JP5439795B2 - Foreign object estimation system - Google Patents

Description

In the present invention, an unexposed colored layer for forming a color filter for a display device disposed on a substrate is attached to the substrate before the transfer mask pattern is transferred and exposed by proximity exposure. The present invention relates to a method for detecting a foreign object and estimating the foreign object.

    FIG. 1 is a cross-sectional view showing an example of a color filter substrate used in a color liquid crystal display device. The color filter substrate 1 has a black matrix (hereinafter referred to as BM) 3 and colored pixels (red R, green G) on a glass substrate 2. , Blue B) (hereinafter referred to as RGB) 4, transparent electrode 5, photo spacer / vertical alignment (hereinafter referred to as PS / VA) 6 are sequentially formed.

  As a method for producing a color filter substrate having the above-described structure used in many color liquid crystal display devices, a photolithography method, a printing method, and an ink jet method are known, and the photolithography method is generally used. FIG. 2 is a schematic block diagram showing the steps of the photolithography method. The color filter substrate is a step of first forming a BM on a glass substrate, a step of cleaning the glass substrate, a step of applying and pre-drying a colored photoresist, a pre-baking step of drying and curing the colored photoresist, and a step of proximity exposure. The step of developing, the step of curing the colored photoresist, the step of forming the transparent electrode, and the step of forming PS / VA are performed in this order. Between the step of cleaning the glass substrate and the step of curing the colored photoresist, the coloring resist is changed for the three colors of red R, green G, and blue B, and the process is repeated three times.

  As described above, there are many steps in the manufacturing process of the color filter substrate, and defects such as dust, resin residue, adhesion / mixing of foreign matters, pinholes, chipped patterns, etc. are generated in the middle of the process.

  The foreign matter may be attached to the color filter substrate and the transfer mask, but when attached to the color filter substrate, not only the color filter substrate itself becomes a defective product but also the color filter substrate. The foreign matter is transferred to the transfer mask and adhered to the transfer mask when the pattern of the transfer mask is transferred and exposed by proximity exposure. The color filter substrate exposed by the transfer mask becomes a defective product having the same defect that occurs continuously.

  In addition, since the exposure gap between the color filter substrate and the transfer mask at the time of the proximity exposure is exposed with a gap close to a contact state, when the foreign matter is a metallic foreign matter having a size larger than the exposure gap. The foreign matter is sandwiched between the transfer mask and the color filter substrate in the exposure machine, causing damage to the transfer mask.

  Since the transfer mask is expensive, the loss due to a single accident is large.

  In order to solve the above-mentioned problem, in the color filter substrate manufacturing process, foreign matter is detected by a detection device before the exposure step to prevent occurrence of the same defect due to foreign matter adhering to the transfer mask, and the transfer mask and the substrate in the exposure machine. A method for preventing the transfer mask from being damaged by the contact of the foreign matter on the top is taken.

However, it is possible to judge the size of a foreign substance as being a foreign substance, but the height of the foreign substance, the metal name if the foreign substance is a metal foreign substance, and the component name if it is an organic or inorganic substance. Since the estimation cannot be determined from the detection result, for example, foreign matter detection is performed before exposure, and when the foreign matter adhesion is recognized, the workpiece is transported to the next step without being exposed, Alternatively, a method is adopted in which the entire surface is exposed without using a transfer mask, and the resist on the entire surface is removed in the next development step (Patent Document 1) .
However, in the above method, every time an adhering foreign matter is detected, the workpiece is conveyed to the next step without being exposed, or the entire surface is exposed without using a transfer mask, and the entire resist is removed in the next developing step. For this reason, there is a drawback that the production efficiency is lowered.

Prior art documents are shown below.
JP-A-11-191524

SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present invention is to provide a system for detecting foreign matter before an exposure process and estimating foreign matter attached to a substrate.

The invention according to claim 1 of the present invention is a system for estimating foreign matter adhering to a substrate, and a foreign matter detection device that detects the detection position (X, Y) and size of the foreign matter and outputs a detection result ; ,
A foreign substance analysis information management database that accumulates information on the foreign substance name , the foreign substance detection position (X, Y), and the detection size as a result of analysis of foreign substances detected in the past as detection result information ;
A foreign substance estimation system, characterized in Rukoto Tokusu preparative estimated foreign substance information by collation with the detection result and the foreign substance analysis information management database obtained by the foreign substance detecting device prior to exposing the substrate.

The invention according to claim 2 of the present invention, before Ki推 compares the constant foreign substance information and the line stop condition, according to claim 1, wherein in the case of satisfying the line stop condition and outputting the warning information This is a foreign matter estimation system.

