JP2005031496A - Exposure device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an exposure apparatus for inspecting an exposure mask to be used for a flat display, speedily and at a low cost. <P>SOLUTION: The inspection time is reduced by dividing the inspection area of an exposure mask 2 into reading areas 7a, 7b and separately reading out by a plurality of optical reading devices 5a, 5b, and by processing the difference between the read result of the optical reading devices 5a, 5b and the predetermined referential data by an inspection processing device 6 so as to judge whether a defect is present or not. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an exposure apparatus used when a pattern such as an electrode is formed on a flat substrate used for a relatively large flat display such as a plasma display panel.

  In the flat display manufacturing process, a photosensitive resin layer is formed on a flat substrate, and the photosensitive resin layer is exposed through an exposure mask on which a pattern such as an electrode is formed. After exposure, development and etching are performed. In general, a target pattern is formed on the flat substrate.

Here, when the exposure mask has a defect such as a foreign substance or a scratch, the defect is transferred to the exposure pattern. Therefore, it is necessary to detect the defect and remove the defect before exposure.
(Patent Document 1) discloses an exposure mask that is not a flat display manufacturing process but is used in a semiconductor element manufacturing process by comparing the pattern image of the exposed exposure mask after cleaning with a reference for residual pattern defects. A technique for automatically detecting a defect remaining in a mask and re-cleaning is described.

Further, (Patent Document 2) describes an exposure apparatus having a function capable of detecting an exposure mask defect.
Japanese Patent Publication No. 4-5978 JP-A-5-41341

  The size of an exposure mask used in a conventional semiconductor device manufacturing process is 230 mm × 230 mm (in the case of 9 inches), whereas the size of an exposure mask used in a flat display is 1000 mm × 600 mm (42 inches). Case) and the exposure mask used in the semiconductor device manufacturing process are orders of magnitude larger.

  Therefore, if the exposure mask used for the flat display is inspected while scanning according to the procedure performed in the defect inspection of the exposure mask used in the manufacturing process of the semiconductor element, there is a problem that the inspection time becomes long. is there.

  To avoid this, create a special optical sensor with a reading surface of the same size as the exposure mask, place the exposure mask on it, and simultaneously inspect the inspection light transmitted through the exposure mask for inspection. It is conceivable to do this, but the cost is high and the present situation is lacking in feasibility.

  An object of the present invention is to provide an exposure apparatus capable of quickly inspecting an exposure mask used for a flat display at a low cost.

  In order to solve this problem, an exposure apparatus of the present invention is characterized in that a defect inspection area of an exposure mask arranged at an exposure position is divided into a plurality of areas and is divided into each area and inspected simultaneously.

  An exposure apparatus according to claim 1 of the present invention is an exposure apparatus that performs exposure through an exposure mask having a pattern formed on a flat substrate, and divides the exposure mask arranged at an exposure position into a plurality of areas. A plurality of optical readers for each inspection, and an inspection processor for performing a difference process between a result read by the plurality of optical readers and predetermined reference data to determine the presence or absence of a defect in the exposure mask. It is characterized by that.

An exposure apparatus according to a second aspect of the present invention is the exposure apparatus according to the first aspect, wherein at least a part of the plurality of areas overlaps in the plurality of optical reading devices.
The exposure apparatus according to a third aspect of the present invention is the exposure apparatus according to the first or second aspect, wherein the inspection processing apparatus compares a reading result of the optical reading apparatus that has read the overlapped area, and reads the same position. It is configured to detect that the optical reader is defective by detecting a discrepancy between the two.

  An exposure apparatus according to a fourth aspect of the present invention is the exposure apparatus according to any one of the first to third aspects, wherein the optical reading device detects a reflected light emitted from the light source and reflected by the exposure mask. It is a reflection type sensor consisting of

  An exposure apparatus according to a fifth aspect of the present invention is the exposure apparatus according to any one of the first to third aspects, wherein the optical reading device detects a transmitted light that is emitted from the light source and transmitted through the exposure mask. It is characterized by being a transmission type sensor consisting of

  An exposure apparatus according to the present invention includes a plurality of optical reading devices that divide an exposure mask arranged at an exposure position into a plurality of areas and inspect each area, and a result read by the plurality of optical reading devices. Since there is provided an inspection processing apparatus that performs a difference process with reference data and determines the presence or absence of defects in the exposure mask, even if the defect inspection target is a large exposure mask used for a flat display, a plurality of The inspection area can be divided and inspected at the same time by the optical reading device of the above, and the inspection time can be shortened, and a special optical sensor having a reading surface of the same size as the exposure mask is created and exposed on this Compared to the case where a mask is arranged and inspection light transmitted through the exposure mask is simultaneously read and inspected, the cost can be reduced.

