HK1246405B - Cylindrical mask - Google Patents

Abstract

Provided are a substrate processing apparatus, whereby high-quality substrates can be manufactured with high productivity, a device manufacturing method, and a mask. The present invention is provided with: a mask supporting member that supports a mask pattern such that the pattern is supported along a first surface that is curved in a cylindrical surface shape at a predetermined curvature in a lighting region; a substrate supporting member that supports the substrate such that the substrate is supported along a predetermined second surface in a projection region; and a drive mechanism, which rotates the mask supporting member such that the mask pattern moves in the predetermined scanning exposure direction, and which also moves the substrate supporting member such that the substrate moves in the scanning exposure direction. The mask supporting member satisfies formula of 1.3≤L/φ≤3.8, where a diameter of the first surface is represented by φ, and a first surface length in the direction orthogonal to the scanning exposure direction is represented by L.

Description

Cylindrical light mask

This invention application is a divisional application of an invention application with an international application date of March 26, 2014, an international application number of PCT/JP2014/058590, a national application number of 201480037519.5 entering the Chinese national phase, and an invention name of “Substrate processing device, device manufacturing method and cylindrical mask”.

Technical Field

The present invention relates to a substrate processing device, a device manufacturing method and a cylindrical photomask for projecting a pattern of a photomask onto a substrate and exposing the pattern on the substrate.

Background Art

There is a device manufacturing system for manufacturing various devices such as display devices such as liquid crystal displays and semiconductors. The device manufacturing system is equipped with a substrate processing device such as an exposure device. The substrate processing device described in Patent Document 1 projects an image of a pattern formed on a mask arranged in an illumination area onto a substrate arranged in a projection area, and exposes the pattern on the substrate. The masks used in the substrate processing device include a planar mask, a cylindrical mask, and the like.

Prior art literature

Patent Literature

Patent Document 1: Japanese Patent Application Publication No. 2007-299918

The substrate processing device can continuously expose the substrate by making the photomask cylindrical and rotating the photomask. In addition, as a substrate processing device, there is also a roll-to-roll method in which the substrate is made into a long thin sheet and continuously fed under the projection area. In this way, the substrate processing device can rotate the cylindrical photomask, and as a substrate conveying method, by using the roll-to-roll method, both the substrate and the photomask can be continuously conveyed.

Here, substrate processing apparatuses are generally required to efficiently expose a pattern on a substrate to improve productivity. This is also true when a cylindrical mask is used as a mask.

Summary of the invention

An object of the present invention is to provide a substrate processing apparatus, a device manufacturing method, and a cylindrical photomask capable of producing high-quality substrates with high productivity.

According to a first embodiment of the present invention, there is provided a substrate processing device comprising: a projection optical system which projects a light beam from a pattern of a mask arranged in an illumination area of an illumination light onto a projection area where a substrate is arranged; a mask supporting member which supports the pattern of the mask in the illumination area along a first surface bent into a cylindrical shape with a specified curvature; a substrate supporting member which supports the substrate in the projection area along a specified second surface; and a driving mechanism which rotates the mask supporting member in a manner that moves the pattern of the mask in a specified scanning exposure direction, and moves the substrate supporting member in a manner that moves the substrate in the scanning exposure direction, wherein the mask supporting member satisfies 1.3≤L/φ≤3.8 when the diameter of the first surface is set to φ and the length of the first surface in a direction orthogonal to the scanning exposure direction is set to L.

According to a second aspect of the present invention, there is provided a device manufacturing method, comprising: forming the pattern of the mask on the substrate using the substrate processing apparatus according to the first aspect; and supplying the substrate to the substrate processing apparatus.

According to a third embodiment of the present invention, a cylindrical mask is provided, which has a mask pattern for electronic devices formed along a cylindrical outer surface and is capable of rotating around a center line. The cylindrical mask has a cylindrical substrate with a diameter of φ on the outer surface and a length of La on the outer surface in the direction of the center line. When the maximum length of the mask pattern that can be formed on the outer surface of the cylindrical substrate in the direction of the center line is set to L, within the range of L≤La, the ratio L/φ of the diameter φ to the length L is set to a range of 1.3≤L/φ≤3.8.

According to a fourth aspect of the present invention, there is provided a cylindrical mask having a mask pattern formed along a cylindrical surface having a fixed radius relative to a predetermined center line, and being mounted on an exposure device in a manner rotatable around the center line, wherein on the cylindrical surface, n (n≥2) rectangular mask areas for display panels are arranged in a manner spaced apart by intervals Sx in a circumferential direction of the cylindrical surface, the mask area including a display screen area having a long side dimension Ld, a short side dimension Lc, and an aspect ratio Asp of Ld/Lc, and a peripheral circuit area arranged adjacent to the periphery thereof, when the dimension L of the mask area in the long side direction is set to _e1 times ( _e1≥1 ) the long side dimension Ld of the display screen area, and the dimension of the mask area in the short side direction is set to _e2 times (e2≥1 ₎ the short side dimension Lc of the display screen area. ≥1), the length of the cylindrical surface in the direction of the center line is set to be greater than the dimension L, and when the diameter of the cylindrical surface is set to φ and the pi is set to πφ＝n(e ₂ ·Lc+Sx), and further, the diameter φ, the number n, and the interval Sx are set in such a way that the ratio L/φ of the dimension L to the diameter φ is in the range of 1.3≤L/φ≤3.8.

Effects of the Invention

According to the method of the present invention, by setting the relationship between the diameter φ of the cylindrical mask shape held by the mask support member or the cylindrical shape of the pattern formed on the mask and the length L to the above range, the device pattern can be efficiently exposed and transferred with high productivity. In addition, by setting the relationship between the diameter φ and the length L to the above range, even when multiple patterns for display panels are arranged on multiple surfaces along the circumferential surface of the cylindrical mask, panels of various display sizes can be efficiently arranged.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram showing the overall configuration of a device manufacturing system according to a first embodiment.

FIG. 2 is a diagram showing the overall configuration of an exposure apparatus (substrate processing apparatus) according to the first embodiment.

FIG. 3 is a diagram showing the arrangement of an illumination area and a projection area of the exposure device shown in FIG. 2 .

FIG. 4 is a diagram showing the configuration of an illumination optical system and a projection optical system of the exposure apparatus shown in FIG. 2 .

FIG. 5 is a diagram showing the state of the illumination light beam irradiated on the cylindrical mask and the state of the projection light beam generated from the cylindrical mask.

FIG. 6 is a perspective view showing a schematic structure of a cylindrical wheel and a photomask constituting the cylindrical photomask.

FIG. 7 is a development diagram showing an example of arrangement in which a mask for a display panel is arranged on the mask surface of a cylindrical mask.

FIG. 8 is a development view showing an example of arrangement in which three masks of the same size are arranged in a row on three surfaces on the mask surface of a cylindrical mask.

FIG. 9 is a development view showing an example of arrangement in which four masks of the same size are arranged in a row on four surfaces of the mask surface of a cylindrical mask.

FIG. 10 is a development diagram showing an example of arrangement in which masks of the same size are arranged in two rows and two columns on four surfaces of a mask surface of a cylindrical mask.

FIG. 11 is a development diagram for explaining an example of arrangement of both sides of a photomask for a display panel having an aspect ratio of 2:1.

FIG. 12 is a graph showing the relationship between the diameter of a simulated cylindrical mask and the exposure slit width under a specific defocus tolerance.

FIG. 13 is a development view showing a specific example in which photomasks for a 60-inch display panel are arranged on one surface.

FIG. 14 is a development view showing an example of arrangement of both sides of a mask.

FIG. 15 is a development view showing a first arrangement example of both sides of a mask for a 32-inch display panel.

FIG. 16 is a development view showing a second arrangement example of both sides of a mask for a 32-inch display panel.

FIG. 17 is a development view showing a specific example in which photomasks for a 32-inch display panel are arranged on one surface.

FIG. 18 is a development view showing a specific example of the arrangement of three surfaces of a photomask for a 32-inch display panel.

FIG. 19 is a development view showing a specific example of the arrangement of three surfaces of a mask for a 37-inch display panel.

FIG. 20 is a diagram showing the overall configuration of an exposure apparatus (substrate processing apparatus) according to a second embodiment.

FIG. 21 is a diagram showing the overall configuration of an exposure apparatus (substrate processing apparatus) according to a third embodiment.

FIG. 22 is a flowchart showing a device manufacturing method performed by the device manufacturing system.

DETAILED DESCRIPTION

The mode (implementation mode) for implementing the present invention is described in detail as follows with reference to the accompanying drawings. The present invention is not limited to the contents described in the following implementation modes. In addition, the constituent elements described below certainly include elements that are easily thought of by a person skilled in the art, and substantially the same elements. Furthermore, the constituent elements described below can be appropriately combined. In addition, various omissions, substitutions or changes of constituent elements can be made without departing from the gist of the present invention. For example, in the following implementation modes, although the case of manufacturing a flexible display is described as an example as a device, it is not limited to this. As a device, a wiring substrate having a wiring pattern formed of copper foil, etc., a substrate having a plurality of semiconductor devices (transistors, diodes, etc.) formed thereon, etc. can also be manufactured.

[First embodiment]

In the first embodiment, a substrate processing device that performs exposure processing on a substrate is an exposure device. In addition, the exposure device is incorporated into a device manufacturing system that performs various processing on the exposed substrate to manufacture a device. First, the device manufacturing system is described.

<Device Manufacturing System>

FIG. 1 is a diagram showing the structure of a device manufacturing system of the first embodiment. The device manufacturing system 1 shown in FIG. 1 is a production line (flexible display production line) for manufacturing a flexible display as a device. As a flexible display, there is an organic EL display, etc. The device manufacturing system 1 delivers the substrate P from a supply reel FR1 that winds the flexible substrate P into a roll shape, and after continuously applying various treatments to the delivered substrate P, the processed substrate P is wound onto a recovery reel FR2 as a flexible device, which is the so-called roll-to-roll method. In the device manufacturing system 1 of the first embodiment, an example is shown in which a thin film sheet, i.e., a substrate P, is delivered from a supply reel FR1, and the substrate P delivered from the supply reel FR1 passes through n processing devices U1, U2, U3, U4, U5, ... Un in sequence until it is wound onto a recovery reel FR2. First, the substrate P that is the processing object of the device manufacturing system 1 is described.

The substrate P is made of, for example, a resin film, a foil made of a metal such as stainless steel, or an alloy. The material of the resin film may be, for example, one or more of polyethylene resin, polypropylene resin, polyester resin, vinyl copolymer resin, polyvinyl chloride resin, cellulose resin, polyamide resin, polyimide resin, polycarbonate resin, polystyrene resin, and vinyl acetate resin.

The substrate P is preferably selected from a material with a significantly low thermal expansion coefficient, so that the deformation caused by heat in various treatments applied to the substrate P can be substantially ignored. The thermal expansion coefficient can also be set to be smaller than a threshold value of the corresponding process temperature, etc., by mixing an inorganic filler into the resin film. The inorganic filler can be, for example, titanium oxide, zinc oxide, aluminum oxide, silicon oxide, etc. In addition, the substrate P can be a single layer of extremely thin glass with a thickness of about 100 μm manufactured by a float method, etc., or it can be a laminated body with the above-mentioned resin film, foil, etc. bonded to the extremely thin glass.

The substrate P thus constructed becomes a supply reel FR1 by being wound into a reel shape, and the supply reel FR1 is installed on the device manufacturing system 1. The device manufacturing system 1 equipped with the supply reel FR1 repeatedly performs various processes for manufacturing a device on the substrate P sent out from the supply reel FR1. As a result, the processed substrate P becomes a state in which a plurality of devices are connected. In other words, the substrate P sent out from the supply reel FR1 becomes a substrate for configuring multiple surfaces. In addition, the substrate P can also be a substrate whose surface is modified and activated by a predetermined pretreatment, or a substrate on which a fine partition wall structure (concave-convex structure) for precise patterning is formed on the surface by an imprinting method.

The processed substrate P is recycled as a recycling reel FR2 by being wound into a roll shape. The recycling reel FR2 is installed on a cutting device not shown in the figure. The cutting device equipped with the recycling reel FR2 divides (cuts) the processed substrate P into multiple devices for each device. Regarding the size of the substrate P, for example, the size in the width direction (the direction of the short side) is about 10 cm to 2 m, and the size in the length direction (the direction of the long side) is more than 10 m. In addition, the size of the substrate P is not limited to the above-mentioned size.

FIG1 forms an orthogonal coordinate system in which the X direction, the Y direction, and the Z direction are orthogonal to each other. The X direction is the direction connecting the supply reel FR1 and the recovery reel FR2 in the horizontal plane, and is the left-right direction in FIG1. The Y direction is the direction orthogonal to the X direction in the horizontal plane, and is the front-back direction in FIG1. The Y direction becomes the axial direction of the supply reel FR1 and the recovery reel FR2. The Z direction is the vertical direction, and is the up-down direction in FIG1.

The device manufacturing system 1 includes: a substrate supply device 2 for supplying a substrate P; a processing device U1~Un for performing various processes on the substrate P supplied by the substrate supply device 2; a substrate recovery device 4 for recovering the substrate P processed by the processing devices U1~Un; and a higher-level control device 5 for controlling each device of the device manufacturing system 1.

A supply reel FR1 is rotatably mounted on the substrate supply device 2. The substrate supply device 2 includes a driving roller DR1 that delivers the substrate P from the mounted supply reel FR1, and an edge position controller EPC1 that adjusts the position of the substrate P in the width direction (Y direction). The driving roller DR1 rotates while clamping the front and back surfaces of the substrate P, and delivers the substrate P from the supply reel FR1 in the conveying direction toward the recovery reel FR2, thereby supplying the substrate P to the processing devices U1 to Un. At this time, the edge position controller EPC1 moves the substrate P in the width direction in such a way that the position of the end portion (edge) of the substrate P in the width direction falls within a range of about ± a dozen μm to about ± several dozen μm relative to the target position, thereby correcting the position of the substrate P in the width direction.

A recovery reel FR2 is rotatably mounted on the substrate recovery device 4. The substrate recovery device 4 has a driving roller DR2 that pulls the processed substrate P toward the recovery reel FR2, and an edge position controller EPC2 that adjusts the position of the substrate P in the width direction (Y direction). The substrate recovery device 4 rotates while clamping the front and back surfaces of the substrate P with the driving roller DR2, pulls the substrate P in the conveying direction, and rotates the recovery reel FR2, thereby rolling up the substrate P. At this time, the edge position controller EPC2 has the same structure as the edge position controller EPC1, and corrects the position of the substrate P in the width direction to avoid the width end (edge) of the substrate P being irregular in the width direction.

The processing device U1 is a coating device that coats a photosensitive functional liquid on the surface of a substrate P supplied from a substrate supply device 2. As the photosensitive functional liquid, for example, a photoresist, a photosensitive silane coupling agent material (photosensitive hydrophilicity modification material, photosensitive electroplating reduction material, etc.), a UV curing resin liquid, etc. are used. The processing device U1 is provided with a coating mechanism Gp1 and a drying mechanism Gp2 in sequence from the upstream side in the conveying direction of the substrate P. The coating mechanism Gp1 has a pressure roller R1 that winds the substrate P, and a coating roller R2 that is opposite to the pressure roller R1. The coating mechanism Gp1 clamps the substrate P by the pressure roller R1 and the coating roller R2 while the supplied substrate P is wound on the pressure roller R1. Then, the coating mechanism Gp1 rotates the pressure roller R1 and the coating roller R2, and coats the substrate P with the photosensitive functional liquid by the coating roller R2 while moving the substrate P in the conveying direction. The drying mechanism Gp2 blows out drying air such as hot air or dry air to remove the solute (solvent or water) contained in the photosensitive functional liquid, and dries the substrate P coated with the photosensitive functional liquid, thereby forming a photosensitive functional layer on the substrate P.

The processing device U2 is a heating device that heats the substrate P conveyed from the processing device U1 to a predetermined temperature (e.g., about 10 to 120°C) in order to stabilize the photosensitive functional layer formed on the surface of the substrate P. The processing device U2 is provided with a heating chamber HA1 and a cooling chamber HA2 in order from the upstream side of the conveying direction of the substrate P. The heating chamber HA1 is provided with a plurality of rollers and a plurality of air turn bars inside thereof, and the plurality of rollers and the plurality of air turn bars constitute the conveying path of the substrate P. The plurality of rollers are arranged in a manner of rolling contact with the back of the substrate P, and the plurality of air turn bars are arranged on the surface side of the substrate P in a non-contact state. The plurality of rollers and the plurality of air turn bars are arranged in a zigzag conveying path in order to lengthen the conveying path of the substrate P. The substrate P passing through the heating chamber HA1 is heated to a predetermined temperature while being conveyed along the zigzag conveying path. The cooling chamber HA2 cools the substrate P to the ambient temperature in order to make the temperature of the substrate P heated in the heating chamber HA1 consistent with the ambient temperature of the subsequent process (processing device U3). The cooling chamber HA2 is provided with a plurality of rollers therein, and the plurality of rollers are arranged in a zigzag conveying path in order to lengthen the conveying path of the substrate P, similarly to the heating chamber HA1. The substrate P passing through the cooling chamber HA2 is conveyed along the zigzag conveying path while being cooled. A driving roller DR3 is provided on the downstream side of the conveying direction of the cooling chamber HA2, and the driving roller DR3 rotates while clamping the substrate P after passing through the cooling chamber HA2, thereby supplying the substrate P toward the processing device U3.