The invention according to claim 3 of the present invention, the line stop condition is set for each type of foreign matter, the foreign matter estimated according to claim 1 or 2, wherein the previously registered on the foreign substance generation information summary database System.

According to the foreign matter estimation system of the present invention, it is possible to prevent the transfer mask from being damaged by introducing a substrate on which a foreign matter causing damage to the transfer mask is attached to the exposure apparatus. The occurrence of common defects can be prevented.

Hereinafter, the best mode of a foreign matter estimation system according to the present invention will be described with reference to the drawings.

FIG. 3 shows a flow of a schematic configuration device and an estimation system used when estimating the foreign matter adhering to the color filter substrate using the foreign matter estimation system according to the embodiment of the present invention. The color filter substrate 10 is coated with a resist by a resist coating machine 11, the substrate 18 coated with the resist is inspected by a pre-exposure foreign substance detection device 12, and the substrate 19 subjected to the pre-exposure foreign substance inspection is exposed by an exposure machine 13. . The exposed substrate 20 is transferred to the next step. The pre-exposure foreign matter detection device 12 is connected to a foreign matter occurrence status summary database (hereinafter referred to as a foreign matter occurrence status summary DB) 14 and a foreign matter identification system execution personal computer 15 so as to be able to communicate with each other via, for example, Ethernet (registered trademark). The foreign matter estimation system execution personal computer 15 is connected to the foreign matter occurrence status summary DB 14 and the foreign matter analysis information management database (hereinafter, foreign matter analysis information management DB) 16 so as to be able to communicate with each other via, for example, Ethernet (registered trademark). Further, the foreign substance analysis information management DB 16 is connected to the analyzer 17 so as to be able to communicate with each other by, for example, Ethernet (registered trademark).

Foreign matter detection is performed before exposure, and the pre-exposure foreign matter detection device 12 used will be described in detail. FIG. 4A is a schematic diagram of the pre-exposure foreign matter detection device 12. The color filter substrate 18 (the substrate 18 after being coated with the resist in FIG. 3) is illuminated by the specular reflection illumination light source 21 while being conveyed by the conveying device 23, and is captured by the CCD line sensor camera 22, and the captured image is an image processing device. 24. Although not shown, the pre-exposure foreign matter detection device 12 also includes a transmission illumination light source, a reflection illumination light source, and a corresponding line sensor camera. By processing a captured image captured by the line sensor camera, foreign matter detection is performed. Perform detection. The detected position, size and concentration of the detected foreign matter are obtained. The detection position is represented by detection coordinates (X, Y) with a certain point on the color filter substrate 18 as a base point 26 as shown in FIG. The size is obtained from the number of pixels of the light receiving element of the line sensor camera that captured the foreign matter and the size of the foreign matter per pixel, and the density is an analog value obtained from the line sensor camera that captured the foreign matter, for example, 256 levels of digital Obtained by converting to a value. The entire control of the pre-exposure foreign matter detection device 12 is controlled by the control personal computer 25.

A flow for estimating a foreign object will be described with reference to FIG.

  Past foreign matter detection result information is accumulated in the foreign matter occurrence status totalization DB 14, and past analysis result information is accumulated in the following procedure in the foreign matter analysis information management DB 16.

  The foreign matter detected by the pre-exposure foreign matter detection device 12 in FIG. 3 or another foreign matter detection device (not shown) is peeled off from the substrate and analyzed by the off-line analysis device 17, and the foreign matter name and foreign matter generation status based on the analysis result. Are accumulated in the procedure described later and accumulated in the foreign substance analysis information management 16 (S1). The detection result information obtained by the pre-exposure foreign substance detection device 12 is aggregated in a procedure described later, and the aggregated detection result aggregate information is accumulated in the foreign substance occurrence status aggregation DB 14 (S2).

The detection result by the pre-exposure foreign matter detection device 12 is accumulated in the foreign matter occurrence status summary DB 14 as the latest detection result information, and the foreign matter estimation system execution personal computer 15 acquires the latest detection result information (S3). The acquired latest detection result information is collated with the detection result aggregation information stored in the foreign substance occurrence status aggregation DB, and estimated foreign substance information is acquired from the foreign substance analysis information management DB based on the collation result (S4). Further, when the line stop condition is satisfied by comparing the acquired estimated foreign substance information with the line stop condition described later, the determination result and the determination reason are displayed on the monitor of the PC 15 for executing the foreign substance estimation system and the detection device. Display and output warning information to notify the operator (S5), output a stop command to the exposure apparatus according to the operator's judgment and stop the apparatus, or expose the substrate before line exposure or through a mask After that, the resist is removed by a developing device, and the substrate is reused.

