KR20050102324A - Particle detector system and method of thin film forming process - Google Patents

Abstract

The present invention relates to a foreign matter detection device and method for detecting foreign matter particles present on the surface of an object for precision coating or fine plate attachment in a thin sheet forming process to precisely inspect a cleaning state.

A plurality of optical particle sensors are installed on the upper surface of the screen on which the work object is aligned, and are disposed in a plurality of optical particle sensors for detecting the presence of foreign matter particles through the intensity for each wavelength of the reflected light after being focused in the width direction of the work object. It provides a foreign matter detection device, characterized in that installed in the form of a line having a right angle or a predetermined inclination angle with respect to the direction.

In addition, when the workpiece is placed and aligned on the screen, the optical foreign matter sensor generates light and irradiates the light, and extracts two lights from the irradiated light and irradiates the fixed positions on the workpiece. Separating the light reflected from the work object into the two extracted light, extracting the sensitivity by dividing the wavelength of the two reflected light, and determining the sensitivity of the wavelength to the extracted two light. The process of comparing with the reference value set by the calculation, the process of determining whether there is foreign matter particles on the surface of the workpiece according to the comparison result, and if it is determined that the foreign matter particles are present, the information is displayed on the peripheral device to be linked This includes providing the information.

Therefore, the loss of expensive work objects does not occur in sheet metal forming work, and by transmitting the corresponding information to the interlocking peripheral device to take appropriate measures, it is possible to reduce the damage of expensive equipment and significantly reduce the defective rate of the board. There is an effect that can be reduced.

Description

Particle Detector System And Method Of Thin Film Forming Process

The present invention relates to an apparatus for detecting a foreign matter in the sheet forming process, and more particularly to detect the particles present on the surface of the work object for the precision coating operation or the micro thin plate attachment operation to precisely inspect the cleaning state. It relates to a foreign matter detection apparatus and method.

In general, a thin plate forming process is to attach a fine coating film or a fine thin plate to a glass (LCD) of a flat panel display panel, a PDP panel having a lattice arrangement, a battery coil, or the like by using a phosphor coating liquid discharge device or a film attachment device. When a fine coating operation or a fine thin plate attachment operation is performed in a state in which foreign matter is present on the surface of the surface, damage of an expensive coating liquid discharge device or a film attachment device is caused, and an expensive work object is poorly processed.

Therefore, precise cleaning is performed in the process of inserting the work object into the sheet forming process, but foreign matter may be adsorbed on the surface of the work object under the influence of various conditions, so that the coating liquid ejecting device or the film attaching device is transported. On the side is arranged an apparatus for detecting foreign matter which may be present on the substrate.

Conventional foreign matter detection device is provided with a light source for generating infrared light on one side of the screen to align the work object, and an optical sensor for receiving the infrared light generated by the light source on the other side correspondingly, the light source The sensitivity of the light between the light sensor and the light sensor detects the presence of foreign matter on the surface of the workpiece.

However, the foreign matter detection device as described above is a case where the foreign matter adsorbed on the surface of the work object is close to the light source or the light sensor, and is separated from the light source or the light sensor by more than a certain distance, that is, the sensitivity of the light according to the distance. Since it is not uniform due to the diffraction phenomenon due to the collision with the foreign matter particles, there is a disadvantage that the reliability in the detection of the foreign matter is lowered, thereby securing the stability of the operation.

The present invention has been proposed to solve the above problems, the object of which is to install a line CCD (Charged Coupled Device) including an optical system at a predetermined position on the surface of the workpiece in the sheet forming process, the surface of the workpiece It is possible to perform precise coating work or micro thin film attachment work by measuring and detecting the surface of the work object by fixing the focus of a light source having a different wavelength (frequency spectrum) at a position corresponding to the height of the foreign matter particles adsorbed and the detection area height. It is to be able to accurately detect the size and thickness of the fine foreign particles present on the surface of the work object.