The processing device (substrate processing device) U3 is an exposure device that projects and exposes a pattern of a display circuit or wiring, etc., on a substrate (photosensitive substrate) P having a photosensitive functional layer formed on the surface thereof, which is supplied from the processing device U2. As will be described in detail later, the processing device U3 illuminates a reflective cylindrical mask M (cylindrical wheel 21) with an illumination beam, and projects and exposes a projection beam obtained by reflecting the illumination beam from the mask M onto the substrate P. The processing device U3 has a driving roller DR4 that sends the substrate P supplied from the processing device U2 to the downstream side in the conveying direction, and an edge position controller EPC3 that adjusts the position of the substrate P in the width direction (Y direction). The driving roller DR4 rotates while clamping the front and back surfaces of the substrate P, and sends the substrate P to the downstream side in the conveying direction, thereby supplying the substrate P to a rotating cylinder (substrate support cylinder) 25 that stably supports it at the exposure position. The edge position controller EPC3 has the same structure as the edge position controller EPC1, and corrects the position of the substrate P in the width direction so that the width direction of the substrate P at the exposure position becomes the target position.

In addition, the processing device U3 is provided with a buffer section DL, which has two sets of drive rollers DR6 and DR7 for conveying the substrate P to the downstream side in the conveying direction in a state where the exposed substrate P is given slack. The two sets of drive rollers DR6 and DR7 are arranged at a predetermined interval in the conveying direction of the substrate P. The drive roller DR6 rotates while clamping the upstream side of the conveyed substrate P, and the drive roller DR7 rotates while clamping the downstream side of the conveyed substrate P, thereby supplying the substrate P to the processing device U4. At this time, since the substrate P is given slack, it can absorb the change in conveying speed generated on the downstream side of the conveying direction compared with the drive roller DR7, and can eliminate the influence of the change in conveying speed on the exposure processing of the substrate P. In addition, in the processing device U3, in order to align the image of a portion of the mask pattern of the cylindrical mask M (hereinafter simply referred to as the mask M) relative to the substrate P, collimating microscopes AMG1 and AMG2 are provided to detect alignment marks pre-formed on the substrate P, or reference patterns formed on a portion of the outer peripheral surface of the rotating cylinder (substrate supporting cylinder) 25.

The processing device U4 is a wet processing device that performs wet development processing, non-electrolytic plating processing, etc. on the exposed substrate P transported from the processing device U3. The processing device U4 has three processing tanks BT1, BT2, BT3 layered in the vertical direction (Z direction) and a plurality of rollers for transporting the substrate P. The plurality of rollers are arranged in such a manner that the interiors of the three processing tanks BT1, BT2, BT3 are formed into a transport path for the substrate P to pass through in sequence. A driving roller DR8 is provided on the downstream side of the transport direction of the processing tank BT3, and the driving roller DR8 rotates while clamping the substrate P after passing through the processing tank BT3, thereby supplying the substrate P to the processing device U5.

Although not shown in the figure, the processing device U5 is a drying device that dries the substrate P transported from the processing device U4. The processing device U5 removes droplets attached to the substrate P after the wet treatment in the processing device U4, and adjusts the moisture content of the substrate P. The substrate P dried by the processing device U5 is further transported to the processing device Un after passing through several processing devices. Then, after being processed by the processing device Un, the substrate P is wound onto the recovery reel FR2 of the substrate recovery device 4.

The upper control device 5 coordinates and controls the substrate supply device 2, the substrate recovery device 4, and the plurality of processing devices U1 to Un. The upper control device 5 controls the substrate supply device 2 and the substrate recovery device 4 to transport the substrate P from the substrate supply device 2 to the substrate recovery device 4. In addition, the upper control device 5 controls the plurality of processing devices U1 to Un in synchronization with the transport of the substrate P, so that the plurality of processing devices U1 to Un perform various processes on the substrate P.

<Exposure apparatus (substrate processing apparatus)>

Next, the structure of the exposure device (substrate processing device) as the processing device U3 of the first embodiment is described with reference to FIGS. 2 to 5. FIG. 2 is a diagram showing the overall structure of the exposure device (substrate processing device) of the first embodiment. FIG. 3 is a diagram showing the configuration of the illumination area and the projection area of the exposure device shown in FIG. 2. FIG. 4 is a diagram showing the structure of the illumination optical system and the projection optical system of the exposure device shown in FIG. 2. FIG. 5 is a diagram showing the state of the illumination beam irradiated on the photomask and the projection beam emitted from the photomask.

The exposure device U3 shown in FIG2 is a so-called scanning exposure device, which projects and exposes the image of the mask pattern formed on the outer peripheral surface of the cylindrical mask M onto the surface of the substrate P while conveying the substrate P along the conveying direction. In addition, an orthogonal coordinate system in which the X direction, the Y direction, and the Z direction are orthogonal is formed in FIG2, which is the same orthogonal coordinate system as FIG1.

First, the mask M (cylindrical mask M in FIG. 1 ) used for the exposure device U3 is described. The mask M is, for example, a reflective mask using a metal cylindrical body. The pattern of the mask M is formed on a cylindrical substrate having an outer peripheral surface (circumferential surface) with a radius of curvature Rm centered on a first axis AX1 extending in the Y direction. The circumferential surface of the mask M becomes a mask surface (first surface) P1 formed with a prescribed mask pattern. The mask surface P1 includes a high-reflection portion that reflects a light beam in a prescribed direction with high efficiency, and a reflection suppression portion (low-reflection portion) that does not reflect or reflects a light beam in a prescribed direction with low efficiency. The mask pattern is formed by a high-reflection portion and a reflection suppression portion. Here, the reflection suppression portion only needs to reduce the light reflected in the prescribed direction. Therefore, the reflection suppression portion can be composed of a material that absorbs light, a material that allows light to pass through, or a material that diffracts light except in a specific direction. As the mask M of the above-mentioned structure, the exposure device U3 can use a mask made of a cylindrical substrate of a metal such as aluminum or SUS. Therefore, the exposure device U3 can perform exposure using an inexpensive mask.

In addition, the mask M may be formed with the whole or a part of a panel pattern corresponding to one display device, or may be formed with panel patterns corresponding to multiple display devices. In addition, the mask M may be a multi-faceted mask with multiple panel patterns repeatedly formed in the circumferential direction around the first axis AX1, or a multi-faceted mask with multiple small panel patterns repeatedly formed in the direction parallel to the first axis AX1. Furthermore, the mask M may be a multi-faceted mask with different-sized patterns formed by forming a panel pattern for a first display device and a panel pattern for a second display device that is different in size from the first display device. In addition, the mask M only needs to have a circumferential surface with a curvature radius of Rm centered on the first axis AX1, and is not limited to the shape of a cylinder. For example, the mask M may also be an arc-shaped plate having a circumferential surface. In addition, the mask M may be a thin plate, or the thin plate-shaped mask M may be bent to have a circumferential surface.

Next, the exposure device U3 shown in FIG2 is described. The exposure device U3 has the above-mentioned drive rollers DR4, DR6, DR7, substrate support cylinder 25, edge position controller EPC3 and collimating microscopes AMG1, AMG2, and also has a mask holding mechanism 11, a substrate support mechanism 12, an illumination optical system IL, a projection optical system PL, and a lower control device 16. The exposure device U3 irradiates the illumination light emitted from the light source device 13 via a part of the illumination optical system IL and the projection optical system PL onto the mask surface P1 on which a pattern is formed of the mask M supported by the mask holding cylinder 21 (hereinafter also referred to as the cylindrical wheel 21) of the mask holding mechanism 11, and projects the projection light beam (imaging light) reflected on the mask surface P1 of the mask M via the projection optical system PL onto the substrate P supported by the substrate support cylinder 25 of the substrate support mechanism 12.

The lower control device 16 controls each part of the exposure device U3 and causes each part to perform processing. The lower control device 16 may be a part or all of the upper control device 5 of the device manufacturing system 1. In addition, the lower control device 16 may also be another device that is controlled by the upper control device 5 and is different from the upper control device 5. The lower control device 16 includes, for example, a computer.

The mask holding mechanism 11 includes a cylindrical wheel 21 that holds the mask M and a first drive unit 22 that rotates the cylindrical wheel 21. The cylindrical wheel 21 holds the mask M as a cylinder with a curvature radius Rm with the first axis AX1 as the rotation center. The first drive unit 22 is connected to the lower control device 16 and rotates the cylindrical wheel 21 with the first axis AX1 as the rotation center.

In addition, although the cylindrical wheel 21 of the mask holding mechanism 11 directly forms a mask pattern on its outer circumference by a high-reflection portion and a low-reflection portion, it is not limited to this structure. The cylindrical wheel 21 as the mask holding mechanism 11 can also wind and hold a thin plate-shaped reflective mask M along its outer circumference. In addition, the cylindrical wheel 21 as the mask holding mechanism 11 can also hold a plate-shaped reflective mask M pre-bent into an arc shape with a radius Rm on the outer circumference of the cylindrical wheel 21 so that it can be installed and removed.

The substrate support mechanism 12 has: a substrate support cylinder 25 that supports the substrate P; a second drive unit 26 that rotates the substrate support cylinder 25; a pair of air flip rods ATB1, ATB2; and a pair of guide rollers 27, 28. The substrate support cylinder 25 is formed into a cylindrical shape having an outer peripheral surface (circumferential surface) with a curvature radius Rp centered on the second axis AX2 extending in the Y direction. Here, the first axis AX1 and the second axis AX2 are parallel to each other, and the surface passing through (including) the first axis AX1 and the second axis AX2 is set as the center plane CL. A part of the circumferential surface of the substrate support cylinder 25 becomes the supporting surface P2 that supports the substrate P. In other words, the substrate support cylinder 25 stably supports the substrate P by winding the substrate P onto its supporting surface P2 so that the substrate P is bent into a cylindrical surface shape. The second drive unit 26 is connected to the lower control device 16, and rotates the substrate support cylinder 25 with the second axis AX2 as the rotation center. A pair of air turning bars ATB1, ATB2 and a pair of guide rollers 27, 28 are respectively arranged on the upstream side and the downstream side of the conveying direction of the substrate P, separated from the substrate support cylinder 25. The guide roller 27 guides the substrate P conveyed from the driving roller DR4 to the substrate support cylinder 25 via the air turning bar ATB1, and the guide roller 28 guides the substrate P conveyed from the air turning bar ATB2 via the substrate support cylinder 25 to the driving roller DR6.

The substrate supporting mechanism 12 rotates the substrate supporting cylinder 25 by the second driving unit 26 , thereby conveying the substrate P introduced into the substrate supporting cylinder 25 in the longitudinal direction (X direction) at a predetermined speed while being supported by the supporting surface P2 of the substrate supporting cylinder 25 .

At this time, the lower control device 16 connected to the first drive unit 22 and the second drive unit 26 continuously and repeatedly scans and exposes the projection image of the mask pattern formed on the mask surface P1 of the mask M to the surface (surface curved along the circumferential surface) of the substrate P wound on the support surface P2 of the substrate support cylinder 25 by making the cylindrical wheel 21 rotate synchronously with the substrate support cylinder 25 at a specified rotation speed ratio. The exposure device U3, the first drive unit 22 and the second drive unit 26 constitute the moving mechanism of this embodiment. In addition, in the exposure device U3 shown in FIG. 2, the portion located on the upstream side of the conveying direction of the substrate P compared to the guide roller 27 becomes a substrate supply unit that supplies the substrate P to the support surface P2 of the substrate support cylinder 25. The supply reel FR1 shown in FIG. 1 can also be directly set on the substrate supply unit. Similarly, the portion located on the downstream side of the conveying direction of the substrate P compared to the guide roller 28 becomes a substrate recovery unit that recovers the substrate P from the support surface P2 of the substrate support cylinder 25. The recovery reel FR2 shown in FIG. 1 can also be directly set on the substrate recovery unit.

The light source device 13 emits an illumination beam EL1 for illuminating the mask M. The light source device 13 includes a light source 31 and a light guide member 32. The light source 31 is a light source that emits light of a specified wavelength. The light source 31 is, for example, a lamp light source such as a mercury lamp, a gas laser light source such as an excimer laser, a laser diode, a solid laser light source such as a light emitting diode (LED), etc. The illumination light emitted by the light source 31 can utilize bright lines (g lines, h lines, i lines) in the ultraviolet region when a mercury lamp is used, and can utilize far ultraviolet light (DUV light) such as a KrF excimer laser (wavelength 248nm) or an ArF excimer laser (wavelength 193nm) when an excimer laser light source is used. Here, the light source 31 preferably emits an illumination beam EL1 including a wavelength shorter than the i line (wavelength of 365nm). As such an illumination beam EL1, a laser (wavelength 355nm) emitted as the third harmonic of a YAG laser and a laser (wavelength 266nm) emitted as the fourth harmonic of a YAG laser can also be used.

The light guide component 32 guides the illumination light beam EL1 emitted from the light source 31 to the illumination optical system IL. The light guide component 32 is composed of an optical fiber, a relay module using a reflector, or the like. In addition, when a plurality of illumination optical systems IL are provided, the light guide component 32 divides the illumination light beam EL1 from the light source 31 into a plurality of light beams, and guides the plurality of illumination light beams EL1 to the plurality of illumination optical systems IL. The light guide component 32 of the present embodiment allows the illumination light beam EL1 emitted from the light source 31 to be incident on the polarization beam splitter PBS as light of a predetermined polarization state. The polarization beam splitter PBS is provided between the light mask M and the projection optical system PL in order to perform vertical illumination on the light mask M, reflects a light beam of linear polarized light that becomes S polarized light, and transmits a light beam of linear polarized light that becomes P polarized light. Therefore, the light source device 13 emits the illumination light beam EL1 that makes the illumination light beam EL1 incident on the polarization beam splitter PBS a light beam of linear polarized light (S polarized light). The light source device 13 emits polarized laser light having a consistent wavelength and phase to the polarization beam splitter PBS. For example, when the light beam emitted from the light source 31 is polarized light, the light source device 13 uses a polarization-maintaining optical fiber as the light guide component 32 to guide the light while maintaining the polarization state of the laser output from the light source device 13. In addition, for example, the light beam output from the light source 31 can also be guided by an optical fiber, and the light output from the optical fiber can be polarized by a polarizer. That is, when a randomly polarized light beam is guided by the light source device 13, the randomly polarized light beam can also be polarized by a polarizer. In addition, the light source device 13 can also guide the light beam output from the light source 31 by using a relay optical system such as a lens.

Here, as shown in FIG3 , the exposure device U3 of the first embodiment is an exposure device that assumes a so-called multi-lens method. In addition, FIG3 shows a top view of the illumination area IR on the mask M held on the cylindrical wheel 21 observed from the -Z side (the left figure of FIG3 ), and a top view of the projection area PA on the substrate P supported by the substrate support cylinder 25 observed from the +Z side (the right figure of FIG3 ). The reference symbol Xs in FIG3 represents the moving direction (rotation direction) of the cylindrical wheel 21 and the substrate support cylinder 25. The exposure device U3 of the multi-lens method illuminates the multiple (for example, six in the first embodiment) illumination areas IR1 to IR6 on the mask M with the illumination light beam EL1, and projects and exposes the multiple projection light beams EL2 obtained by reflecting each illumination light beam EL1 from each illumination area IR1 to IR6 to the multiple (for example, six in the first embodiment) projection areas PA1 to PA6 on the substrate P.