Hereinafter, embodiments of the present invention will be described with reference to FIGS.
(Embodiment 1)
1 to 3 show an exposure apparatus according to (Embodiment 1) of the present invention.

The exposure apparatus used in the process of forming a pattern such as an electrode on a flat substrate used for a flat display is configured as follows.
In FIG. 1, 1 is a flat substrate on which a photosensitive resin layer is formed, 2 is an exposure mask, and 3 is a stocker in which the exposure mask 2 is stocked.

The exposure process is performed as follows.
The planar substrate 1 is set in close contact with the exposure mask 2 drawn to the exposure position from the stocker 3 as indicated by a virtual line, and the light Ph of the exposure light source 4 is planarized through the exposure mask 2 in this state. The target pattern is baked by irradiating the substrate 1. The planar substrate 1 on which pattern printing has been completed is unloaded from the exposure position, and a target pattern is formed on the planar substrate through a development process and an etching process.

The portion related to defect inspection is configured as follows.
An optical reader 5 that can be moved between a position below the exposure mask 2 set at the exposure position and a retracted position, and a difference process between the result read by the optical reader 5 and predetermined reference data is performed. An inspection processing device 6 for determining the presence or absence of defects in the exposure mask is provided.

  In this embodiment, the optical reading device 5 is composed of first and second optical reading devices 5a and 5b. Each of the first and second optical reading devices 5a and 5b is composed of a reflective sensor including a light source and a sensor that detects reflected light emitted from the light source and reflected by the exposure mask 2.

  Here, as shown in FIG. 2, when the defect inspection area of the exposure mask 2 is divided into a first area 7a and a second area 7b as a plurality of areas in the longitudinal direction (X direction) of the exposure mask 2, The first and second optical reading devices 5a and 5b moved from the retracted position to the lower position of the exposure mask 2 are located at the start position p1 of the first area 7a, and the second optical reading devices 5a and 5b The reading device 5b is located at the start end position p2 of the second area 7b.

The detection widths of the first and second optical reading devices 5a and 5b are set to be equal to or greater than the length of the exposure mask 2 in the width direction.
When the defect inspection is started, the first and second optical reading devices 5a and 5b are directed toward the end of the first and second areas 7a and 7b all at once, through FIG. 2 (b) and FIG. 2 (c). As shown, the first optical reader 5a reads the exposure mask 2 in the first area 7a, and the second optical reader 5b reads the exposure mask 2 in the second area 7b. carry out. Here, the end position of the first area 7a is a position immediately before the start end position p2 of the second area 7b, and p3 represents the end position of the second area 7b.

FIG. 3 shows the configuration of the inspection processing apparatus 6 having a microcomputer as a main part.
First, a non-defective exposure mask 2 is set at an exposure position, and after steps S1, S2 and S3, reference data is read into a non-defective data memory in step S4, and the reading positions of the first and second optical reading devices 5a and 5b. Write in correspondence with. Specifically, occasional read data of the first and second optical reading devices 5a and 5b are read in step S1, and written in the image data buffer in step S2. In step S3, the data is read from the image data buffer written in step S2 and digitally converted by the A / D converter circuit, and this is written in the good data memory in step S4.

More specifically, in step S3, the image data is digitized by converting light and dark of the image data into digital data.
At the time of defect inspection, the read data is written in the acquired image data memory in step S5 through step S1, step S2, and step S3. Subsequently, in step S6, the reference data written in the non-defective data memory in step S4 and the acquired image data memory in step S5 are written in correspondence with the reading positions of the first and second optical reading devices 5a and 5b. A difference is detected by comparing with the inspection data, and it is determined in step S7 whether or not the difference value exceeds a threshold value. If the difference value does not exceed the threshold value, it is determined in step S7 that the exposure mask 2 at that time is a non-defective product. If the difference value exceeds the threshold value, it is determined in step S7 that the exposure mask 2 at that time is defective.

  If it is determined to be a non-defective product, the exposure process of the flat substrate 1 using the exposure mask 2 set at the exposure position is repeatedly performed. The set exposure mask 2 is sent to the cleaning process 8 for cleaning, and a new exposure mask 2 is taken out of the stocker 3 from the stocker 3 and set at the exposure position, and the exposure processing of the flat substrate 1 is performed. The exposure mask 2 that has been cleaned in the cleaning step 8 is returned to the stocker 3, for example.