  A procedure for collecting analysis result information in the foreign matter analysis information management DB 16 will be described in detail.

  The configuration in the foreign matter analysis information management DB 16 will be described with reference to FIG. In the foreign matter analysis information management DB 16, there are three tables: an analysis result registration table 31, a foreign matter information table 32 for each coordinate, and a foreign matter information table 33 for each area.

  FIG. 6 shows items and descriptions of each table in the foreign substance analysis information management DB 16. The analysis result registration table in FIG. 6A includes the target device, foreign object detection coordinates (X and Y), and foreign object detection mode (whether the detection mode is a regular reflection illumination detection system, a transmission illumination detection system, or a reflection illumination detection system). Distinction), foreign object detection size, foreign name of the analysis result, and date and time of registration of the analysis result. The foreign matter information table for each coordinate in FIG. 6B includes the target device, coordinate (X and Y) conditions, foreign matter detection mode, foreign matter detection size, foreign matter name of the analysis result, and the number of analysis results within the specified period. . The foreign matter information table for each area in FIG. 6C includes the target device, the area condition, the foreign matter detection mode, the foreign matter detection size, the foreign matter name of the analysis result, and the number of analysis results within the specified period.

  A data flow in the foreign matter analysis information management DB will be described with reference to FIG. First, the foreign matter detected by the pre-exposure foreign matter detection device 12 in FIG. 3 or another foreign matter detection device (not shown) is peeled off from the substrate and analyzed by the off-line analysis device 17. The analyzed analysis result information 30 is registered in the analysis result registration table 31 (B1). Next, after the analysis result registration table 31 is updated, the analysis result information is converted into a plurality of conditions of the detection device, detection coordinate X, detection coordinate Y, detection system, and detection size (X coordinate condition & Y coordinate condition & detection system condition & The coordinate-specific foreign matter information table 32 that matches the detected size condition) is updated (B2).

Examples of the plurality of conditions are (1) X coordinate fixed & Y coordinate within a certain range & detection system coincidence & detection size coincidence (2) X coordinate within a certain range & Y coordinate fixed & detection system coincidence & detection size coincidence (3) X coordinate fixed & Y coordinate fixed & detection system coincidence & detection size coincidence (4) X coordinate is within a certain range & Y coordinate is within a certain range & detection system coincidence & detection size coincidence, etc. Totals for all preset conditions By doing so, statistical analysis of foreign matters having a high probability of occurrence is performed for each condition.

  The foreign matter information table for each coordinate indicates what kind of foreign matter has been generated, what kind of foreign matter has been detected in what kind of detection device, and what kind of foreign matter name. Show.

  Next, after the analysis result registration table 31 is similarly updated, the analysis result information is aggregated for each of a plurality of conditions (combinations of conditions of each item) for the detection device, detection area, detection system, and detection size. The foreign object information table 33 is updated (B3).

Examples of the plurality of conditions include
(1) Detection area fixed & detection system coincidence & detection size coincidence (2) Detection area is specified area (s) & detection system coincidence & detection size coincidence, etc. Perform analysis.

  In the foreign matter information table for each area, what kind of defect is detected, what kind of defect is detected in what area, what kind of defect, and the name of the foreign matter. Show.

  The configuration in the foreign matter occurrence status summary DB 14 will be described with reference to FIG. The foreign matter occurrence status totalization DB 14 includes four tables, a foreign matter detection result registration table 41, a foreign matter detection information table 42 for each coordinate, a foreign matter detection information table 43 for each area, and a line stop condition table 45.

FIG. 8 shows items and descriptions of each table in the foreign matter occurrence status totalization DB 14. The foreign object detection result registration table in FIG. 8A includes the target device, the inspected substrate identification code, the foreign object detection area, the foreign object detection coordinates (X and Y), the foreign object detection mode, and the foreign object detection size. The foreign substance detection information table for each coordinate in FIG. 8B includes the target device, the coordinate conditions (X and Y), the foreign substance detection mode, the foreign substance detection size, the total result of the foreign substance detection, and the detection density condition (the density is the detected foreign substance. The analog value of the captured image is converted into, for example, a 256-level digital value). The foreign matter detection information table for each area in FIG. 8C includes the target device, area conditions, foreign matter detection mode, foreign matter detection size, and foreign matter detection tabulation results. The line stop condition table in FIG. 8D includes the target device, the foreign object detection mode, the foreign object detection size, the estimated foreign object name, and the line stop condition.