First, the multiple illumination areas IR1 to IR6 illuminated by the illumination optical system IL are described. As shown in FIG. 3 , the multiple illumination areas IR1 to IR6 are separated by the center plane CL, and the first illumination area IR1, the third illumination area IR3, and the fifth illumination area IR5 are arranged on the mask M on the upstream side in the rotation direction, and the second illumination area IR2, the fourth illumination area IR4, and the sixth illumination area IR6 are arranged on the mask M on the downstream side in the rotation direction. Each illumination area IR1 to IR6 becomes an elongated trapezoidal area having parallel short sides and long sides extending along the axial direction (Y direction) of the mask M. At this time, each illumination area IR1 to IR6 of the trapezoid becomes an area whose short side is located on the center plane CL side and whose long side is located on the outside. The first illumination area IR1, the third illumination area IR3, and the fifth illumination area IR5 are arranged at a predetermined interval in the axial direction. In addition, the second illumination area IR2, the fourth illumination area IR4, and the sixth illumination area IR6 are arranged at a predetermined interval in the axial direction. At this time, the second illumination area IR2 is arranged between the first illumination area IR1 and the third illumination area IR3 in the axial direction. Similarly, the third illumination area IR3 is arranged between the second illumination area IR2 and the fourth illumination area IR4 in the axial direction. The fourth illumination area IR4 is arranged between the third illumination area IR3 and the fifth illumination area IR5 in the axial direction. The fifth illumination area IR5 is arranged between the fourth illumination area IR4 and the sixth illumination area IR6 in the axial direction. Each illumination area IR1 to IR6 is arranged in such a manner that the triangular portions of the hypotenuse portions of the trapezoidal illumination areas adjacent to each other along the Y direction overlap each other when they rotate along the circumferential direction (X direction) of the light shield M. In addition, in the first embodiment, although each illumination area IR1 to IR6 is a trapezoidal area, it may also be a rectangular area.

In addition, the mask M has a pattern forming area A3 in which a mask pattern is formed, and a non-pattern forming area A4 in which no mask pattern is formed. The non-pattern forming area A4 is a low-reflection area (reflection suppression part) that is difficult to reflect the illumination light beam EL1, and is configured in a frame-like manner to surround the pattern forming area A3. The first to sixth illumination areas IR1 to IR6 are configured to cover the full width of the pattern forming area A3 in the Y direction.

The illumination optical system IL is provided in plurality (for example, six in the first embodiment) corresponding to the plurality of illumination regions IR1 to IR6. The illumination light beam EL1 from the light source device 13 is incident on the plurality of illumination optical systems (divided illumination optical systems) IL1 to IL6, respectively. Each illumination optical system IL1 to IL6 guides each illumination light beam EL1 incident from the light source device 13 to each illumination region IR1 to IR6, respectively. That is, the first illumination optical system IL1 guides the illumination light beam EL1 to the first illumination region IR1, and similarly, the second to sixth illumination optical systems IL2 to IL6 guide the illumination light beam EL1 to the second to sixth illumination regions IR2 to IR6. The plurality of illumination optical systems IL1 to IL6 are separated from each other by the center plane CL, and the first illumination optical system IL1, the third illumination optical system IL3, and the fifth illumination optical system IL5 are arranged on the side (left side in FIG. 2) where the first, third, and fifth illumination regions IR1, IR3, and IR5 are arranged. The first illumination optical system IL1, the third illumination optical system IL3, and the fifth illumination optical system IL5 are arranged at predetermined intervals in the Y direction. In addition, the plurality of illumination optical systems IL1 to IL6 are separated by the center plane CL, and the second illumination optical system IL2, the fourth illumination optical system IL4, and the sixth illumination optical system IL6 are arranged on the side (the right side of FIG. 2) where the second, fourth, and sixth illumination regions IR2, IR4, and IR6 are arranged. The second illumination optical system IL2, the fourth illumination optical system IL4, and the sixth illumination optical system IL6 are arranged at predetermined intervals in the Y direction. At this time, the second illumination optical system IL2 is arranged between the first illumination optical system IL1 and the third illumination optical system IL3 in the axial direction. Similarly, the third illumination optical system IL3, the fourth illumination optical system IL4, and the fifth illumination optical system IL5 are arranged between the second illumination optical system IL2 and the fourth illumination optical system IL4, between the third illumination optical system IL3 and the fifth illumination optical system IL5, and between the fourth illumination optical system IL4 and the sixth illumination optical system IL6 in the axial direction, respectively. Moreover, the 1st illumination optical system IL1, the 3rd illumination optical system IL3, and the 5th illumination optical system IL5 and the 2nd illumination optical system IL2, the 4th illumination optical system IL4, and the 6th illumination optical system IL6 are arrange|positioned symmetrically when viewed from the Y direction.

Next, each illumination optical system IL1 to IL6 will be described with reference to Fig. 4. In addition, since each illumination optical system IL1 to IL6 has the same configuration, the first illumination optical system IL1 (hereinafter simply referred to as illumination optical system IL) will be described as an example.

The illumination optical system IL performs Kohler illumination on the illumination region IR on the mask M with the illumination light beam EL1 from the light source 31 of the light source device 13 in order to illuminate the illumination region IR (first illumination region IR1) with uniform illumination. In addition, the illumination optical system IL is a broadside illumination system using a polarization beam splitter PBS. The illumination optical system IL includes an illumination optical module ILM, a polarization beam splitter PBS, and a quarter wavelength plate 41 in order from the incident side of the illumination light beam EL1 from the light source device 13.

As shown in FIG4 , the illumination optical module ILM includes a collimator lens 51, a fly-eye lens 52, a plurality of condenser lenses 53, a cylindrical lens 54, an illumination field aperture 55, and a relay lens system 56 in order from the incident side of the illumination light beam EL1, and is arranged on the first optical axis BX1. The collimator lens 51 receives light emitted from the light guide component 32 and illuminates the entire surface of the incident side of the fly-eye lens 52. The center of the surface on the emission side of the fly-eye lens 52 is arranged on the first optical axis BX1. The fly-eye lens 52 generates a surface light source image that divides the illumination light beam EL1 from the collimator lens 51 into a plurality of point light source images. The illumination light beam EL1 is generated from the surface light source image. At this time, the surface on the emission side of the fly-eye lens 52 that generates the point light source image is arranged in an optically conjugate manner with the pupil plane where the reflection surface of the first concave mirror 72 is located through various lenses from the fly-eye lens 52 via the illumination field aperture 55 to the first concave mirror 72 of the projection optical system PL described later. The optical axis of the condenser lens 53 provided on the emission side of the fly-eye lens 52 is arranged on the first optical axis BX1. The condenser lens 53 overlaps the light from each of the multiple point light source images formed on the emission side of the fly-eye lens 52 on the illumination field aperture 55, and illuminates the illumination field aperture 55 with a uniform illumination distribution. The illumination field aperture 55 has a rectangular opening portion of a trapezoid or a rectangle similar to the illumination area IR shown in FIG. 3, and the center of the opening portion is arranged on the first optical axis BX1. The opening portion of the illumination field aperture 55 is arranged to be optically conjugate with the illumination area IR on the mask M by the relay lens system (imaging system) 56, the polarization beam splitter PBS, and the 1/4 wavelength plate 41 provided in the optical path from the illumination field aperture 55 to the mask M. The relay lens system 56 is composed of a plurality of lenses 56a, 56b, 56c, and 56d arranged along the first optical axis BX1, and irradiates the illumination light beam EL1 after passing through the opening of the illumination field aperture 55 to the illumination area IR on the mask M via the polarization beam splitter PBS. A cylindrical lens 54 is provided on the emission side of the condenser lens 53 and adjacent to the illumination field aperture 55. The cylindrical lens 54 is a plano-convex cylindrical lens having a flat surface on the incident side and a convex cylindrical lens surface on the emission side. The optical axis of the cylindrical lens 54 is arranged on the first optical axis BX1. The cylindrical lens 54 converges the principal rays of the illumination light beam EL1 irradiating the illumination area IR on the mask M in the XZ plane and makes them parallel in the Y direction.

The polarization beam splitter PBS is arranged between the illumination optical module ILM and the center plane CL. The polarization beam splitter PBS reflects the linearly polarized light beam that becomes S polarized light with the wavefront division surface, and transmits the linearly polarized light beam that becomes P polarized light. Here, if the illumination light beam EL1 incident on the polarization beam splitter PBS is set as the linearly polarized light of S polarized light, the illumination light beam EL1 is reflected by the wavefront division surface of the polarization beam splitter PBS, passes through the 1/4 wavelength plate 41 to become circularly polarized light and illuminates the illumination area IR on the mask M. The projection light beam EL2 reflected by the illumination area IR on the mask M is converted from circularly polarized light to linear P polarized light by passing through the 1/4 wavelength plate 41 again, passes through the wavefront division surface of the polarization beam splitter PBS and heads toward the projection optical system PL. The polarization beam splitter PBS preferably reflects most of the illumination light beam EL1 incident on the wavefront division surface, and transmits most of the projection light beam EL2. The polarization separation characteristics on the wavefront separation plane of the polarization beam splitter PBS are expressed in terms of the extinction ratio. However, since the extinction ratio will also change due to the incident angle of the light toward the wavefront separation plane, the characteristics of the wavefront separation plane are designed in a way that does not affect the practical imaging performance and also takes into account the NA (numerical aperture) of the illumination beam EL1 and the projection beam EL2.

FIG. 5 is a diagram showing an enlarged view of the motion of the illumination light beam EL1 in the illumination region IR irradiated on the mask M and the projection light beam EL2 reflected by the illumination region IR in the XZ plane (a plane perpendicular to the first axis AX1). As shown in FIG. 5 , the illumination optical system IL intentionally sets each principal ray of the illumination light beam EL1 irradiated in the illumination region IR of the mask M to a non-telecentric state in the XZ plane (a plane perpendicular to the first axis AX1) and to a telecentric state in the YZ plane (parallel to the center plane CL) in such a manner that the principal ray of the projection light beam EL2 reflected by the illumination region IR of the mask M becomes telecentric (parallel). Such characteristics of the illumination light beam EL1 are imparted by the cylindrical lens 54 shown in FIG. 4 .

Specifically, after setting the intersection point Q2 (1/2 radius position) between a line passing from point Q1 in the circumferential center of the illumination region IR on the mask surface P1 and toward the first axis AX1 and a circle having a radius of 1/2 of the radius Rm of the mask surface P1, the curvature of the convex cylindrical lens surface of the cylindrical lens 54 is set so that each principal ray of the illumination light beam EL1 passing through the illumination region IR is directed toward the intersection point Q2 in the XZ plane. In this way, each principal ray of the projection light beam EL2 reflected in the illumination region IR is parallel (telecentric) to the straight line passing from the first axis AX1, point Q1, and the intersection point Q2 in the XZ plane.

Next, the multiple projection areas PA1 to PA6 projected and exposed by the projection optical system PL are described. As shown in FIG. 3 , the multiple projection areas PA1 to PA6 on the substrate P are configured corresponding to the multiple illumination areas IR1 to IR6 on the mask M. That is, the multiple projection areas PA1 to PA6 on the substrate P are separated by the center plane CL, and the first projection area PA1, the third projection area PA3 and the fifth projection area PA5 are configured on the substrate P on the upstream side of the conveying direction, and the second projection area PA2, the fourth projection area PA4 and the sixth projection area PA6 are configured on the substrate P on the downstream side of the conveying direction. Each projection area PA1 to PA6 becomes an elongated trapezoidal (rectangular) area having short sides and long sides extending along the width direction (Y direction) of the substrate P. At this time, each projection area PA1 to PA6 of the trapezoid becomes an area whose short side is located on the center plane CL side and whose long side is located on the outside. The first projection area PA1, the third projection area PA3 and the fifth projection area PA5 are configured at a predetermined interval in the width direction. In addition, the second projection area PA2, the fourth projection area PA4 and the sixth projection area PA6 are arranged at a predetermined interval in the width direction. At this time, the second projection area PA2 is arranged between the first projection area PA1 and the third projection area PA3 in the axial direction. Similarly, the third projection area PA3 is arranged between the second projection area PA2 and the fourth projection area PA4 in the axial direction. The fourth projection area PA4 is arranged between the third projection area PA3 and the fifth projection area PA5 in the axial direction. The fifth projection area PA5 is arranged between the fourth projection area PA4 and the sixth projection area PA6 in the axial direction. Each projection area PA1~PA6 is similar to each illumination area IR1~IR6, so that the triangular parts of the hypotenuse parts of the trapezoidal projection areas PA adjacent to each other in the Y direction overlap each other in the conveying direction of the substrate P. At this time, the projection area PA becomes a shape that makes the exposure amount in the overlapping area of the adjacent projection areas PA substantially the same as the exposure amount in the non-overlapping area. Moreover, 1st to 6th projection area|region PA1-PA6 are arrange|positioned so that the full width of the exposure area|region A7 exposed on the board|substrate P may be covered.

Here, in Figure 2, when observed in the XZ plane, the circumferential length of a circle on the mask M from the center point of the illumination area IR1 (and IR3, IR5) to the center point of the illumination area IR2 (and IR4, IR6) is set to be substantially equal to the circumferential length of a circle on the substrate P along the support surface P2 from the center point of the projection area PA1 (and PA3, PA5) to the center point of the projection area PA2 (and PA4, PA6).

A plurality of projection optical systems PL are provided corresponding to the plurality of projection areas PA1 to PA6 (for example, six in the first embodiment). A plurality of projection light beams EL2 reflected from the plurality of illumination areas IR1 to IR6 are incident on the plurality of projection optical systems (divided projection optical systems) PL1 to PL6, respectively. Each projection optical system PL1 to PL6 guides each projection light beam EL2 reflected by the mask M to each projection area PA1 to PA6, respectively. That is, the first projection optical system PL1 guides the projection light beam EL2 from the first illumination area IR1 to the first projection area PA1, and similarly, the second to sixth projection optical systems PL2 to PL6 guide each projection light beam EL2 from the second to sixth illumination areas IR2 to IR6 to the second to sixth projection areas PA2 to PA6. The plurality of projection optical systems PL1 to PL6 are separated by a center plane CL, and the first projection optical system PL1, the third projection optical system PL3, and the fifth projection optical system PL5 are arranged on the side (left side of FIG. 2) where the first, third, and fifth projection areas PA1, PA3, and PA5 are arranged. The first projection optical system PL1, the third projection optical system PL3 and the fifth projection optical system PL5 are arranged at a predetermined interval in the Y direction. In addition, the plurality of projection optical systems PL1 to PL6 are separated by the center plane CL, and the second projection optical system PL2, the fourth projection optical system PL4 and the sixth projection optical system PL6 are arranged on the side (right side of FIG. 2) where the second, fourth and sixth projection areas PA2, PA4 and PA6 are arranged. The second projection optical system PL2, the fourth projection optical system PL4 and the sixth projection optical system PL6 are arranged at a predetermined interval in the Y direction. At this time, the second projection optical system PL2 is arranged between the first projection optical system PL1 and the third projection optical system PL3 in the axial direction. Similarly, the third projection optical system PL3, the fourth projection optical system PL4 and the fifth projection optical system PL5 are arranged between the second projection optical system PL2 and the fourth projection optical system PL4, between the third projection optical system PL3 and the fifth projection optical system PL5, and between the fourth projection optical system PL4 and the sixth projection optical system PL6 in the axial direction. Moreover, the 1st projection optical system PL1, the 3rd projection optical system PL3, and the 5th projection optical system PL5 and the 2nd projection optical system PL2, the 4th projection optical system PL4, and the 6th projection optical system PL6 are arrange|positioned symmetrically when viewed from the Y direction.

Next, each projection optical system PL1 to PL6 will be described with reference to Fig. 4. In addition, since each projection optical system PL1 to PL6 has the same structure, the first projection optical system PL1 (hereinafter simply referred to as projection optical system PL) will be described as an example.

The projection optical system PL projects the image of the mask pattern in the illumination area IR (first illumination area IR1) on the mask M into the projection area PA on the substrate P. The projection optical system PL has the above-mentioned 1/4 wavelength plate 41, the above-mentioned polarization beam splitter PBS, and the projection optical module PLM in order from the incident side of the projection light beam EL2 from the mask M.

The quarter wavelength plate 41 and the polarization beam splitter PBS are used in common with the illumination optical system IL. In other words, the illumination optical system IL and the projection optical system PL share the quarter wavelength plate 41 and the polarization beam splitter PBS.

The projection light beam EL2 reflected by the illumination region IR becomes a telecentric state (a state in which each principal light beam is parallel to each other), and is incident on the projection optical system PL. The projection light beam EL2 reflected by the illumination region IR becomes circularly polarized light, and is converted from circularly polarized light to linearly polarized light (P polarized light) by the 1/4 wavelength plate 41, and then is incident on the polarization beam splitter PBS. The projection light beam EL2 incident on the polarization beam splitter PBS is incident on the projection optical module PLM after passing through the polarization beam splitter PBS.

The projection optical module PLM is provided corresponding to the illumination optical module ILM. That is, the projection optical module PLM of the first projection optical system PL1 projects the image of the mask pattern of the first illumination area IR1 illuminated by the illumination optical module ILM of the first illumination optical system IL1 onto the first projection area PA1 on the substrate P. Similarly, the projection optical modules LM of the second to sixth projection optical systems PL2 to PL6 project the images of the mask patterns of the second to sixth illumination areas IR2 to IR6 illuminated by the illumination optical modules ILM of the second to sixth illumination optical systems IL2 to IL6 onto the second to sixth projection areas PA2 to PA6 on the substrate P.