  As described above, in the defect inspection of the exposure mask 2, the first and second optical reading devices 5a and 5b divide the inspection area into two parts and perform the reading to collect the inspection data. / 2 can be shortened.

Further, since the detection length of the first and second optical reading devices 5a and 5b is shorter than the length of the exposure mask 2, it can be realized at a low cost.
(Embodiment 2)
4 and 5 show (Embodiment 2).

  In (Embodiment 1) shown in FIG. 2, the reading area 7a of the first optical reading device 5a and the reading area 7b of the second optical reading device 5b did not overlap. In 2), the reading area 7c of the first optical reading device 5a is configured to execute reading beyond the start end position p2 of the read area 7b to the end position p4. The inspection processing device 6 is configured as follows.

  In at least one of the reference data collection routine of step S1, step S2, step S3, and step S4 or the inspection data collection routine of step S1, step S2, step S3, and step S5, the reading area 7c and the reading area 7b After the data having the overlapping reading section 7d is accumulated in the memory and step S6 and step S7 are executed, the reliability check is performed as follows in step S8.

  In step S8, the contents of the overlapping reading section 7d of the reading area 7c of the first optical reading device 5a and the starting end positions p2 to p2 of the reading area 7b of the second optical reading device 5b reading the same position as this are read. If the contents at the same reading position of the exposure mask 2 are inconsistent with the contents up to p4, it is determined that there is a problem with the reliability of the first and second optical reading devices 5a and 5b. In S9, it is notified that the first and second optical reading devices 5a and 5b need to be checked. Others are the same as (Embodiment 1).

  By executing steps S8 and S9, it is possible to erroneously determine that the non-defective exposure mask 2 is defective, and to detect useless cleaning and useless replacement of the exposure mask at the exposure position.

  In each embodiment, the optical reading device is a reflective sensor including a light source and a sensor that detects reflected light emitted from the light source and reflected by the exposure mask. A transmissive sensor comprising a sensor that detects the transmitted light emitted from the light source and transmitted through the exposure mask can be similarly implemented.

  Also, the case where the number of optical reading devices is two has been described as an example, but the same applies to the case where the defect inspection area is divided into three or more and a reflective or transmissive sensor is provided for each divided area. Can be implemented.

The block diagram of the principal part of the flat display production line using the exposure apparatus in (Embodiment 1) of this invention Process diagram of movement of defect inspection sensor of exposure apparatus of same embodiment The flowchart which shows the structure of the inspection processing apparatus of the exposure apparatus of the embodiment Process diagram of movement of defect inspection sensor of exposure apparatus in (Embodiment 2) of the present invention The flowchart which shows the structure of the inspection processing apparatus of the exposure apparatus of the embodiment

Explanation of symbols

DESCRIPTION OF SYMBOLS 2 Exposure mask 3 Stocker 5 Optical reader 6 Inspection processing apparatus 5a, 5b 1st, 2nd optical reader 7a 1st area 7b 2nd area p1 Reading start end of 1st area 7a by 1st optical reader 5a Position p2 Reading start end position of the second area 7b by the second optical reading device 5b p3 Reading end position of the second area 7b 7d Overlapping reading section 7c between the reading area 7c and the reading area 7b 7c of the first optical reading device 5a Reading area

Claims (5)

In an exposure apparatus that performs exposure through an exposure mask having a pattern formed on a flat substrate,
A plurality of optical reading devices that divide the exposure mask arranged at an exposure position into a plurality of areas and inspect each area;
An exposure apparatus provided with an inspection processing apparatus that performs a difference process between a result read by the plurality of optical reading apparatuses and predetermined reference data and determines whether or not the exposure mask has a defect. The exposure apparatus according to claim 1, wherein at least a part of the plurality of areas overlaps in the plurality of optical reading devices. 2. The inspection processing apparatus is configured to compare a reading result of the optical reading apparatus that has read the overlapped area and detect a mismatch of reading results at the same location to determine that the optical reading apparatus is faulty. Alternatively, the exposure apparatus according to claim 2. 4. The exposure apparatus according to claim 1, wherein the optical reading device is a reflection type sensor including a light source and a sensor that detects reflected light emitted from the light source and reflected by the exposure mask. The exposure apparatus according to any one of claims 1 to 3, wherein the optical reading device is a transmissive sensor including a light source and a sensor that detects transmitted light that has been emitted from the light source and transmitted through the exposure mask.

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