  A data flow in the foreign matter occurrence status summary DB 14 will be described with reference to FIG. First, the detection result information 40 obtained from the pre-exposure foreign matter detection device 12 of FIG. 3 is registered in the foreign matter detection result registration table 41 (K1). After the data in the foreign object detection result registration table 41 is updated, a plurality of conditions (X coordinate condition & Y coordinate condition) of the detection device, detection coordinate X, detection coordinate Y, detection system, detection size, and detection density in the foreign object detection result registration table & Foreign substance detection information table 42 for each coordinate coordinate is updated under (& detection system condition & detection size condition & detection density condition) (K2).

Examples of the plurality of conditions are (1) X coordinate fixed & Y coordinate within a certain range & detection system coincidence & detection size coincidence & detection density within a certain range.
(2) X coordinate is within a certain range & Y coordinate fixed & detection system coincidence & detection size coincidence & detection density is within a certain range.
(3) X coordinate fixed & Y coordinate fixed & detection system coincidence & detection size coincidence & detection density is within a certain range. (4) X coordinate is within a certain range & Y coordinate is within a certain range & detection system coincidence & detection size coincidence & detection density is within a certain range.
By performing aggregation for all preset conditions, a statistical analysis of foreign matters having a high probability of occurrence is performed for each condition.

  The foreign matter detection information table for each coordinate indicates at what coordinates, how detected, what size, and what kind of density defects.

  Next, after the data in the foreign object detection result registration table 41 is updated, the foreign object detection result registration table is aggregated for each of a plurality of conditions (combinations of conditions of each item) for the detection device, detection area, detection system, and detection size. Then, the foreign matter detection information table 43 for each area is updated (K3).

Examples of the plurality of conditions include
(1) Detection area fixation & detection system coincidence & detection size coincidence.
(2) The detection area is the designated area (s) & detection system match & detection size match.
The statistical analysis of foreign matters having a high probability of occurrence in each area combination is performed.

  The foreign matter detection information table for each area indicates in which area, how detected, what size defect is frequently generated.

Next, the foreign substance estimation process described later is performed from the foreign substance analysis information management DB 16.

  A line stop condition 44 is set in advance for each type of foreign matter, and the set line stop condition is registered in the line stop condition table 45 (K4).

FIG. 9 is a diagram showing a flow of foreign object estimation processing. The foreign object estimation process is performed according to the following flow. First, after the foreign matter is detected by the pre-exposure foreign matter detection device 12 and the substrate is paid out, the detection result information of the substrate is registered in the foreign matter detection result registration table 41 as the latest detection result information (D1). The foreign substance estimation system execution personal computer 15 acquires foreign substance detection coordinate (X, Y), detection system, and detection size information from the latest detection result information in the foreign substance detection result registration table 41 (D2), and coordinates based on it. From the foreign object detection information table 42, a combination of conditions including detection coordinates and a combination having a high detection system and detection size occurrence probability is acquired. In addition, an inquiry condition to the foreign object information table for each coordinate, that is, a foreign object for each coordinate. When the detection information table is created, for example, a condition that the X coordinate & Y coordinate is within a certain range & detection system coincidence & detection size coincidence & detection density is within a certain range is determined here (D3). Furthermore, information on the detection area, detection system, and detection size of the foreign matter is acquired from the latest detection result information, and based on the information, acquired from the results collected for the conditions including the detection area from the foreign matter detection information table 43 for each area. Detection system, a combination that has a high probability of occurrence of detection size, and the inquiry condition to the foreign matter information table for each area, that is, when the foreign matter detection information table for each area is created, for example, detection area fixation & detection system matching & Condition such as detection size coincidence is determined here (D4). Under the inquiry condition determined in (D3), foreign matter information having a high occurrence rate is acquired in the foreign matter information table 32 for each coordinate (D5), and in the inquiry condition determined in (D4), the occurrence rate is entered in the foreign matter information table 33 for each area. High foreign matter information is acquired (D6). Each of the foreign matter name obtained based on the estimated foreign substance information as an estimated foreign substance information (D5) and (D6), to obtain the line condition for stopping the estimated foreign object (D7).

In the estimated foreign object information, one foreign object name is not necessarily estimated , and a plurality of foreign object names may be estimated . Therefore, when there are a plurality of foreign substance names acquired in (D5) and (D6), line stop conditions corresponding to the plurality of foreign substance names are acquired.

The line stop condition varies depending on the type of foreign matter. For example ,
(1) Anomaly determination for 5 consecutive images (2) Anomaly determination if the number of foreign objects in the periphery (arbitrarily set peripheral area) is A (A is an arbitrary number) or more (3) Peripheral coordinates (arbitrarily set The line stop condition is a case where abnormality is determined when B (B is an arbitrary number) continuous occurrences in peripheral coordinates), and is registered in the line stop condition table 45 in advance for each type of foreign matter.