As shown in Fig. 4, the projection optical module PLM includes: a first optical system 61 for imaging the image of the mask pattern in the illumination area IR on the intermediate image plane P7; a second optical system 62 for re-imaging at least a portion of the intermediate image formed by the first optical system 61 on the projection area PA of the substrate P; and a projection field aperture 63 arranged on the intermediate image plane P7 forming the intermediate image. In addition, the projection optical module PLM includes a focus correction optical component 64, an image switching optical component 65, a magnification correction optical component 66, a rotation correction mechanism 67, and a polarization adjustment mechanism (polarization adjustment device) 68.

The first optical system 61 and the second optical system 62 are, for example, telecentric catadioptric optical systems that are deformed from a Dyson system. The optical axis of the first optical system 61 (hereinafter referred to as the second optical axis BX2) is substantially orthogonal to the center plane CL. The first optical system 61 includes a first deflecting component 70, a first lens group 71, and a first concave mirror 72. The first deflecting component 70 is a prism having a first reflection surface P3 and a second reflection surface P4. The first reflection surface P3 is a surface that reflects the projection light beam EL2 from the polarization beam splitter PBS and causes the reflected projection light beam EL2 to be incident on the first concave mirror 72 after passing through the first lens group 71. The second reflection surface P4 is a surface that the projection light beam EL2 reflected by the first concave mirror 72 is incident on after passing through the first lens group 71, and reflects the incident projection light beam EL2 toward the projection field aperture 63. The first lens group 71 includes various lenses, and the optical axes of the various lenses are arranged on the second optical axis BX2. The first concave mirror 72 is disposed on the pupil plane of the first optical system 61 , and is set to be optically conjugate with the plurality of point light source images generated by the fly-eye lens 52 .

The projection light beam EL2 from the polarization beam splitter PBS is reflected by the first reflection surface P3 of the first deflection member 70, and is incident on the first concave mirror 72 after passing through the upper half of the field of view of the first lens group 71. The projection light beam EL2 incident on the first concave mirror 72 is reflected by the first concave mirror 72, and is incident on the second reflection surface P4 of the first deflection member 70 after passing through the lower half of the field of view of the first lens group 71. The projection light beam EL2 incident on the second reflection surface P4 is reflected by the second reflection surface P4, and is incident on the projection field of view aperture 63 after passing through the focus correction optical component 64 and the image switching optical component 65.

The projection field aperture 63 has an opening that defines the shape of the projection area PA. That is, the shape of the opening of the projection field aperture 63 defines the substantial shape of the projection area PA. Therefore, when the shape of the opening of the illumination field aperture 55 in the illumination optical system IL is set to a trapezoid similar to the substantial shape of the projection area PA, the projection field aperture 63 can be omitted.

The second optical system 62 has the same structure as the first optical system 61, and is symmetrically arranged with the first optical system 61 separated by the intermediate image plane P7. The optical axis of the second optical system 62 (hereinafter referred to as the third optical axis BX3) is substantially orthogonal to the center plane CL and parallel to the second optical axis BX2. The second optical system 62 includes a second deflecting component 80, a second lens group 81, and a second concave mirror 82. The second deflecting component 80 has a third reflection surface P5 and a fourth reflection surface P6. The third reflection surface P5 is a surface that reflects the projection light beam EL2 from the projection field aperture 63 and causes the reflected projection light beam EL2 to be incident on the second concave mirror 82 after passing through the second lens group 81. The fourth reflection surface P6 is a surface that the projection light beam EL2 reflected by the second concave mirror 82 is incident on after passing through the second lens group 81, and reflects the incident projection light beam EL2 toward the projection area PA. The second lens group 81 includes various lenses, and the optical axes of the various lenses are arranged on the third optical axis BX3. The second concave mirror 82 is arranged on the pupil plane of the second optical system 62 , and is set to be optically conjugate with the plurality of point light source images formed on the first concave mirror 72 .

The projection light beam EL2 from the projection field aperture 63 is reflected by the third reflection surface P5 of the second deflection member 80, and is incident on the second concave mirror 82 after passing through the upper half field of view of the second lens group 81. The projection light beam EL2 incident on the second concave mirror 82 is reflected by the second concave mirror 82, and is incident on the fourth reflection surface P6 of the second deflection member 80 after passing through the lower half field of view of the second lens group 81. The projection light beam EL2 incident on the fourth reflection surface P6 is reflected by the fourth reflection surface P6, and is projected onto the projection area PA after passing through the magnification correction optical component 66. Thus, the image of the mask pattern in the illumination area IR is projected onto the projection area PA at the same magnification (×1).

The focus correction optical component 64 is arranged between the first deflection component 70 and the projection field aperture 63. The focus correction optical component 64 adjusts the focusing state of the image of the mask pattern projected onto the substrate P. The focus correction optical component 64 is a component obtained by, for example, making two wedge-shaped prisms reverse (in FIG. 4, reverse relative to the X direction) and overlapping them in a manner that the whole becomes a transparent parallel plate. The thickness of the parallel plate is made variable by sliding the pair of prisms along the inclined surface without changing the interval between the opposing surfaces. Thus, the effective optical path length of the first optical system 61 is finely adjusted, thereby finely adjusting the focusing state of the image of the mask pattern formed on the intermediate image plane P7 and the projection area PA.

The image switching optical component 65 is arranged between the first deflection component 70 and the projection field aperture 63. The image switching optical component 65 is adjusted in such a way that the image of the mask pattern projected onto the substrate P can be moved within the image plane. The image switching optical component 65 is composed of a transparent parallel plate glass that can be tilted within the XZ plane of FIG. 4 and a transparent parallel plate glass that can be tilted within the YZ plane of FIG. 4. By adjusting the tilt amounts of the two parallel plate glasses, the image of the mask pattern formed in the intermediate image plane P7 and the projection area PA can be slightly shifted in the X direction or the Y direction.

The optical component 66 for magnification correction is arranged between the second deflection component 80 and the substrate P. The optical component 66 for magnification correction is, for example, configured by coaxially arranging three lenses, namely, a concave lens, a convex lens, and a concave lens, at a predetermined interval, and the front and rear concave lenses are fixed, so that the middle convex lens moves in the direction of the optical axis (main light). As a result, the image of the mask pattern formed in the projection area PA is isotropically enlarged or reduced only slightly while maintaining a telecentric imaging state. In addition, the optical axis of the three lens groups constituting the optical component 66 for magnification correction is tilted in the XZ plane in a manner parallel to the main light of the projection light beam EL2.

The rotation correction mechanism 67 is a mechanism that slightly rotates the first deflection member 70 around an axis parallel to the Z axis by, for example, an actuator (not shown). The rotation correction mechanism 67 can slightly rotate the image of the mask pattern formed on the intermediate image plane P7 within the intermediate image plane P7 by rotating the first deflection member 70.

The polarization adjustment mechanism 68 is a mechanism for adjusting the polarization direction by, for example, rotating the quarter wavelength plate 41 around an axis perpendicular to the plate surface by an actuator (not shown). The polarization adjustment mechanism 68 can adjust the illumination of the projection light beam EL2 projected onto the projection area PA by rotating the quarter wavelength plate 41.

In the projection optical system PL configured in this way, the projection light beam EL2 from the mask M is emitted from the illumination region IR in a telecentric state (a state in which each principal light beam is parallel to each other), and enters the first optical system 61 after passing through the 1/4 wavelength plate 41 and the polarization beam splitter PBS. The projection light beam EL2 entering the first optical system 61 is reflected by the first reflection surface (plane mirror) P3 of the first deflection member 70 of the first optical system 61, and is reflected by the first concave mirror 72 after passing through the first lens group 71. The projection light beam EL2 reflected by the first concave mirror 72 passes through the first lens group 71 again, and is reflected by the second reflection surface (plane mirror) P4 of the first deflection member 70, and enters the projection field aperture 63 after passing through the focus correction optical member 64 and the image switching optical member 65. The projection light beam EL2 passing through the projection field aperture 63 is reflected by the third reflection surface (plane mirror) P5 of the second deflection member 80 of the second optical system 62, and is reflected by the second concave mirror 82 after passing through the second lens group 81. The projection light beam EL2 reflected by the second concave mirror 82 passes through the second lens group 81 again, is reflected by the fourth reflection surface (plane mirror) P6 of the second deflection member 80, and is incident on the magnification correction optical member 66. The projection light beam EL2 emitted from the magnification correction optical member 66 is incident on the projection area PA on the substrate P, and the image of the mask pattern appearing in the illumination area IR is projected onto the projection area PA at the same magnification (×1).

In the present embodiment, although the second reflection surface (plane mirror) P4 of the first deflection member 70 and the third reflection surface (plane mirror) P5 of the second deflection member 80 are surfaces inclined at 45° relative to the center plane CL (or the optical axes BX2, BX3), the first reflection surface (plane mirror) P3 of the first deflection member 70 and the fourth reflection surface (plane mirror) P6 of the second deflection member 80 are set to an angle other than 45° relative to the center plane CL (or the optical axes BX2, BX3). In FIG5 , when the angle formed by the straight line passing through the point Q1, the intersection point Q2, the first axis AX1 and the center plane CL is set to θs°, the angle α° (absolute value) of the first reflection surface P3 of the first deflection member 70 relative to the center plane CL (or the optical axis BX2) is determined to be the relationship of α°=45°+θs°/2. Similarly, when the angle between the main light ray of the projection light beam EL2 passing through the center point in the projection area PA in the circumferential direction of the outer surface of the substrate support tube 25 and the center plane CL in the ZX plane is set to εs°, the angle β° (absolute value) of the fourth reflection surface P6 of the second deflection component 80 relative to the center plane CL (or the second optical axis BX2) is determined to be β°=45°+εs°/2.

<Mask and Mask Support Cylinder>

Next, the structure of the cylindrical wheel (mask holding cylinder) 21 and the mask M of the mask holding mechanism 11 in the exposure device U3 of the first embodiment will be described using Figures 6 and 7. Figure 6 is a perspective view showing the schematic structure of the cylindrical wheel 21 and the mask M formed on the outer circumferential surface thereof. Figure 7 is a development view showing the schematic structure of the mask surface P1 when the outer circumferential surface of the cylindrical wheel 21 is developed into a plane.

In the present embodiment, the photomask M is set as a reflective sheet photomask. Although it is applicable whether it is wound on the outer peripheral surface of the cylindrical wheel 21 or when the cylindrical wheel 21 is composed of a metal cylindrical substrate and a reflective mask pattern is directly formed on the outer peripheral surface of the cylindrical substrate, for the sake of simplicity, the latter case is described here. As shown in the previous Figure 3, the photomask M formed on the outer peripheral surface (diameter φ) of the cylindrical wheel 21, that is, the photomask surface P1, is composed of a pattern forming area A3 and a non-pattern forming area (shading band area) A4. The photomask M shown in Figures 6 and 7 corresponds to the pattern forming area A3 in the exposure area A7 projected onto the substrate P in Figure 3 via each projection area PA1~PA6 of the projection optical system PL1~PL6. Although the mask M (pattern forming area A3) is formed in the substantially entire area of the outer peripheral surface of the cylindrical wheel 21 in the circumferential direction, when the width (length) in the direction parallel to the first axis AX1 (Y direction) is set to L, it is smaller than the length La of the outer peripheral surface of the cylindrical wheel 21 in the direction parallel to the first axis AX1 (Y direction). In addition, in the case of the present embodiment, the mask M is not closely arranged within the 360° range of the outer peripheral surface of the cylindrical wheel 21, but is provided with a blank portion 92 of a predetermined size in the circumferential direction. Therefore, the two ends of the blank portion 92 in the circumferential direction correspond to the terminal end and the starting end of the mask M (pattern forming area A3) in the scanning exposure direction.

In addition, in FIG6 , an axis SF coaxial with the first axis AX1 is provided on both end surfaces of the cylindrical wheel 21. The axis SF supports the cylindrical wheel 21 via bearings provided at specified positions in the exposure device U3. The bearings are of a contact type using metal balls or needles, or a non-contact type such as a static pressure gas bearing. Furthermore, a grating (encoder scale) for measuring the rotation angle position of the cylindrical wheel 21 (mask M) with high precision can be formed in the entire circumferential direction in each end region on the outer side of the outer side of the region of the mask M in the Y direction parallel to the first axis AX1 on the outer peripheral surface (mask surface P1) of the cylindrical wheel 21. A scale circular plate engraved with a grating for measuring the rotation angle position can also be fixed coaxially with the axis SF.

Here, FIG. 7 shows the state in which the outer circumference of the cylindrical wheel 21 of FIG. 6 is cut off by the cutting line 94 in the margin portion 92 and then unfolded. In addition, in the following description, the direction orthogonal to the Y direction in the state in which the outer circumference is unfolded is set as the θ direction. As shown in FIG. 7, since the diameter is φ, the circumference ratio is set to π, and the total circumferential length of the mask surface P1 is πφ. In addition, relative to the total length La of the mask surface P1 in the direction parallel to the first axis AX1, the length L of the mask M (pattern forming area A3) in the Y direction parallel to the first axis AX1 is formed with L≤La, and is formed with a length Lb in the θ direction. The length obtained by subtracting the length Lb from the total circumferential length πφ of the mask surface P1 is the total size of the margin portion 92 in the θ direction. Alignment marks for positioning the mask M are also formed at various scattered positions in the Y direction within the margin portion 92.

Here, the mask M shown in FIG. 7 is a mask for forming a pattern corresponding to one of the display panels used in a liquid crystal display, an organic EL display, etc. In this case, as the pattern formed on the mask M, there are patterns of electrodes or wirings for TFTs that drive each pixel of the display screen of the display panel, patterns of each pixel of the display screen of the display device, and patterns of color filters and black matrices of the display device. As shown in FIG. 7, on the mask M (pattern forming area A3), there is a display screen area DPA that forms a pattern corresponding to the display screen of the display panel, and a peripheral circuit area TAB that is arranged around the display screen area DPA and forms a pattern of a circuit for driving the display screen.

The size of the display screen area DPA on the mask M corresponds to the size of the display portion of the display panel to be manufactured (the inch size of the diagonal length Le). When the projection magnification of the projection optical system PL shown in Figures 2 and 4 is equal (×1), the actual size of the display screen area DPA on the mask M (diagonal length Le) becomes the inch size of the actual display screen. In the present embodiment, the display screen area DPA is a rectangle with a long side Ld and a short side Lc, and the length ratio (aspect ratio) of the long side Ld to the short side Lc is Ld:Lc=16:9 or Ld:Lc=2:1 in a typical example. The aspect ratio of 16:9 is the aspect ratio of the screen used for the so-called high-definition size (wide size). In addition, the aspect ratio of 2:1 is the aspect ratio of the screen called the display (scope) size, and is the aspect ratio used for the ultra-high-definition size of 4K2K in the TV screen. For example, if the display panel has an aspect ratio of 16:9 and a screen size of 50 inches (Le=127 cm), the long side Ld of the display screen area DPA on the mask M is approximately 110.7 cm, and the short side Lc is approximately 62.3 cm. In addition, if the screen size is the same (50 inches) and the aspect ratio is 2:1, the long side Ld of the display screen area DPA is approximately 113.6 cm, and the short side Lc is approximately 56.8 cm.

As shown in FIG. 7 , when a mask M for a display panel (including a display screen area DPA and a peripheral circuit area TAB) is formed on the outer peripheral surface of a cylindrical wheel 21, it is preferably configured in such a manner that the direction of the long side Ld of the display screen area DPA becomes the θ direction (the circumferential direction of the cylindrical wheel 21). This is because it is not necessary to make the diameter φ of the cylindrical wheel 21 too small, nor is it necessary to make the length La of the first axis AX1 direction of the cylindrical wheel 21 too large. Here, an example of the size (Lb×L) of the mask M including the width dimension of the peripheral circuit area TAB is given. Although the width dimension of the peripheral circuit area TAB may vary depending on the circuit structure, the total width of the peripheral circuit area TAB in the Y direction located at both ends of the display screen area DPA in the Y direction in FIG. 7 can be set to 10% of the length Lc of the display screen area DPA in the Y direction, and the total width of the peripheral circuit area TAB in the θ direction located at both ends of the display screen area DPA in the θ direction can be set to 10% of the length Ld of the display screen area DPA in the θ direction.

In this case, in a 50-inch display panel with an aspect ratio of 16:9, the long side Lb of the mask M is 121.76 cm and the short side L is 68.49 cm. Since the size of the blank portion 92 in the θ direction is greater than zero, the diameter φ of the cylindrical wheel 21 is greater than 38.76 cm based on the calculation of φ≥Lb/π. Therefore, in order to scan and expose the pattern of a 50-inch display panel with an aspect ratio of 16:9 onto the substrate P, a cylindrical wheel 21 with a diameter φ of greater than 38.76 mm and a length La of the mask surface P1 in a direction parallel to the first axis AX1 greater than the short side L (68.49 cm) is required. In this case, the ratio L/φ of the diameter φ to the short side L of the mask M is approximately 1.77. In addition, if it is assumed that the total width of the peripheral circuit area TAB in the θ direction is 20% of the length Ld of the display screen area DPA in the θ direction, the long side Lb of the mask M is 132.83 cm, the short side L is 68.49 cm, the diameter φ of the cylindrical wheel 21 is greater than 42.28 cm, and the ratio L/φ of the diameter φ to the short side L of the mask M is approximately 1.62.