In addition, by detecting the fine foreign particles adsorbed on the surface of the work object to protect the operation of the work tool, such as phosphor coating liquid discharge device or film attachment device, to prevent the deterioration of the coating film quality due to the adsorption of foreign matter particles, The cleaning status of the product and the inspection of the product are to be performed at the same time.

Further, by arranging a plurality of line CCDs, high speed and precision are provided to detect whether or not foreign matter particles P adsorb on the surface of the workpiece.

In order to achieve the above object, the present invention provides a focal length different in accordance with the wavelength of the light reflected from the foreign matter particles in the width direction of the workpiece is installed in the upper surface of the screen, the workpiece is aligned in the sheet forming process It is provided with a plurality of optical particle sensor for detecting the presence of foreign matter particles by having a foreign matter detection apparatus, characterized in that installed in the form of a line having a right angle or a predetermined inclination angle with respect to the conveying direction.

The present invention is a thin plate forming process, when the workpiece is put on the screen and aligned, the optical particle sensor generates light and irradiates; Irradiating two lights having a specific wavelength in the irradiated light to respective fixed positions on a workpiece; Separating the light reflected from the work object into two lights; Extracting sensitivity by detecting wavelengths of the two reflected light beams; Calculating a sensitivity of the wavelengths of the two extracted light beams and comparing them with a set reference value; Determining whether foreign matter exists on the surface of the workpiece according to the comparison result; When it is determined that the foreign matter exists, the present invention provides a foreign matter detection method comprising displaying information on the same and providing the corresponding information to the peripheral device to be interlocked.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a schematic perspective view for explaining an embodiment according to the present invention, Figure 2 is a conceptual view showing a part cut in the transport direction of the workpiece with respect to Figure 1, the workpiece (G), the work The foreign substance detection apparatus 100 arrange | positioned at one surface (upper part) of the object G is shown.

The foreign matter detection device 100 is configured to detect the presence or absence of foreign matter particles (P; also referred to as particles) adsorbed on the surface of the work object G and the size and thickness of the foreign matter particles. A plurality of optical particle sensors 103 are arranged at regular intervals in the width direction of and are installed in a line shape having a right angle or a predetermined inclination angle with respect to the conveying direction.

Therefore, the foreign matter detection device 100 having a line shape can accurately detect the foreign matter particles P that may exist in the entire region of the surface of the work object G in the transported state.

The optical particle sensor 103 irradiates two pieces of light having different wavelengths (spectrums) and irradiates the light with a set upper and lower limits, and the two pieces of irradiated light are provided on the surface of the work object G. It consists of a part that receives the light reflected by the foreign matter particles (P) and the sensitivity of the wavelength (spectrum) for the two received light to determine the presence of the foreign matter particles (P) and the size and thickness of the particles. .

In FIG. 1, the solid arrow indicates the direction in which the work object G is moved or the direction in which the foreign matter detection device of the present invention is moved. In the description of the present invention, the foreign matter detection device 100 is conveyed for convenience. An example will be described.

The structure and principle of the optical particle sensor 103 constituting the foreign matter detection device 100 will be described in more detail with reference to FIGS. 3 to 5.

The optical particle sensor 103 focuses the light irradiating means 120 for irradiating light, preferably a light source (laser) of two wavelengths, and the light irradiated from the light irradiating means 120 to the work object G. In accordance with the light focusing means 140 for fixing the focus at the adjusted position of the beam splitter 160 to change the direction of the light reflected from the surface of the workpiece (G), and the direction of the beam splitter 160 It may be provided with a detection means 180 for detecting the wavelength (spectrum) of the light to be detected.

The detection unit 180 senses the sensitivity of the detected light, calculates a sensitivity difference value of the sensed wavelength, and calculates a difference value of the detected wavelength from the difference in the focal length according to the wavelength (spectrum). ) And transmits the detected value to the controller (C) which determines whether the foreign matter particles (P) size and thickness.