After acquiring the line stop condition, the estimated foreign matter information is compared with the line stop condition, and if the line stop condition is satisfied, it is determined that the line is stopped.

If it is determined that the line is stopped, alarm information is output (D8). Simultaneously with the alarm information output, the determination result and the determination reason are displayed on the monitor of the personal computer 15 for executing the foreign substance estimation system and on the detection device, and the stop information is output to the exposure apparatus by the operator's judgment by outputting the warning information. The substrate is lined out before exposure or exposed without passing through a mask, and then the resist is peeled off by a developing device, and the substrate is reused.

As described above, according to the foreign matter estimation system of the present invention, it is possible to prevent the transfer mask from being put into the exposure machine because the foreign matter that causes the damage to the transfer mask can be prevented. Furthermore, the occurrence of common defects due to foreign matters can be prevented.

The figure which showed an example of the color filter board | substrate in the cross section. The schematic block diagram which shows the process of the photolithographic method. Foreign matter according to embodiments of the present inventionEstimatedUse the system to remove foreign matter adhering to the color filter substrate.EstimatedA schematic configuration device used in the case ofEstimatedSystem flow The theoryThe figure to light. (A) is the schematic of a pre-exposure detector. (B) is a diagram showing detected coordinates (X, Y). The figure which shows the structure in the foreign material analysis information management DB concerning embodiment of this invention. FIG. 5 is a diagram showing definitions of each table in the foreign matter analysis information management DB according to the embodiment of the present invention. (A) is an analysis result registration table, (b) is a foreign matter information table for each coordinate, and (c) is a foreign matter information table for each area. . The figure which shows the structure in the foreign material generation condition totalization DB concerning embodiment of this invention. FIG. 5 is a diagram showing definitions of each table in the foreign matter occurrence status summary DB according to the embodiment of the present invention. (A) is a foreign matter detection result registration table, (b) is a foreign matter detection information table for each coordinate, and (c) is foreign matter detection information for each area. Table (d) shows a line stop condition table. The figure which shows the flow of the foreign material estimation process concerning embodiment of this invention.

DESCRIPTION OF SYMBOLS 1 ... Color filter substrate 2 ... Glass substrate 3 ... Black matrix (BM)
4 ... Colored pixels (RGB)
5 ... Transparent electrode 6 ... Photospacer / Vertical alignment (PS / VA)
DESCRIPTION OF SYMBOLS 10 ... Color filter substrate 11 ... Resist coating machine 12 ... Pre-exposure foreign matter detection device 13 ... Exposure machine 14 ... Foreign matter generation status totalization DB
15 ... PC for executing foreign matter estimation system 16 ... Foreign matter analysis information management DB
DESCRIPTION OF SYMBOLS 17 ... Analyzing device 18 ... Substrate coated with resist 19 ... Substrate subjected to foreign matter inspection before exposure 20 ... Exposed substrate 21 ... Regular reflection illumination light source 22 ... Line sensor camera 23 ... Conveying device 24 ... Image processing device 25 ... Control personal computer for foreign matter detection device 26 before exposure 26 ... Base point (a place on the color filter substrate)
30 ... Analysis result information 31 ... Analysis result registration table 32 ... Foreign matter information table for each coordinate 33 ... Foreign matter information table for each area 40 ... Detection result information 41 ... Foreign matter detection result registration table 42 ... Foreign matter detection information table for each coordinate 43 ... Foreign matter detection information table for each area 44 ... Line stop condition 45 ... Line stop condition table

Claims (3)

A system for estimating foreign matter adhering to a substrate,
A foreign object detection device that detects the detection position (X, Y) and size of the foreign object and outputs a detection result ;
A foreign substance analysis information management database that accumulates information on the foreign substance name , the foreign substance detection position (X, Y), and the detection size as a result of analysis of foreign substances detected in the past as detection result information ;
Foreign matter estimation system, characterized in Rukoto Tokusu preparative estimated foreign substance information by collation with the detection result and the foreign substance analysis information management database obtained by the foreign substance detecting device prior to exposing the substrate.
Before Ki推 compares the constant foreign substance information and the line stop condition, the foreign matter estimation system according to claim 1, wherein outputting the alert information if satisfying line stop condition. The foreign matter estimation system according to claim 1 or 2, wherein the line stop condition is set for each kind of foreign matter and is registered in advance in the foreign matter occurrence information aggregation database.

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