance, and height value information for the horizontal line area or the blocks are arranged according to a preset resolution, and volume, distance, and height value information of adjacent positions are compared with each other,
By comparing the difference between the volume, distance, and height values with a preset reference value, particles are present in the horizontal line area or block locations where the difference between the compared volume, distance, and height values is greater than or equal to a preset reference value. Particle detection device to judge.

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