The light irradiating means 120 includes a light source LS provided to a case (not shown), a lens assembly 121 for collecting light emitted from the light source LS, and light collected from the lens assembly 121. The light passing member 123 passing the slit 123a of a predetermined length, and the first filter 125 further narrowing the line width with respect to two desired wavelengths (spectrum) in the light passing through the light passing member 123. It includes.

The light source LS may irradiate a laser or an LED, and a conventional one may be used.

The light passing member 123 is disposed at the focal position of the lens assembly 121 and is preferably disposed at a position through which the light of the light source LS passes through the slit 123a as the strongest light.

In particular, the slit 123a provided in the light passing member 123 may be formed of a long hole having a long shape so as to have a vertical or constant inclination with respect to the traveling direction of the work object G.

The first filter 125 serves to filter out unnecessary light in addition to light having two groups of wavelengths (spectrum).

The light converging means 140 may be formed of a lens assembly in which a focal length may vary according to a wavelength (spectrum) due to chromatic aberration.

The light converging means 140 is a focal point A of a first wavelength (spectrum) in which the focal point is formed at an upper end (fixed first position) of the work object G, and is actually a group of wavelengths of a specific region. And the focal point B of the second wavelength (spectrum) formed on a position (fixed second position) at a predetermined distance from the work object G. It is a group, and for convenience, it can be divided into one wavelength).

The light focusing unit 140 may be a zone plate or a panel lens.

On the other hand, the beam splitter 160 is disposed between the light irradiation means 120 and the light focusing means 140 to pass the light of the light source (LS), the light through the light focusing means 140 to work It serves to change the direction so that the light reflected from the object (G) is irradiated to the detection means 180 side.

The detection means 180 is another light passing member 181 having a slit through which the light irradiated by being turned by the beam splitter 160 can pass therethrough, and the light passing through the light passing member 181. Another lens splitter 183 which can be collected, another beam splitter 185 which passes the light passing through the lens assembly 183 according to the respective wavelengths or reflects at a predetermined angle and divides it into two positions, the beam splitter The second filter 187 and the beam provided to the detection means 180 filter the wavelength of the band acting as noise in the light passed by 185 to pass only one wavelength selected by the light irradiation means 120. A third filter 189 for filtering only the wavelength of the band acting as noise in the light reflected by the splitter 185 and passing only another wavelength selected by the light irradiation means 120, and the second and third filters ( 187, 189) It may include first and second image sensing device (191, 193) for sensing light.

The light passing member 181 provided to the detection unit 180 may pass the light having the most focused wavelength among the wavelengths of the light reflected by the beam splitter 160 at the strongest intensity.

In addition, the lens assembly 183 provided to the detecting means 180 collects light and serves to pass or reflect a specific wavelength in the beam splitter 185 provided to the detecting means 180.

The controller C calculates the sensitivity of the two wavelengths (spectrum) detected by the work object G with a set algorithm, and foreign matter particles P exist on the surface of the work object G by analyzing the calculated result. And the size and thickness of the foreign matter particles (P).

The controller (C) is provided with a display means to display information on the foreign matter particles (P) detected, that is, the presence or absence of the foreign matter particles (P) and information on the thickness and size of the foreign matter particles (P).

In the memory unit (not shown) of the controller C, the first and second imaging devices 191 and 193 may be connected to each other according to the size and thickness of the foreign matter particles G present on the surface of the work object G. The reference data obtained by learning the sensitivity of the two wavelengths detected as described above is stored as a value of a one-dimensional curve that is linearized as shown in FIG. 5.

In addition, the controller C provides the corresponding information to the phosphor coating liquid ejecting device or the film attaching device, which is a peripheral device that is interlocked when the presence of the foreign matter particles P is detected on the surface of the work object G, thereby providing foreign matter particles. Ensure that the appropriate response to the presence of (P) can be performed.