Under the same conditions, if it is a 50-inch display panel with an aspect ratio of 2:1, the long side Lb of the mask M is 124.96 cm and the short side L is 62.48 cm. Therefore, the diameter φ of the cylindrical wheel 21 is greater than 39.78 cm based on the calculation of φ≥Lb/π. Therefore, in order to scan and expose the pattern of a 50-inch display panel with an aspect ratio of 2:1 onto the substrate P, a cylindrical wheel 21 with a diameter φ greater than 39.78 cm and a length La of the mask surface P1 in a direction parallel to the first axis AX1 greater than the short side L (62.48 cm) is required. In this case, the ratio L/φ of the diameter φ to the short side L of the mask M is approximately 1.57. In addition, if it is assumed that the total width of the peripheral circuit area TAB in the θ direction is 20% of the length Ld of the display screen area DPA in the θ direction, the long side Lb of the mask M is 136.31 cm, the short side L is 62.48 cm, the diameter φ of the cylindrical wheel 21 is greater than 43.39 cm, and the ratio L/φ of the diameter φ to the short side L of the mask M is approximately 1.44.

As shown in FIG7 , when a mask M having a single display panel pattern is arranged on the outer peripheral surface of a cylindrical wheel (mask holding cylinder) 21, the relationship between the length L of the mask M in the Y direction orthogonal to the scanning exposure direction and the diameter φ of the mask surface P1 falls within the range of 1.3≤L/φ≤3.8. However, when the arrangement of the mask M shown in FIG7 is rotated 90° in FIG7 , and the long side Lb of the mask M is set in the Y direction and the short side L is set in the θ direction, the above relationship is deviated. For example, in the case of a 50-inch display panel with a previous aspect ratio of 16:9, if the width of the peripheral circuit area TAB in the θ direction is set to 10% of the length Ld of the display screen area DPA, since the long side Lb of the mask M is 121.76 cm and the short side L is 68.49 cm, the minimum value of the length L of the mask surface P1 in the direction parallel to the first axis AX1 is Lb (121.76 cm), and the diameter φ of the cylindrical wheel 21 is calculated based on φ≥L/π, which is greater than 21.80 cm. Therefore, the ratio Lb/φ of the diameter φ to the length Lb of the mask M in the direction parallel to the first axis AX1 is approximately 5.59. Similarly, in the case of a 50-inch display panel with an aspect ratio of 2:1, since the long side Lb of the mask M is 124.96 cm and the short side L is 62.48 cm, the minimum value of the length L of the mask surface P1 in the direction parallel to the first axis AX1 is Lb (124.96 cm), and the diameter φ of the cylindrical wheel 21 is calculated based on φ≥L/π, which is greater than 19.89 cm. Therefore, the ratio Lb/φ of the diameter φ to the length Lb of the mask M in the direction parallel to the first axis AX1 is approximately 6.28.

Thus, even if the size (Lb×L) of the mask M is the same, the value of the ratio L/φ (or Lb/φ) will vary greatly depending on the directions of its long side and short side. A large ratio L/φ (or Lb/φ) indicates that the diameter φ of the cylindrical wheel 21 is small and the curvature of the mask surface P1 is steep. Therefore, in order to maintain the fidelity of the pattern transfer, the width of the illumination area IR or the projection area PA in the scanning exposure direction Xs shown in FIG. 3 must be set narrower. Alternatively, the length of the cylindrical wheel 21 in the direction parallel to the first axis AX1 needs to be doubled to further increase the number of the plurality of projection optical systems PL (illumination optical systems IL) arranged in the Y direction. On the other hand, if the ratio L/φ (or Lb/φ) is small, the length of the mask M on the cylindrical wheel 21 in the direction parallel to the first axis AX1 is small, for example, only about half of the six projection areas PA1 to PA6 in FIG. 3 are used, or the diameter φ of the cylindrical wheel 21 is too large, resulting in the size of the margin 92 in the θ direction shown in FIG. 6 and FIG. 7 becoming larger than required. For the above reasons, by setting the outer dimension condition of the cylindrical wheel (mask holding cylinder) 21 to the relationship of 1.3≤L/φ≤3.8, it is possible to effectively implement a precision exposure operation using the mask M formed with a display panel pattern, and to improve productivity.

In the examples shown in FIG. 6 and FIG. 7 , although the photomask M having a single-sided display panel pattern is supported on the outer circumferential surface (photomask surface P1) of the cylindrical wheel (photomask holding cylinder) 21, there is also a case where multiple display panel patterns are formed on the photomask surface P1. Several examples of this case are described with reference to FIG. 8 to FIG. 10 .

FIG8 is an expanded view showing a schematic structure in which three photomasks M1 of the same size are arranged on the photomask surface P1 along the circumferential length direction (θ direction) of the cylindrical wheel 21. FIG9 is an expanded view showing a schematic structure in which four photomasks M2 of the same size are arranged on the photomask surface P1 along the circumferential length direction (θ direction) of the cylindrical wheel 21. FIG10 is an expanded view showing a schematic structure in which the photomask M2 shown in FIG9 is rotated 90°, two photomasks M2 are arranged along the Y direction on the photomask surface P1, and then two groups are arranged along the circumferential length direction (θ direction) of the cylindrical wheel 21. Since multiple (here, three or four) display panels of the same size on the substrate P are exposed in one rotation of the cylindrical wheel 21, the examples shown in FIGS. 8 to 10 are referred to as multi-faceted photomasks M. In addition, as shown in FIG8, the entire area on the mask surface P1 to be scanned and exposed on the substrate P via the projection optical system PL is set as a mask M in conjunction with FIG7, and the masks M1 (M2 in FIG9 and FIG10) to be the display panel in the mask M are arranged at a predetermined interval Sx along the scanning exposure direction (θ direction). In each mask M1 (M2 in FIG9 and FIG10), as in FIG7, a display screen area DPA with a diagonal length Le and a peripheral circuit area TAB surrounding it are included.

First, the example shown in FIG8 will be described in detail as follows. In FIG8 , the largest rectangle is the outer peripheral surface of the cylindrical wheel 21, namely the mask surface P1. When the cutting line 94 is taken as the origin in the θ direction, the mask surface P1 has a length πφ in the θ direction within the range of rotation angles from 0° to 360°, and has a length La in the Y direction parallel to the first axis AX1. The area indicated by the dotted line on the inner side of the mask surface P1 is the mask M corresponding to the entire area to be exposed on the substrate P (exposure area A7 in FIG3 ). The three masks M1 arranged along the θ direction in the mask M are arranged in such a way that the long side direction of the display screen area DPA is in the Y direction and the short side direction is in the θ direction. In addition, within the interval Sx adjacent to each mask M1 along the θ direction, alignment marks (mask marks) 96 for the position of the mask M (or M1) on the specific cylindrical wheel 21 are discretely provided at three locations in the Y direction. These mask marks 96 are detected by a mask alignment optical system (not shown) arranged opposite to the outer peripheral surface (mask surface P1) at a predetermined position in the circumferential direction of the cylindrical wheel 21. The exposure device U3 measures the positional deviation of the entire cylindrical wheel 21 or each mask M1 in the rotational direction (θ direction) and the positional deviation in the Y direction based on the position of each mask mark 96 detected by the mask alignment optical system.

Generally speaking, when forming a device for a display panel on a substrate P, multiple layers need to be stacked. Therefore, the exposure device transfers the alignment mark (substrate mark) used to specify the position on the substrate P where the pattern of the mask M (or M1) is exposed, together with the mask M (or M1), to the substrate P. In FIG8 , such substrate marks 96a are formed at three locations separated in the θ direction and at both ends of each mask M1 in the Y direction. The width of the area on the mask (or substrate P) occupied by the substrate mark 96a in the Y direction is about several mm. Therefore, the Y-direction length L of the mask M to be exposed on the mask surface P1 on the substrate P becomes the sum of the Y-direction dimensions of each mask M1 and the Y-direction dimensions of the area of the substrate mark 96a ensured on both sides of the Y direction of each mask M1.

In addition, if the length of the sum of the size of each mask M1 in the θ direction and the size of each interval Sx in the Y direction is set to Px, the length Lb of the mask M in the θ direction on the mask surface P1 becomes Lb=3Px. As shown in the previous FIG. 7, when configuring the mask M corresponding to a single display panel, it is preferable to set a blank portion 92 of a specified length. However, as shown in FIG. 8, when configuring a plurality of masks M1 by setting an interval Sx in the θ direction, the length of the blank portion 92 in the θ direction can be made zero. That is, the length of each mask M1 in the θ direction is naturally determined according to the size of the display panel, and the minimum size required as the interval Sx is also predetermined. Therefore, it is sufficient to set the diameter φ of the cylindrical wheel 21 to satisfy the relationship of φ=3Px/π. On the contrary, if the range of the diameter φ of the cylindrical wheel 21 that can be mounted on the exposure device U3 has been roughly determined, it can be adjusted by changing (increasing) the size of the interval Sx.

Here, an example of the specific size of the mask M shown in FIG8 is described. In FIG8, it is assumed that the diagonal length Le of the display screen area DPA of the mask M1 is 32 inches (81.28 cm), the dimensions of the Y direction and the θ direction of the peripheral circuit area TAB are about 10% of the size of the display screen area DPA, and the dimension of the Y direction of the area where the substrate mark 96a is formed is 0.5 cm (1 cm in total on both sides). If the display panel has an aspect ratio of 16:9, the short side dimension of the mask M1 is 48.83 cm and the long side dimension is 77.93 cm. If the display panel has an aspect ratio of 2:1, the short side dimension of the mask M1 is 43.83 cm and the long side dimension is 79.97 cm. When the size of the margin 92 is set to zero and three masks M1 and three intervals Sx are arranged in the θ direction so as to satisfy Lb=πφ=3Px, and the length of the mask M1 in the θ direction is set to Lg, the interval Sx is obtained by Sx=(Lb-3Lg)/3.

Therefore, when one of the mask M1 for display panels with an aspect ratio of 16:9 and the mask M1 for display panels with an aspect ratio of 2:1 is configured to be arranged on the mask surface P1 of the cylindrical wheel 21 with the same diameter, the diameter φ of the cylindrical wheel 21 can be set to about 43 cm. In this case, in the display panel with an aspect ratio of 16:9, the interval Sx between the masks M1 can be set to 1.196 cm, and in the display panel with an aspect ratio of 2:1, the interval Sx between the masks M1 can be set to 5.045 cm.

Since the Y-direction length L of the mask M on the mask surface P1 is the sum of the Y-direction dimension of the mask M1 and the Y-direction dimension (1 cm) of the formation area of the substrate mark 96a, L = 78.93 cm in the mask M for a display panel with an aspect ratio of 16:9, and L = 80.97 cm in the mask M for a display panel with an aspect ratio of 2:1. Therefore, in the case of the cylindrical wheel 21 for a display panel with an aspect ratio of 16:9, the ratio of the diameter φ (43 cm) of the cylindrical wheel 21 to the Y-direction length L of the mask M is L/φ = 1.84, and in the case of the cylindrical wheel 21 for a display panel with an aspect ratio of 2:1, it is L/φ = 1.88. In either case, the ratio L/φ falls within the range of 1.3 to 3.8.

In addition, in the case of exposing a pattern of a display panel with an aspect ratio of 16:9 onto the substrate P, and in the case of exposing a pattern of a display panel with an aspect ratio of 2:1 onto the substrate P, if the dimension of the interval Sx in the θ direction on the substrate P is controlled to the minimum required limit, it is naturally necessary to change the diameter φ of the cylindrical wheel 21. For example, when the interval Sx is set to 2 cm, the diameter φ of the cylindrical wheel 21 formed with the mask M1 for the display panel with an aspect ratio of 16:9 is φ≥43.77 cm from the relationship of πφ＝3(Lg+Sx). On the other hand, the diameter φ of the cylindrical wheel 21 formed with the mask M1 for the display panel with an aspect ratio of 2:1 is φ≥40.1 cm. In this case, if the cylindrical wheel 21 is used for a display panel with an aspect ratio of 16:9, the ratio L/φ=1.80, and if the cylindrical wheel 21 is used for a display panel with an aspect ratio of 2:1, the ratio L/φ=2.02, both falling within the range of 1.3 to 3.8.

In addition, in the case where the diameter φ of the cylindrical wheel 21 (mask M) to be installed on the exposure device U3 changes, a mechanism is provided on the exposure device U3 to offset the Z-direction position of the first axis AX1 of the cylindrical wheel 21 by about 1/2 of the difference in its diameter φ. In the above example, since the difference in diameter φ is 3.67 cm, the first axis AX1 (axis SF) of the cylindrical wheel 21 is offset by about 1.835 cm in the Z direction and supported. Furthermore, when the offset of the first axis AX1 of the cylindrical wheel 21 in the Z direction is large, it is necessary to change the cylindrical lens 54 shown in FIG. 4 to a cylindrical lens having a curvature of a convex cylindrical surface that satisfies the lighting conditions shown in FIG. 5, adjust the angle α° of the first reflecting surface (plane mirror) P3 of the first deflection component 70, and tilt the polarization beam splitter PBS and the 1/4 wavelength plate 41 slightly in the XZ plane as a whole.

As described above, as shown in FIG8 , on the mask M (including three masks M1) formed on the cylindrical wheel 21, a plurality of substrate marks 96a are provided along the θ direction (scanning exposure direction) along with the pattern (mask M1) for the display panel transferred to the substrate P. Therefore, when the plurality of substrate marks 96a are sequentially transferred to the substrate P together with the pattern (mask M1) for the display panel by the exposure device U3, various problems during exposure can be confirmed. For example, the substrate mark 96a transferred to the substrate P can be used to identify the position of a defect (such as foreign matter adhesion) generated on the substrate P, or to measure various bias errors such as the patterning error of the mask, the focus error, and the overlap error during overlapping exposure. In addition to being used for the management of the mask as a whole, the measured bias error is also used for the position management of each mask M1 on the cylindrical mask 21, and the position management (correction) of the pattern (mask M1) of each display panel transferred to the substrate P.

FIG9 shows an example in which four masks M2 for a display panel having an aspect ratio of 2:1 are arranged along the θ direction and arranged on the mask surface P1 of the cylindrical wheel 21 in such a manner that the Y direction is the long side of the display screen area DPA. A spacing Sx is provided on the side (long side) in the θ direction of each mask M2, and the mask mark 96 and the substrate mark 96a are also provided in the same manner as in FIG8 . In this case, the total length πφ (=Lb) of the mask surface P1 in the circumferential direction (θ direction) is πφ=4Px=4(Lg+Sx). Here, the screen size of the display screen area DPA is set to 24 inches (Le = 60.96cm), the total width of the peripheral circuit area TAB in the θ direction is set to 10% of the length of the display screen area DPA in the θ direction, the total width of the peripheral circuit area TAB in the Y direction is set to 20% of the length of the display screen area DPA in the Y direction, and the total width of the formation area of the substrate mark 96a respectively arranged at the two ends of the mask M2 in the Y direction in the Y direction is set to 1cm.

In this case, since the size of the display screen area DPA is 54.52 cm on the long side and 27.26 cm on the short side, the total length L in the Y direction of the exposure mask M on the mask surface P1 includes the formation area of the mask M2 and the substrate mark 96a, which is L=66.43 cm. In addition, since the length Lg in the θ direction of the mask M2 on the mask surface P1 is Lg=29.99 cm, when the interval Sx is set to 1 cm, the diameter φ of the mask M (cylindrical wheel 21) is greater than 39.46 cm due to πφ≥4Px. Therefore, as shown in FIG. 9, when the four surfaces of the mask M2 for the display panel with an aspect ratio of 2:1 are set on the cylindrical wheel 21, the ratio L/φ is 1.67, which also falls within the range of 1.3 to 3.8.

FIG. 10 shows an example of a case where the mask M2 shown in FIG. 9 is rotated 90° so that the long side is arranged in the θ direction, and a total of four masks are arranged on the mask surface P1 in a manner of two masks arranged in the θ direction and two masks arranged in the Y direction. In addition, here, a formation area for the substrate mark 96a is provided between the two masks M arranged in the Y direction. Therefore, if the total width in the Y direction of the formation area of the substrate mark 96a is set to 2 cm, the total length (short side) L in the Y direction of the mask M formed on the mask surface P1 is 61.98 cm, the total length (long side) πφ in the θ direction of the mask M is 132.86 cm, the diameter φ of the mask M (cylindrical mask 21) is greater than 42.29 cm, and the ratio L/φ is 1.47.