The controller C includes a differential amplifier and an A / D conversion means, and differentials the sensitivity of two wavelengths detected by the first and second image pickup devices 191 and 193 in the detection means 180 using a differential amplifier. Alternatively, by extracting the sensitivity between the two wavelengths as a one-dimensional function by calculating the difference, and converts the extracted function value into a digital signal through the A / D conversion means, by applying the comparison to the reference data of Figure 5 to extract the depth of the wavelength To extract the presence or absence of foreign matter particles (P) and the size and thickness of the foreign matter particles (P).

The operation of detecting whether foreign matter particles P are present on the surface of the work object G through the foreign matter detector 100 applicable to the present invention as described above will be described in detail with reference to FIG. 6.

When the work object G, which has been cleaned, is put into a thin plate forming process and alignment is completed on the screen, light irradiation means of the plurality of optical particle sensors 103 constituting the foreign matter detection device 100 according to the present invention ( The light source LS in 120 generates light having two wavelengths and irradiates the work object G aligned on the screen (S101).

Light having two wavelengths generated by the light source LS is focused by the lens assembly 121 and passes through the slit 123a of the light passing member 123 and then passes through the first filter 124.

At this time, the first filter 125 filters only the light of the light source LS and passes through only the light having two narrow line widths (spectrums) and irradiates the light focusing unit 140 (S102).

The optical focusing unit 140 has a focal point A at a fixed first position of the workpiece G with respect to the two wavelengths (spectrum) due to chromatic aberration using the lens assembly. The other wavelength (spectrum) causes the focus B to be fixed to the second fixed position on the work object G (S103).

The light irradiated to focus on the fixed first position and the second position on the work object G as described above is reflected from the surface of the work object G, and the reflected light travels by the beam splitter 160. The direction is switched and irradiated to the detection means 180 side.

At this time, the light passing member 181 in the detecting means 180 passes through the light irradiated by the beam splitter 160 and is focused through the lens assembly 183 and then through the beam splitter 185. Passing the reflected light according to the wavelength or by reflecting at a predetermined angle is separated into two lights (S104).

Among the lights separated by the beam splitter 185 in the detection unit 180 as described above, one light is filtered by the second filter 187 to filter out the noise band included in the transmission process. ) Is transmitted to the controller (C), and the other light is filtered by the third filter (189) and the noise band included in the transmission process is input to the second image pickup device (193) to the controller (C). Is sent.

The controller C detects the sensitivity of the wavelength to the two light beams from the work object G input from the first image pickup device 191 and the second image pickup device 193 (S105). Differential amplifiers (B = S2 / S1) or differential calculations (B = S2-S1) are used to extract the sensitivity between two wavelengths as a one-dimensional function (S106).

Thereafter, the extracted function value is converted into a digital signal through the A / D conversion means, and applied to the reference data of FIG. 5 to compare and extract the corresponding wavelength (S107), from which the light irradiation means 120 is irradiated. By extracting the depth information on the wavelength of light, it is to extract the presence or absence of foreign matter particles (P) on the surface of the workpiece (G) (S108).

In the case of the light irradiated to the respective positions fixed on the surface of the object (G) in the light irradiation means 120 in the case where the focus is precisely at the fixed position, the sensitivity of the wavelength detected by the controller C is the strongest If the focus is not precisely set at a fixed position due to the presence of foreign matter particles P on the surface of the work object G, it is reflected as scattered from the surface of the foreign matter particles P and is reflected to the controller C. The sensitivity of the detected wavelength is detected with a sensitivity lower than the strongest value.

Accordingly, the controller C extracts the difference in sensitivity as a first-order function by differentially or differentially calculating the sensitivity of the two lights detected as described above, and compares it with the reference data of FIG. 5 stored in the memory means. The presence or absence of the foreign matter particles P in the work object G can be detected.

Information on the presence or absence of foreign matter particles (P) on the surface of the work object (G) extracted as described above is displayed through the display means (S109), foreign matter particles (P) on the surface of the work object (G) When it is detected that the corresponding information is provided to the phosphor coating liquid ejecting device or the film attaching device, which is the peripheral device to be interlocked, so that the appropriate response according to the presence of the foreign matter particles (P) can be performed (S110).

In the description of the above example, the workpiece is an example for the flat panel display, but the method of applying the same to the battery coil for applying the electrode material, as shown in FIG. 6, is also included in the scope of the present invention. As shown in the drawing, a method applied in a molding process of applying a phosphor film to a lattice arrangement of glass of a plasma display panel is also included in the scope of the present invention, which can be easily carried out by those skilled in the art as in the above-described embodiments. Description is omitted.

As described above, the present invention can quickly and reliably detect whether or not foreign particles exist on the surface of the workpiece to be aligned on the screen in the sheet forming process, so that expensive workpieces are not lost in the sheet forming operation. The reliability and stability of the work is provided.

In addition, if foreign matter particles are detected on the surface of the workpiece, appropriate information can be taken by transmitting the information to the peripheral device to be interlocked, thereby reducing damage to expensive equipment and significantly reducing the defective rate of the substrate. It can be effective.

In addition, by detecting the size and thickness of the foreign matter particles present on the surface of the workpiece, the accuracy in the cleaning process can be confirmed.

1 is a perspective view schematically showing a foreign matter detection apparatus in a thin plate forming process for explaining an embodiment according to the present invention.

FIG. 2 is a cross-sectional view schematically illustrating the cut portion A-A of FIG. 1.

Figure 3 is a detailed configuration of the foreign matter detection apparatus in the sheet forming process according to an embodiment of the present invention.

4 to 5 are graphs for explaining the operation principle of the sensor that can be applied to the present invention.

6 to 7 are cross-sectional views showing another application example of the foreign matter detection apparatus in the sheet forming process according to an embodiment of the present invention.

8 is a flow chart for performing foreign material detection in the sheet forming process according to an embodiment of the present invention.

Claims (20)