In addition, when four masks M2 are arranged as shown in Figures 9 or 10, the diameter φ of the cylindrical wheel 21 and the Y-direction dimension La of the mask surface P1 can be fixed by adjusting the interval Sx. In the cases of Figures 9 and 10, the Y-direction length L of the mask M is larger in the case of Figure 9, L=66.43 cm, and the diameter φ of the cylindrical wheel 21 (mask M) is larger in the case of Figure 10, φ≥42.29 cm. Therefore, if a cylindrical wheel 21 is used in which the Y-direction dimension La of the outer peripheral surface (mask surface P1) is La≥66.43 cm and the diameter φ is φ≥42.3 cm, the mask M2 can be arranged on all four sides regardless of the configuration of Figures 9 and 10. In this case, the ratio L/φ is 1.57, which also falls within the range of 1.3 to 3.8.

As shown in FIGS. 8 to 10, it is possible to arrange mask patterns (masks M, M1, M2) for display devices on the mask surface P1 according to various arrangement rules. In contrast, by making the relationship between the length L of the mask surface P1 (peripheral surface) of the cylindrical wheel (mask holding cylinder) 21 in the direction (Y direction) orthogonal to the scanning exposure direction (θ direction) and the diameter φ of the cylindrical wheel 21 satisfy 1.3≤L/φ≤3.8, as shown in FIGS. 8 to 10, even in the case of arranging mask patterns (masks M1, M2) for display panels of multiple sizes, the mask patterns can be arranged with the gap (interval Sx) reduced.

In addition, by making the cylindrical wheel 21 satisfy the relationship of 1.3≤L/φ≤3.8, it is possible to suppress the increase in the number of illumination optical systems IL and projection optical systems PL while suppressing the increase in the size of the device. In other words, the cylindrical wheel 21 becomes slender, which can suppress the increase in the number of illumination optical systems IL and projection optical systems PL. In addition, the diameter φ of the cylindrical wheel 21 becomes larger, so that the Z-direction dimension of the device can be suppressed from increasing.

Here, as shown in FIG. 7, when a mask M with one side for a display panel with an aspect ratio of 2:1 is formed on the entire outer peripheral surface (mask surface P1) of the cylindrical wheel 21, it is assumed that the dimension of the margin 92 in the θ direction in FIG. 6 and FIG. 7 is zero, and the dimension La of the mask surface P1 in the Y direction (first axis AX1 direction) is La=L. In addition, as previously described, the peripheral circuit area TAB arranged around the screen display area DPA is equivalent to about 20% of the screen display area DPA. However, the size ratio of the peripheral circuit area TAB will change depending on which part of the screen display area DPA is arranged as the terminal part of the circuit due to the actual pattern specifications and design. Therefore, although it cannot be accurately specified, it is assumed that the total width of the peripheral circuit area TAB adjacent to the short side of the screen display area DPA will increase in the direction where the aspect ratio of the mask M becomes larger, and it is assumed to be about 20% of the long side Ld of the screen display area DPA. In addition, the total width of the peripheral circuit area TAB adjacent to the long side of the screen display area DPA is assumed to be about 0 to 10% of the short side Lc of the screen display area DPA. Under this assumption, when the screen display area DPA is a 50-inch display panel with an aspect ratio of 2:1, the long side Ld of the screen display area DPA is 113.59 cm and the short side Lc is 56.8 cm. Therefore, the length Lb (=πφ) of the mask M in the θ direction in Figure 7 is 136.31 cm, the diameter φ of the cylindrical wheel 21 (mask M) is 43.39 cm, the length L (=La) in the Y direction is 56.8 to 62.48 cm, and the ratio of the length L to the diameter φ is 1.30 to 1.44. In this way, when the mask for a display panel with a large aspect ratio is formed on the entire outer peripheral surface (mask surface P1) of the cylindrical wheel 21 in a manner of configuring one side, the ratio L/φ becomes the minimum value of 1.3. In addition, when the aspect ratio of the screen display area DPA is 2:1, if the mask M only includes the width of the peripheral circuit area TAB in the long side direction and is 20% larger, the aspect ratio (Lb/L) of the mask M configured on one side shown in Figure 7 is 2.4, and since Lb=πφ, the derived ratio L/φ=π/2.4≒1.30.

In addition, when the mask M in FIG. 7 is rotated 90° and arranged on the substantially entire surface of the mask surface P1 of the cylindrical wheel 21, as described above, the ratio L/φ becomes too large. As described under the above conditions, when the aspect ratio of the screen display area DPA is 2:1, if the mask M arranged on one side is only 20% larger than the width of the peripheral circuit area TAB in the long side direction, and the dimension of the margin 92 in the θ direction is zero, then L/Lb(πφ)＝2.4/1, and the ratio L/φ is 7.54. In this case, if the mask M arranged on one side is used for the 50-inch display panel in the previous example, the length L in the Y direction is 136.31 cm, the length Lb(πφ) in the θ direction is 56.8 cm, and the diameter φ of the cylindrical wheel 21 (mask M) is 18.1 cm. In this way, the ratio L/φ changes greatly when the long side direction of the mask M is set to the θ direction and when it is set to the Y direction.

When the diameter of the cylindrical wheel 21 of the projection optical system PL of the exposure device U3 changes significantly, especially when the diameter φ becomes smaller, the distortion error caused by projection and the change point of the projection image plane caused by the arc become larger, so it is difficult to expose a good projection image to the substrate P. In this case, for example, as shown in FIG. 11, two masks M2 with the long side direction set to the Y direction for the display panel of the screen display area DPA with an aspect ratio of 2:1 can be arranged in the θ direction.

In FIG. 11 , the two masks M2 respectively include a screen display area DPA with an aspect ratio of 2:1, and a peripheral circuit area TAB arranged on both sides of the screen display area DPA in the Y direction. The total Y-direction width of the peripheral circuit area TAB is set to 20% of the long side dimension Ld of the screen display area DPA, and a gap Sx is provided on the right adjacent side of the mask M2. If it is assumed that there is no substrate mark 96a or mask mark 96 arranged around the mask M2, the Y-direction dimension L of the entire mask M (mask surface P1) including the two masks M2 and the gap Sx is L=1.2·Ld, and the θ-direction dimension πφ (Lb) is πφ=2(Lc+Sx). When the aspect ratio Asp of the screen display area DPA is set to Asp=Ld/Lc, the ratio L/φ is expressed as follows.

L/φ＝0.6·π·Asp·Lc/(Lc+Sx)

Here, if the interval Sx is set to zero, the ratio L/φ is L/φ=0.6·π·Asp. When two masks M2 for a display panel with an aspect ratio of 2:1 are arranged in the direction shown in FIG. 11, the ratio L/φ of the diameter φ of the cylindrical wheel 21 (mask surface P1) and the length L (=La) in the direction of the first axis AX1 is 3.77 (about 3.8). In this case, if the screen display area DPA (2:1) is 50 inches, the diameter φ is 36.16 cm and the length L (La) is 136.31 cm. Similarly, when the mask M2 shown in FIG. 11 is used for a display panel with an aspect ratio of 16:9, if the interval Sx is set to zero, the ratio L/φ becomes 3.35 due to the relationship of L/φ=0.6·π·Asp. In this case, if the screen display area DPA (16:9) is 50 inches, the diameter φ is 39.64 cm and the length L (La) is 132.83 cm.

As described above, when the light mask M is arranged in such a manner that the short side direction of the screen display area DPA faces the circumferential direction (θ direction) of the cylindrical wheel 21 and the long side direction faces the direction (Y direction) of the first axis AX1 of the cylindrical wheel 21, by arranging two or more identical light masks M2 in the θ direction, the ratio L/φ can be set to 3.8 or less. In addition, if n light masks M2 shown in FIG. 11 are arranged in the θ direction under the same conditions, the above relationship formula representing the ratio L/φ is as follows.

L/φ＝1.2·π·Asp·Lc/n(Lc+Sx)

According to this relational expression, the arrangement of the mask M2 for the display panel to be manufactured on the cylindrical wheel 21, the required interval Sx, and the like can be set so as to satisfy 1.3≤L/φ≤3.8.

In addition, the mask surface P1 can be configured to have a ratio L/φ of less than 3.8 by arranging three masks M1 and M2 of the mask pattern for the display panel device as shown in the previous FIG8, or four masks as shown in FIG9. In this case, the value of the ratio L/φ can be obtained based on the relationship when n masks M1 and M2 are arranged in the θ direction with the Y direction as the long side. The vertical and horizontal dimensions of the masks M1 and M2 will also change depending on the width of the peripheral circuit area TAB around the display screen area DPA. Therefore, the magnification of the long side dimension of the masks M1 and M2 enlarged by the peripheral circuit area TAB on both sides (or one side) of the long side direction of the display screen area DPA is set to e1, and the magnification of the short side dimension of the masks M1 and M2 enlarged by the peripheral circuit area TAB on both sides (or one side) of the short side direction of the display screen area DPA is set to e2.

Therefore, when the mask surface P1 is configured in such a way that the Y-direction dimension La is consistent with the long-side dimension of the masks M1 and M2, the Y-direction length L of the mask area on the mask surface P1 is L=La=e1·Ld. Similarly, the θ-direction length πφ(Lb) of the mask area on the mask surface P1 is πφ=n(e2·Lc+Sx), and the ratio L/φ is expressed by the following relationship.

L/φ＝e1·π·Asp·Lc/n(e2·Lc+Sx)

In this relational expression, in the case of the mask M2 shown in FIG. 11 , n=2, e1=1.2, and e2=1.0.

For example, when the aspect ratio of the display screen area DPA of the mask M2 used for the display panel device is set to 16:9 (Asp=1.778), if the mask M2 is arranged in a three-sided manner in the θ direction (n=3), when the interval Sx is zero, the ratio L/φ is L/φ=e1·π·Asp/n·e2, even if the magnification e1 is set to 1.2 and the magnification e2 is set to 1.0, the ratio L/φ is 2.23.

Furthermore, as shown in the previous Figure 10, if the aspect ratio of the mask area of the entire four sides of the mask M2 (24 inches) arranged in two rows and two columns is approximately the same as the aspect ratio of the mask M (50 inches) arranged on one side with the long side direction of the display screen area DPA facing the θ direction, then the cylindrical wheel 21 can be set to the same size only by the difference in the size of the terminal portion of the peripheral circuit area TAB or the difference in the spacing Sx.

As described above, if the aspect ratio of the display screen area DPA of the display panel is 16:9 or 2:1, when it is close to 2:1, in order to effectively arrange the masks M, M1, and M2 for the display panel on the outer peripheral surface of the cylindrical wheel 21, it is preferred that the relationship between the length L of the cylindrical wheel (cylindrical mask) 21 in the direction (Y direction) orthogonal to the scanning exposure direction (θ direction) and the diameter φ satisfies 1.3≤L/φ≤3.8. Furthermore, if the aspect ratio of a single mask M, M1, and M2 is close to 2:1, when arranging a plurality of these masks in a multi-faceted configuration, it is preferred that the overall aspect ratio (L:Lb) of the mask area on the mask surface P1 occupied by the multi-faceted configuration is close to 1:1. In addition, the interval Sx (or the margin 92) is preferably set to be fixed.

In addition, the relationship between the diameter φ of the outer peripheral surface (mask surface P1) of the cylindrical wheel 21 and the total length L (La) in the direction of the first axis AX1 of the mask pattern formed on the mask surface P1 preferably satisfies 1.3≤L/φ≤3.8, but further, if it is set to 1.3≤L/φ≤2.6, the above-mentioned effect can be better obtained. For example, if the mask M2 shown in Figure 11 is rotated 90° and two are arranged without spacing in the Y direction as two surfaces, so that the long side direction becomes the θ direction, then L/φ≒2.6. In this case, the length πφ (Lb) of one mask M2 in the θ direction is πφ＝e1·Ld, and the total length L of the two masks M2 arranged in the Y direction is L＝2·e2·Lc. Therefore, since Asp=Ld/Lc, the ratio L/φ becomes L/φ=2π·e2/e1·Asp. If it is assumed that e1=1.2, e2=1.0, and Asp=2/1, then L/φ=π/1.2≒2.6.

In addition, the exposure device U3 is preferably capable of making the mask M (M1, M2) replaceable. By making the mask replaceable, the mask pattern for display panels of various sizes or electronic circuit substrates can be projected and exposed onto the substrate P. In addition, even if there are many types of faces of the mask (M, M1, M2, etc.) formed on the mask surface P1 of the cylindrical wheel 21, there is no need to make the gap (interval Sx) generated between the masks too large. That is, it is possible to suppress the reduction in the proportion of the effective mask area (mask utilization rate) occupied by the mask surface P1 in the overall area.

In addition, it is preferable to make the mask M (M1, M2) replaceable in such a manner that the diameter φ of the mask surface P1 of the cylindrical wheel 21 and the length L of the mask area in the direction (Y direction) perpendicular to the scanning exposure direction are substantially the same. Thus, by simply replacing the mask M (M1, M2), it is not necessary to adjust other parts such as the projection optical system PL and the illumination optical system IL on the exposure device U3 side, or the distance between the substrate P and the mask surface P1, or only a very small amount of adjustment is required, and the patterns of various devices can be transferred with the same image quality after the mask is replaced.

In addition, in the above-mentioned embodiment, there is a case where the diameter φ of the cylindrical wheel 21 is fixed and masks (M1, M2) for devices with various numbers of faces or different arrangement directions are arranged on the mask surface P1, or the diameter φ of the cylindrical wheel 21 is different and devices with various numbers of faces are arranged on the mask surface P1. However, in either case, a plurality of mask patterns can be arranged on the mask surface P1 with a small gap by making the shape of the cylindrical mask surface P1 satisfy the relationship of 1.3≤L/φ≤3.8. Thus, the pattern of the device (display panel) can be efficiently transferred to the substrate P. In addition, by setting the cylindrical mask of the cylindrical wheel 21 to a shape that satisfies the relationship of 1.3≤L/φ≤3.8, patterns of devices of various sizes can be efficiently arranged while reducing the gaps between the patterns of multiple devices, and the change in the diameter φ of the cylindrical mask can be reduced.

In addition, as shown in Figures 8 to 11, the number of mounting surfaces of the photomasks M1 and M2 can be set to two, three, four or more surfaces according to the size of the display panel (device) to be manufactured. If the number of mounting surfaces of the photomasks M1 and M2 is increased to three or four, the size of the gap (interval Sx) can be further reduced.

In addition, the cylindrical wheel 21 can optimize (increase) the width of the illumination area IR or the projection area PA in the scanning exposure direction (θ direction) relative to the drum diameter (diameter φ) by satisfying 1.3≤L/φ≤3.8. The relationship between the diameter φ of the photomask surface P1 of the cylindrical wheel 21 and the exposure slit width in the scanning exposure direction is described below using FIG. 12.

FIG12 is a graph showing the relationship between the diameter φ of the cylindrical wheel 21 (mask surface P1) and the exposure slit width D by changing the defocus amount. In FIG12 , the vertical axis represents the exposure slit width D [mm], which represents the width in the θ direction (X direction) of the projection area PA (FIG. 3) formed on the substrate P. The vertical axis represents the diameter φ [mm] of the cylindrical wheel 21 (mask surface P1). In addition, the so-called defocus amount is determined by the number of apertures NA on the image side (substrate P side) of the projection optical system PL of the exposure device U3, the wavelength λ of the illumination light for exposure, and the depth of focus DOF defined by the process constant k (k≤1). Here, the deviation amount (defocus amount) in the focusing direction between the optimal focal plane of the projection image and the surface of the substrate P is simulated for two cases of 25 μm and 50 μm.

Here, in the simulation of FIG12 , the numerical aperture NA of the projection optical system PL is set to 0.0875, the wavelength λ of the illumination light is set to 365 nm of the i-line of the mercury lamp, and the process constant k is set to about 0.5, so the focal depth DOF is obtained according to DOF=k·λ/NA ² , and the width is about 50 μm (about -25 μm to +25 μm). In addition, as a resolution under this condition, 2.5 μm L/S can be obtained. The 25 μm defocus represented by the dotted line in FIG12 refers to a state in which a focus deviation of about 1/2 of the focal depth DOF is generated within the exposure slit width D; the 50 μm defocus represented by the solid line refers to a state in which a focus deviation equivalent to the degree of the focal depth DOF is generated within the exposure slit width D. That is, the graph at 25 μm defocus represented by the dotted line shows the relationship between the diameter φ and the exposure slit width D when 1/2 of the width of the depth of focus DOF (width 25 μm) is allowed as the error caused by the bending of the mask surface P1 of the cylindrical wheel 21; the graph at 50 μm defocus represented by the solid line shows the relationship between the diameter φ and the exposure slit width D when the error caused by the bending of the mask surface P1 of the cylindrical wheel 21 is allowed up to the width of the depth of focus DOF.