In the sheet forming process, A plurality of optical particle sensors are installed on the upper surface of the screen on which the workpiece is aligned and detect the presence of foreign particles by having different focal lengths depending on the wavelength of light reflected from the foreign particles in the width direction of the workpiece. The foreign matter detection device in the thin plate forming process, characterized in that disposed in the form of a line having a right angle or a predetermined inclination angle with respect to the conveying direction. The method of claim 1, The optical particle sensor may include light irradiation means for generating light and irradiating separately into light having different wavelengths; Light focusing means for focusing the light irradiated from the light irradiation means to fix the focus at each adjusted position of the workpiece; A beam splitter disposed between the light irradiating means and the light converging means to change the direction of light reflected from the surface of the workpiece; And detecting means for receiving a wavelength of light detected in accordance with the change of direction of the beam splitter. The method of claim 1, The controller for sensing the sensitivity of the wavelength of the light reflected from the surface of the workpiece, and calculates the sensitivity difference value of the sensed wavelength to determine whether there is foreign particles on the surface of the workpiece from the difference in the focal length according to the wavelength The foreign material detection apparatus in the thin plate forming process, characterized in that it further comprises. The method of claim 2, The light irradiation means is a light source; A lens assembly collecting light emitted from the light source; A light passing member disposed at a focal point of the lens assembly and configured to pass the collected light through a slit having a predetermined length; And a first filter for passing the light passing through the light passing member at a narrow line width with respect to two desired wavelengths in the light passing through the light passing member. The method of claim 4, wherein  The slit provided in the light passing member is a foreign matter detection device in the thin plate forming process, characterized in that it consists of an elongated long hole to have a vertical or constant inclination with respect to the traveling direction of the workpiece. The method of claim 2, The optical focusing means is a foreign matter detection device in a thin plate forming process, characterized in that the focal length can be changed by the lens assembly by the chromatic aberration. The method of claim 2, The light focusing means focuses on the first position on the workpiece with respect to the wavelength having one group, and focuses on the second position spaced apart from the workpiece with respect to the wavelength having the other group. A foreign matter detection device in a thin plate forming process. The method of claim 2, The optical focusing means is a foreign matter detection device in a thin plate forming process, characterized in that the use of a zone plate or a panel lens. The method of claim 2, The detecting means includes a light passing member provided with a slit through which the light irradiated by the direction is passed; A lens assembly for focusing light passing through the light passing member; A beam splitter which separates each wavelength by passing the light passing through the lens assembly according to each wavelength or reflecting at a predetermined angle; A second filter for filtering a wavelength of a band acting as noise in the light passed by the beam splitter and passing only one wavelength selected by the light irradiation means; A third filter for filtering a wavelength of a band acting as noise in the light passed by the beam splitter and passing only another wavelength selected by the light irradiation means; And a first and second imaging device configured to sense light passing through the second filter and the third filter. The method of claim 9, The light passing member is a foreign matter detection device in the thin plate forming process, characterized in that for passing the light having the most focused wavelength among the wavelengths of light reflected by the beam splitter. The method of claim 3, The controller calculates the sensitivity of the two wavelengths detected in the workpiece by a set algorithm, and detects the foreign substance in the sheet forming process, characterized in that whether foreign particles are present on the surface of the workpiece by analyzing the calculated results. Device. The method of claim 3, The controller has a foreign matter detection device in a thin sheet forming process, characterized in that the display means for displaying the presence of foreign matter particles and the thickness and size information of the foreign matter particles. The method of claim 3, The controller stores the reference data obtained by learning sensitivity for the two wavelengths detected according to the size and thickness of foreign matter particles present on the surface of the work object as a value of a linearized one-dimensional curve. Foreign material detection device in the sheet forming process. The method of claim 3, When the controller detects the presence of foreign matter particles on the surface of the work object, the controller provides corresponding information to a peripheral device to be interlocked so that appropriate response according to the presence of foreign matter particles can be performed. Detection device. The method of claim 3, The controller includes a differential amplifier and an A / D conversion means, differentially calculates the sensitivity of the detected two wavelengths using a differential amplifier, extracts the sensitivity between the two wavelengths as a one-dimensional function, and extracts the extracted function value from the A / D. A foreign matter detection device in a thin sheet forming process, characterized in that the presence and size and thickness of foreign matter particles are extracted by detecting the depth of the wavelength by converting the digital signal through the conversion means and comparing with the reference data. The method of claim 3, The controller includes a differential amplifier and an A / D conversion means, and differentially calculates the sensitivity of the detected two wavelengths using a differential amplifier to extract the sensitivity between the two wavelengths as a one-dimensional function, and extracts the extracted function value from the A / D. A foreign matter detection device in a thin sheet forming process, characterized in that the presence and size and thickness of foreign matter particles are extracted by detecting the depth of the wavelength by converting the digital signal through the conversion means and comparing with the reference data. In the sheet forming process, When the workpiece is input and aligned on the screen, the optical particle sensor generates and irradiates light; Irradiating two lights from the irradiated light to respective fixed positions on the workpiece; Separating the light reflected from the work object into the extracted two lights; Extracting sensitivity by detecting wavelengths of the two reflected light beams; Calculating a sensitivity of the extracted two lights and comparing them with a set reference value; Determining whether foreign matter particles are present on the surface of the workpiece according to the comparison result; The foreign matter detection method in the thin plate forming process comprising the step of providing information to the peripheral device interlocked with the information displayed when it is determined that the foreign matter particles are present. The method of claim 17, Irradiation for focusing the two light extracted from the light source to each fixed position on the work object using a chromatic aberration of the wavelength, the foreign material detection method in the thin sheet forming process. The method of claim 17, The foreign matter detection method in the sheet forming process, characterized in that the calculation of the sensitivity for the two wavelengths of the reflection detection is extracted as a one-dimensional function value by a difference operation using a differential amplifier. The method of claim 17, The foreign matter detection method in the thin sheet forming process, characterized in that it is determined that the foreign matter particles do not exist on the surface of the workpiece when the sensitivity value calculated by the two reflected wavelengths is not included in the measurement range of the set reference data.