In FIG. 12 , the exposure slit width D when the allowable defocus amount (referred to as ΔZ) is 25 μm and the exposure slit width D when the defocus amount is 50 μm are obtained by the following calculation when the diameter φ of the cylindrical wheel 21 is changed within the range of 100 mm to 1000 mm.

D＝2·[(φ/2) ² -(φ/2-ΔZ) ² ] ^0.5

According to the simulation, for example, when the diameter φ is 500 mm, the maximum exposure slit width D when the defocus amount ΔZ is allowed to be up to 25 μm is about 7.1 mm, and the maximum exposure slit width D when the defocus amount ΔZ is allowed to be up to 50 μm is about 10.0 mm.

As shown in FIG. 12 , the larger the diameter φ of the cylindrical wheel 21, the larger the exposure slit width D that satisfies the allowable defocus amount. In the case of a mask M2 as shown in FIG. 11 , in which the aspect ratio of the display screen area DPA is 2:1 and the peripheral circuit area TAB is provided only in the length direction of the display screen area DPA, if the margin 92 (interval Sx) is not provided and only one side of the mask M2 is formed on the entire mask surface P1 of the cylindrical wheel 21, the ratio L/φ will change greatly by setting the length direction of the mask M2 to the circumferential direction (θ direction) of the cylindrical wheel 21 or the direction (Y direction) of the first axis AX1. If the length direction of the mask M2 is set to the Y direction as shown in FIG. 11 , the length Lc (short side) of one side of the mask M2 in the θ direction is equal to the entire circumferential length πφ of the outer peripheral surface of the cylindrical wheel 21, so that φ=Lc/π. At this time, the length L of the mask M2 on the cylindrical wheel 21 in the direction of the first axis AX1 (Y direction) is L=1.2·Ld, as in the case of FIG. 11. Since the aspect ratio is 2:1 and Ld=2Lc, the ratio L/φ in this case is L/φ=2.4·π≒7.5. On the other hand, if the short side direction of the mask M2 is set to the Y direction, the entire circumferential length πφ of one side of the mask M2 in the θ direction is 1.2·Ld, and the Y-direction length L of the mask M2 on the cylindrical wheel 21 is Lc. Therefore, the ratio L/φ in this case is L/φ=π/2.4≒1.3.

If the Y-direction length L of the photomask is set within the range of the total Y-direction dimensions of the projection areas PA1 to PA6 (FIG. 3) of the projection optical system PL of the exposure device U3, and the length L is fixed, the ratio changes from 1.3 to 7.5 by about six times, which means that the diameter φ of the cylindrical wheel 21 changes by about six times. The change of the diameter φ by about six times in FIG. 12 corresponds to, for example, a change in the diameter φ from 150 mm to 900 mm. In this case, when the allowable defocus amount ΔZ is set to 25 μm, the exposure slit width D changes from about 3.9 mm at φ150 mm to about 9.5 mm at φ900 mm. Therefore, when the Y-direction length L of the photomask is set to be fixed, the exposure slit width D is reduced to about 40% when the cylindrical photomask with a diameter of φ900 mm is changed to the cylindrical photomask with a diameter of φ150 mm. The same is true when the allowable defocus amount ΔZ is set to 50 μm.

Therefore, when the ratio L/φ is in the range of 1.3 to 7.5, when the exposure is performed with the contrast of the projection image fixed, the exposure amount given to the substrate P is simply reduced to 40%. In order to make the exposure amount given to the substrate P reach an appropriate value (100%), the substrate P is moved at a speed of about 40% relative to the moving speed of the substrate P when the projection area PA is exposed based on the exposure slit width D set to 9.5 mm. That is, since the conveying speed of the substrate P itself needs to be reduced to about 40%, the productivity (throughput) will be reduced to less than half. When the projection area PA is exposed using the exposure slit width D set to 3.9 mm, in order to avoid reducing the conveying speed of the substrate P, it is also possible to consider increasing the brightness of the projection image in the projection area PA, that is, the illuminance of the illumination light beam ELI. In this case, the illuminance of the illumination light beam EL1 irradiating the mask surface P1 needs to be increased to about 2.5 times relative to the illuminance when the exposure slit width D is 9.5 mm.

In contrast, when the configuration of the mask M2 shown in FIG. 11 is adopted on both sides, the ratio L/φ can be reduced to a range below about 3.8 (1.2·π) (1.3 to 3.8). When the Y-direction length L of the mask is fixed, the diameter φ of the cylindrical mask (cylindrical wheel 21) varies within a range of about three times, for example, only φ=900mm to 300mm needs to be considered. According to the simulation of FIG. 12, when the diameter φ is 300mm and the allowable defocus amount ΔZ is set to 25μm, the exposure slit width D is approximately 5.5mm. Therefore, relative to the case where the exposure slit width D is approximately 9.5mm, the conveying speed of the substrate P is only reduced to about 60%. In this way, by limiting the aspect ratio of the mask area formed on the mask surface P1 of the cylindrical wheel 21 in a manner such that the ratio L/φ is about 1.3 to about 3.8, the change in the exposure slit width D can be suppressed.

Similarly, when three photomasks M2 of FIG. 11 are arranged without spacing Sx in the θ direction as shown in FIG. 8 , L/φ＝0.4π·Asp, and the diameter φ of the cylindrical wheel 21 may vary within a range of about 1.8 times, for example, from 500 mm to 900 mm. The exposure slit width D with a defocus amount of 25 μm is reduced from about 9.5 mm when the diameter φ is 900 mm to about 7.1 mm, but this is equivalent to a reduction in productivity of about 75%. However, this is an improvement over the case in which the productivity in the previous example is reduced to less than half. Further, when four photomasks M2 of FIG. 11 are arranged without spacing Sx in the θ direction as shown in FIG. 9 , L/φ＝0.3π·Asp, and the diameter φ of the cylindrical wheel 21 may vary within a range of about 1.3 times, for example, from 700 mm to 900 mm. The exposure slit width D with a defocus amount of 25 μm is reduced from about 9.5 mm when the diameter φ is 900 mm to about 8.4 mm. This is equivalent to a reduction in productivity of about 88%, but it is a significant improvement compared to the situation in which productivity dropped to less than half in the previous example, and exposure can be performed with essentially no loss. In addition, if the exposure slit width D is reduced by about 75% or 88%, the illumination intensity of the illumination beam EL1 can be easily increased by increasing the light intensity of the light source 31, or increasing the number of light sources, etc., without causing any reduction in productivity. In addition, it can be seen that the size of the mask area becomes fixed as it approaches a certain value. That is, according to the screen size (diagonal length Le) of the display screen area DPA, the configuration of the mask M on one side, the configuration of the mask M1 or the configuration of the mask M2 on multiple sides are respectively adopted, so that the size of the mask area (L×πφ) can be achieved as a cylindrical wheel 21 (diameter φ remains unchanged), and the productivity can be fixedly maintained.

However, although the range of the ratio L/φ is set to about 1.3 to about 3.8, this is because it is assumed that the longitudinal dimension of the mask M2 for the display panel with an aspect ratio of 2:1 includes the width of the peripheral circuit area TAB and is increased by 20% (1.2 times) relative to the longitudinal dimension Ld of the display screen area DPA as shown in FIG. 11. Therefore, if the longitudinal dimension of the mask is enlarged to e1 times the longitudinal dimension Ld of the display screen area DPA, the ratio L/φ is expressed by the following range because Asp=Ld/Lc.

π/(e1·Asp)≤L/φ≤e1·π

By using a cylindrical wheel 21 (cylindrical mask) that meets this condition, the exposure device U3 of this embodiment can suppress the projection image distortion (distortion) caused by the projection error caused by the cylindrical surface, or the change of the projection image surface (focus deviation) caused by the arc, while arranging and transferring multiple mask patterns for the display panel (device) to the substrate P with reduced gaps.

As mentioned above, the configuration examples of the masks M, M1, M2, etc. formed on the cylindrical mask (cylindrical wheel 21) in this embodiment are summarized as shown in Figures 13 and 14. Figure 13, like Figure 7, shows the configuration of one side of the mask M with the θ direction as the length direction, and Figure 14, like Figure 11, shows the configuration of two sides of the mask M2 with the Y direction as the length direction arranged in the θ direction. Figure 13, like Figure 7, shows the configuration of the mask M for the display panel with the diagonal length Le (inch) of the display screen area DPA in a manner such that the long side is oriented in the θ direction. In this case, if the ratio of the long side dimension Ld to the short side dimension Lc of the display screen area DPA (Ld/Lc) is taken as the aspect ratio Asp, and the mask M including the peripheral circuit area TAB around the display screen area DPA is formed on the outer peripheral surface (mask surface P1) of the cylindrical wheel 21 without any margin, the length πφ of the mask M in the θ direction is πφ＝e1·Ld＝e1·Asp·Lc, and the length L in the Y direction is L＝e2·Lc. As described above, e1 is the magnification factor indicating how much the length direction of the mask M is enlarged relative to the length direction of the display screen area DPA by the total width of the peripheral circuit area TAB attached on both sides or one side of the length direction of the display screen area DPA. Similarly, e2 is the magnification factor indicating how much the short side direction of the mask M is enlarged relative to the short side direction of the display screen area DPA by the total width of the peripheral circuit area TAB attached on both sides or one side of the short side direction of the display screen area DPA (Ta in FIG. 13). According to the above description, the minimum required size of the outer peripheral surface (mask surface P1) of the cylindrical wheel 21 is πφ×L. At this time, the ratio L/φ of the length L and the diameter φ of the mask M is expressed as follows.

L/φ＝π·e2/e1·Asp

Assuming that the aspect ratio (πφ:L) of the mask M is further increased, if the width Ta of the peripheral circuit area TAB adjacent to the long side of the display screen area DPA is set to zero (e2=1) and the magnification e1 is set to 1.2 (increase by 20%), the ratio L/φ becomes π/1.2·Asp. Therefore, when the aspect ratio Asp is 2 (2/1), the ratio L/φ is π/2.4≒1.3; when the aspect ratio Asp is 1.778 (16/9), the ratio L/φ is π/2.134≒1.47.

FIG. 14 is the same as FIG. 11 , in which two masks M2 are arranged along the θ direction on both sides with the long side direction of the display screen area DPA being the Y direction, and the definitions of the aspect ratio Asp and the magnifications e1 and e2 are the same as those in FIG. 13 . The size of a mask M2 including the peripheral circuit area TAB around the display screen area DPA is L×Lg, and the two masks M2 are arranged in parallel with a spacing Sx in the θ direction. Therefore, when the mask including the two masks M2 and the two spacings Sx is formed on the outer peripheral surface (mask surface P1) of the cylindrical wheel 21 without any blank space, the length πφ of the mask in the θ direction is πφ=2(Lg+Sx), and the length L in the Y direction is L=e1·Ld. Therefore, the ratio L/φ at this time is expressed as follows.

L/φ＝π·e1·Ld/2(Lg+Sx)

Here, assuming that the magnification e1 is 1.2 (increase of 20%), the width Ta of the peripheral circuit area TAB adjacent to the long side of the display screen area DPA is zero (e2=1), and the interval Sx is zero, according to the relationship of Lg=e2·Lc, Ld=Asp·Lc, the ratio L/φ is 0.6π·Asp. Therefore, when the aspect ratio Asp is 2 (2/1), the ratio L/φ is approximately 3.8; when the aspect ratio Asp is 1.778 (16/9), the ratio L/φ is approximately 3.4.

In this way, if the size (inches) of the display panel (device) arranged on the cylindrical mask surface P1, the aspect ratio Asp of the display screen area DPA, and the width of the peripheral circuit area TAB are determined, based on this, a better cylindrical mask (cylindrical wheel 21) with a ratio L/φ suitable for the device specifications of the exposure device U3 can be simply produced.

Furthermore, a specific example is described using Figures 15 to 18. First, as shown in Figure 7 or Figure 13 above, a case where a mask M with the long side direction of the display screen area DPA set to the θ direction is arranged on one side on the mask surface P1 of the cylindrical wheel 21 is used as a comparison reference. Here, in the specific example, the projection optical system PL of the exposure device U3 projects the mask pattern onto the substrate P at the same magnification. Therefore, a mask pattern of the actual size of the display panel is formed on the mask surface P1 of the cylindrical wheel 21. In addition, the display screen area DPA of the display panel is set to a high-quality size (aspect ratio of 16:9) and a 60-inch screen. In this case, the short side dimension Lc of the display screen area DPA is 74.7 cm, the long side dimension Ld is 132.8 cm, and the diagonal length Le is 152.4 cm. In addition, regarding the overall size of the mask M including the peripheral circuit area TAB, the magnification e1 related to the long side direction of the display screen area DPA is set to 1.2 (increase of 20%), the magnification e2 related to the short side direction is set to 1.15 (increase of 15%), the long side direction (θ direction) is set to e1·Ld=159.4cm, and the short side direction (Y direction) is set to e2·Lc=85.9cm. Furthermore, the length of the blank portion 92 in the θ direction shown in Figure 6 or Figure 7 is set to 5.0cm. Since the mask M is set on the mask surface P1 of the cylindrical wheel 21 under the above conditions, the θ direction dimension πφ of the mask surface P1 becomes 164.4cm. Therefore, the diameter φ of the cylindrical wheel 21 needs to be greater than 52.33cm, for example, set to 52.5cm. In addition, although the overall Y-direction length of the mask M under the above conditions is set to 85.9 cm, since the mask M is used as a reference, the Y-direction full width of the exposure area connected along the Y-direction by the projection areas PA1 to PA6 of the projection optical systems PL1 to PL6 of the exposure device U3 is slightly larger than 85.9 cm and is 87 cm. Here, according to the simulation results shown in FIG. 12 , if the diameter φ of the cylindrical wheel 21 (cylindrical mask M) is set to 52.5 cm, the exposure slit width D when the allowable defocus amount is set to 25 μm is 7.4 mm, and the exposure slit width D when the allowable defocus amount is set to 50 μm is 10.3 mm. Therefore, when performing scanning exposure of the substrate P using the mask M (cylindrical wheel 21) as a reference shown in FIG. 13 , various exposure conditions (the moving speed of the substrate P, the illumination of the illumination beam EL1, etc.) are optimized based on the exposure slit width D of 7.4 mm or less, or 10.3 mm or less. That is, when the allowable defocus amount ΔZ is to be set to less than 25 μm, the opening of the illumination field aperture 55 in Figure 4 or the opening of the projection field aperture 63 in the projection optical system PL is adjusted so that the exposure slit width D (the width of the projection area PA in the scanning exposure direction) becomes a specified value less than 7.4 mm.

Next, the case where a 32-inch display panel mask M3 having an aspect ratio of 16:9 (Asp=16/9) is arranged on the outer peripheral surface (mask surface P1) of the cylindrical wheel 21 set for the mask M for the 60-inch display panel shown in FIG. 13 is described. The dimensions of the mask surface P1 of the cylindrical wheel 21 are a length L=85.9 cm in the Y direction and a length πφ=164.4 cm in the θ direction. However, similarly to the reference mask M, when a 32-inch display panel mask M3 is arranged (arranged on one side) in such a manner that the length direction of the display screen area DPA is in the θ direction, a wide blank area is generated around the mask M3 on the mask surface P1.

In the case of the 32-inch display panel, the long side dimension Ld of the display screen area DPA is 70.8 cm, and the short side dimension Lc is 39.9 cm. In addition, when the magnification e1 of the peripheral circuit area TAB adjacent to the display screen area DPA on both sides or one side in the longitudinal direction is set to about 1.2 (increase of 20%), the dimension of the mask M3 in the θ direction is enlarged by about 15 cm to become 85.8 cm. If a margin 92 of about 5 cm is further provided along the θ direction, the total length becomes 90.8 cm. Therefore, the mask M3 is formed on the mask surface P1 of the cylindrical wheel 21 prepared for the reference mask M as only about 55% of the entire circumferential length (πφ=164.4 cm). In addition, the Y-direction length L of the mask surface P1 of the reference cylindrical wheel 21 is 85.9 cm. In contrast, if the magnification e2 in the short side direction of the display screen area DPA is set to about 1.15 (increase of 15%), the Y-direction length of the mask M3 becomes 45.8 cm. Therefore, the mask M3 is formed to be only about 53% of the Y-direction dimension (L=85.9 cm) on the mask surface P1 of the reference cylindrical wheel 21. Therefore, when a mask M3 for a 32-inch display panel is arranged on the mask surface P1 of the reference cylindrical wheel 21 in such a manner that the length direction of the display screen area DPA is the θ direction, the area occupied by the mask M3 is only about 30% of the entire area of the mask surface P1, so the efficiency is not good.

Therefore, in order to efficiently arrange a mask M3 on the cylindrical wheel 21, if the diameter φ of the cylindrical wheel 21 is changed so that the total length of 90.8 cm, which is the sum of the dimension of the mask M3 in the θ direction and the dimension of the margin 92, becomes the entire circumferential length, the minimum diameter φ only needs to be 28.91 cm. Therefore, if a cylindrical wheel with a diameter φ of 29 cm is prepared as the cylindrical wheel 21 for the mask M3, then according to the simulation results of FIG. 12, the exposure slit width D when the diameter φ = 29 cm is about 5.4 mm when the allowable defocus amount ΔZ is 25 μm, and is about 7.6 mm when the allowable defocus amount ΔZ is 50 μm.

This is compared with the exposure slit width D (7.4 mm or 10.3 mm) set relative to the reference cylindrical wheel 21. In the case of the reference mask surface P1 (cylindrical wheel 21 with a diameter of φ=52.5 cm), the exposure slit width D is set to 10.3 mm (allowable defocus amount 50 μm), and the moving speed of the substrate P set in a manner that can obtain an appropriate exposure amount is set to V1. At this time, when the pattern of the mask M3 configured on one side for a 32-inch display panel formed on the cylindrical wheel 21 with a diameter of φ=29 cm is exposed on the substrate P under the same conditions, since the exposure slit width D is 7.6 mm (allowable defocus amount 50 μm), when the illumination is fixed, the moving speed V2 of the substrate P to obtain an appropriate exposure amount becomes V2=(7.6/10.3)V1, and the substrate processing speed of the production line as a whole is reduced by approximately 25%. When the allowable defocus amount ΔZ is 25 μm, the productivity is also reduced to the same extent.

Therefore, FIG. 15 is used to illustrate a specific example in which the mask M3 for a 32-inch display panel with an aspect ratio of 16:9 is set as a cylindrical mask (cylindrical wheel 21) configured on both sides in the configuration shown in the previous FIG. 14. In FIG. 15, the long side dimension Ld of the display screen area DPA is 70.8 cm, and the short side dimension Le is 39.9 cm. In addition, since the magnification e1 of the length direction (Y direction) of the mask M3 caused by the peripheral circuit area TAB is set to about 1.2, and the magnification e2 of the short side direction (θ direction) is set to about 1.15, the Y-direction length L of the mask M3 increases by about 15 cm to 85.8 cm; the θ-direction length Lg of the mask M3 increases by about 6 cm to 45.9 cm.

Here, when the dimension in the θ direction of the interval Sx (blank portion 92) adjacent to the long side of the mask M3 is set to 10 cm, the length in the θ direction of the entire mask area including the two masks M3 and the two intervals Sx becomes 110.8 cm due to 2(Lg+Sx). Therefore, the diameter φ of the cylindrical wheel 21 in this case only needs to be about 35.3 cm. In addition, the Y-direction length L of the mask surface P1 on the cylindrical wheel 21 is at least 85.8 cm. This length L (85.8 cm) falls exactly within the range of 87 cm of the full Y-direction width of the exposure area set by the cylindrical wheel 21 as a reference (the total Y-direction length of the projection areas PA1 to PA6). Therefore, the cylindrical mask (cylindrical wheel 21 with φ=35.3 cm, L=85.8 cm) with two sides of the mask M3 shown in Figure 15 can be installed on the exposure device U3 in the same way as the cylindrical mask (cylindrical wheel 21 with φ=52.5 cm, L=85.9 cm) serving as a reference, and the pattern of the mask M3 can be efficiently exposed to the substrate P.

FIG16 is an expanded view showing the schematic structure of another example in which the mask M3 for the 32-inch display panel shown in FIG15 is configured on both sides. Here, it is assumed that two masks M3 of the same size as FIG15 are arranged without gap in the Y direction in such a way that the length direction of the display screen area DPA is the θ direction, and the Y-direction dimension L of the two masks M3 is 91.8 cm (2×45.9 cm). This length L (91.8 cm) does not fall within the range of 87 cm of the full Y-direction width (the total Y-direction length of the projection areas PA1 to PA6) of the exposure area set by the cylindrical wheel 21 serving as a reference. That is, the two sides of the configuration after rotating the same mask M3 as FIG15 by 90° cannot be configured on the mask surface P1 of the cylindrical wheel 21 serving as a reference.

FIG. 17 is a schematic diagram showing the structure of another example in which the mask M3 for the 32-inch display panel shown in FIG. 15 is configured on one side. Here, it is assumed that a mask M3 of the same size as that in FIG. 15 is configured in such a way that the short side direction of the display screen area DPA is in the θ direction, and the interval Sx of the margin 92 in the θ direction is set to 10 cm. This configuration of the mask M3 is extremely small relative to the occupied area of the mask surface P1 of the standard cylindrical wheel 21, and is inefficient. Therefore, if a cylindrical wheel 21 with a size adapted to the mask M3 configured on one side of FIG. 17 is assumed, the total circumferential length πφ of the cylindrical wheel 21 is πφ=55.9 cm by the sum of the θ direction dimension Lg (45.9 cm) of the mask M3 and the dimension (10 cm) of the margin 92 (Sx). Since the diameter φ of the cylindrical wheel 21 is greater than 17.8 cm, it can be regarded as 18 cm. In addition, since the Y-direction length L of the mask M3 in this case is 85.8 cm similarly to FIG. 15 , the ratio L/φ is approximately 4.77.

Thus, if the diameter φ (18 cm) is set smaller than the diameter (52.5 cm) of the standard cylindrical mask (cylindrical wheel 21), the mask M3 can be efficiently arranged on the mask surface P1, but the productivity (throughput) will be reduced. According to the simulation of FIG. 12, if the diameter of the mask surface P1 is set to 18.0 cm, the exposure slit width D is about 4.3 mm when the allowable defocus amount ΔZ is set to 25 μm, and the exposure slit width D is about 6.0 mm when the allowable defocus amount ΔZ is set to 50 μm. Therefore, the moving speed V2 of the substrate P is reduced relative to the moving speed V1 of the substrate P when the standard cylindrical mask (cylindrical wheel 21) is used, as the exposure slit width D becomes narrower. When the allowable defocus amount ΔZ is set to 25 μm, V2 = (4.3/7.4) V1, and when the allowable defocus amount ΔZ is set to 50 μm, V2 = (6.0/10.3) V1. In either case, productivity is reduced to approximately 58% compared to the case of using a standard cylindrical mask.

Next, a specific example in which three masks M3 having the same size as that of FIG. 15 are arranged in the θ direction with the longitudinal direction facing the Y direction as shown in FIG. 18 is similar to FIG. 8 in that the mask M3 is arranged on three surfaces.

Here, if the θ-direction dimension of the blank portion 92 (Sx) or the interval Sx adjacent to each long side of the three masks M3 is set to 9 cm, then since the short side dimension Lg of the mask M3 is 45.9 cm, the θ-direction length of the mask area as a whole is 164.7 cm due to 3 (Lg + Sx). In this case, if the θ-direction length of the mask area as a whole is made consistent with the entire circumferential length πφ of the cylindrical wheel 21, the diameter φ of the cylindrical wheel 21 is greater than 52.43 cm. This value is approximately the same as the diameter φ = 52.5 cm of a standard cylindrical mask. In addition, the Y-direction dimension L of the mask area is 85.8 cm, which falls within the Y-direction total width of 87 cm of the exposure area (projection areas PA1 to PA6).

Thus, if the mask M3 is used for a 32-inch display panel with an aspect ratio of 16:9, the mask M3 can be effectively configured by configuring the three surfaces as shown in FIG. 18, only the size of the margin 92 and the interval Sx need to be adjusted on the mask surface P1 of the standard cylindrical wheel 21 (φ=52.5 cm). Therefore, when the mask M3 is configured on three surfaces as shown in FIG. 18, the productivity will not be reduced because the size (φ×L) of the standard cylindrical mask can still be used. In addition, in the case of FIG. 18, the ratio L/φ is approximately 1.63, which falls within the range of 1.3≤L/φ≤3.8 that is considered to be effectively producible.

As shown in Figures 15 to 18, the size of the mask surface P1 of the cylindrical mask (cylindrical wheel 21) that can be mounted on the exposure device U3 is used as a reference. When a display panel device of any size is manufactured, the directionality and the number of surfaces are adjusted in a manner such that the ratio L/φ when the mask is arranged on one side or on multiple sides on the cylindrical wheel 21 is set to a range of 1.3 to 3.8, thereby effectively transferring the pattern without reducing production efficiency.

In addition, Figures 15 to 18 are based on the size of the mask surface P1 of the display panel device for making the display screen area DPA as a 60-inch side with an aspect ratio of 16:9. However, it is not limited to this. For example, the display screen area DPA can also be set to a 65-inch screen with a high-quality size of an aspect ratio of 16:9. In this case, the diagonal length Le of the display screen area DPA configured as shown in Figure 13 is 165.1cm, the short side Lc extending along the Y direction is 80.9cm, and the long side Ld extending along the θ direction is 143.9cm. In addition, the overall size of the mask M including the peripheral circuit area TAB is larger than the size of the display screen area DPA, and the magnification e1=1.2 is increased only along the long side direction (θ direction) (the length direction of the display screen area DPA increases by 20%), and the magnification e2=1.15 is increased along the short side direction (Y direction) (the short side direction of the display screen area DPA increases by 15%). Therefore, in the case of a mask M configured on one side for a 65-inch display panel with an aspect ratio of 16:9, the dimension of the mask M in the longitudinal direction is 172.7 cm due to e1·Asp·Lc as shown in FIG. 13, and the dimension in the short side direction is 93.1 cm due to e2·Lc as shown in FIG. 13. In the case of a mask M configured on one side, a margin portion 92 is provided adjacently along the θ direction. If its θ direction dimension (Sx) is set to 5 cm, the θ direction dimension of the mask surface P1 becomes approximately 178 cm, and the diameter φ is greater than 56.7 cm. In addition, since the Y direction length of the mask surface P1 is 93.1 cm, on the exposure device U3 that can be mounted with the mask based on the cylindrical mask for 65 inches, six projection optical systems PL that change the Y direction dimension of the projection area PA are provided in such a manner that the total Y direction width of the exposure area (the total Y direction width of the projection areas PA1 to PA6) is, for example, 95.0 cm. Alternatively, seven projection optical systems are provided with one additional projection optical system PL in the Y direction. The ratio L/φ of the cylindrical light mask (cylindrical wheel 21) configured on one side of the 65-inch display panel with an aspect ratio of 16:9 is L/φ=1.64 (≒93.1/56.7). In addition, since the diameter φ of the cylindrical light mask is 56.7 cm, according to the simulation results of FIG. 12 , the exposure slit width D is approximately 7.5 mm when the allowable defocus amount ΔZ is set to 25 μm, and is approximately 10.6 mm when the allowable defocus amount ΔZ is set to 50 μm.

Therefore, referring to FIG19, a specific example of arranging three masks M4 for 37-inch display panels on multiple surfaces in the arrangement shown in FIG18 on a cylindrical mask (φ=56.7 cm, L=93.1 cm) for arranging one surface of a 65-inch display panel with an aspect ratio of 16:9 is described. In FIG19, the long side Ld (Y direction) of the 37-inch display screen area DPA is 81.9 cm, and the short side Lc (θ direction) is 46.1 cm. If the magnification e1 in the long side direction and the magnification e2 in the short side direction are both set to 1.15 (increase of 15%), the long side dimension L (e1·Ld) of the mask M4 is approximately 94.2 cm, and the short side dimension Lg (e2·Le) is approximately 53.0 cm.

Here, if the interval Sx between the mask M4 and the mask M4 is set to about 6.0 cm, the total size of the three masks M4 and the three intervals Sx on the mask surface P1 in the θ direction, that is, the total circumferential length πφ is about 177 cm because πφ＝3Lg+3Sx, and the diameter φ is more than 56.4 cm. In addition, since the Y-direction length L of the mask M4 is 94.2 cm, it falls within the Y-direction full width (95 cm) of the exposure area. In addition, in the case of Figure 19, the seventh projection optical system PL (projection area PA7) is added in the Y direction, so that the Y-direction full width of the exposure area becomes 95 cm. From the above, it can be seen that when the mask for the 37-inch display panel shown in Figure 19 is configured on three sides, a cylindrical mask with the same shape and size as the cylindrical mask (cylindrical wheel 21) used to configure the mask M for the 65-inch display panel on one side can be used. Thus, in the case of the mask M4 shown in FIG19 , the intervals Sx between the three masks M4 can be reduced relative to the total area of the mask surface P1 of the reference cylindrical wheel 21 for efficient configuration, and a cylindrical wheel 21 having the same diameter φ as that of the reference cylindrical mask can be used, thereby suppressing the decrease in productivity caused by the reduction in the exposure slit width D.

In addition, when the size of the display screen area DPA of the display panel device is set to 37 inches and the mask M4 used thereon is arranged on both sides, the same arrangement as in FIG. 15 can also be used. In this case, if the total size of the two masks M4 and the two intervals Sx in the θ direction is set to the entire circumferential length πφ of the cylindrical mask and the interval Sx is set to about 6 cm, the diameter φ of the cylindrical mask (cylindrical wheel 21) when the two-sided mask M4 is efficiently arranged in the circumferential direction is 37.6 cm or more.

In this case, the ratio L/φ is approximately 2.5 (≒94.2/37.6). In addition, in the case of the cylindrical wheel 21 with a diameter of φ=37.6 cm, according to the simulation of Figure 12, the exposure slit width D is approximately 6 mm when the allowable defocus amount ΔZ is 25 μm, and is approximately 8.6 mm when the allowable defocus amount ΔZ is 50 μm. Compared with the reference exposure slit width D (7.5 mm, 10.6 mm) set relative to the reference cylindrical mask with a diameter of φ=56.7 cm, the productivity (moving speed of the substrate P) is approximately 80% regardless of whether the allowable defocus amount ΔZ is set to 25 μm or 50 μm. However, if the illumination of the illumination light beam EL1 can be increased by about 20% compared to when the reference cylindrical mask is used for exposure, there will be no substantial decrease in productivity.

In addition, although the exposure device U3 of this embodiment projects the mask pattern of the cylindrical mask (cylindrical wheel 21) onto the substrate P at the same magnification, it is not limited to this. The exposure device U3 can also adjust the structure of the projection optical system PL, the circumferential speed of the cylindrical mask (cylindrical wheel 21), the moving speed of the substrate P, etc., and enlarge the pattern of the mask M at a specified magnification and project it onto the substrate P, or reduce it at a specified magnification and project it onto the substrate P.

As described above, in the cylindrical light mask that can be installed on the exposure device U3 of the present embodiment, as shown in Figures 8, 9, 14, 15, 18, and 19, in the case of a multi-faceted configuration in which the long side direction of the rectangular display screen area DPA is set to the Y direction and two or more light mask areas (light masks M1, M2, M3, M4) are arranged at intervals Sx along the θ direction, the cylindrical light mask (cylindrical wheel 21) is constructed as follows.

A cylindrical mask having a mask pattern (masks M1 to M4) formed along a cylindrical surface (P1) having a fixed radius (Rm) relative to a center line (AX1), the cylindrical mask being mounted on an exposure device in a manner capable of rotating around the center line, and having n (n≥2) rectangular mask areas (masks M1 to M4) for display panels arranged at intervals Sx along the circumferential direction (θ direction) of the cylindrical surface, the mask area comprising: a display screen area (DPA) having a long side dimension of Ld, a short side dimension of Lc, and an aspect ratio of Asp (=Ld/Lc); and a peripheral circuit area (TAB) adjacent to the periphery of the display screen area, when the mask is placed When the dimension L in the longitudinal direction (Y direction) of the area is set to e1 times (magnification e1≥1) of the long side dimension Ld of the above-mentioned display screen area, and the dimension in the short side direction (θ direction) of the above-mentioned mask area is set to e2 times (magnification e2≥1) of the short side dimension Lc of the above-mentioned display screen area, the length of the above-mentioned cylindrical surface in the center line direction (Y direction) is set to be greater than the above-mentioned dimension L (=e1·Ld), and the diameter of the above-mentioned cylindrical surface is set to φ, and the entire circumferential length πφ of the above-mentioned cylindrical surface is set to n(e2·Lc+Sx), and further, the above-mentioned diameter φ, the above-mentioned number n, and the above-mentioned interval Sx are set in such a way that the ratio of the dimension L to the diameter φ is in the range of 1.3≤L/φ≤3.8.

[Second Embodiment]

Next, the exposure device U3a of the second embodiment is described with reference to FIG20. In addition, in order to avoid repeated description, only the parts different from the first embodiment are described, and the same components as those of the first embodiment are marked with the same figure marks as those of the first embodiment for description. FIG20 is a diagram showing the overall structure of the exposure device (substrate processing device) of the second embodiment. The exposure device U3 of the first embodiment is a structure in which the substrate P passing through the projection area is held by a cylindrical substrate support tube 25, but the exposure device U3a of the second embodiment holds the substrate P in a planar state by a substrate support mechanism 12a that can move one-dimensionally or two-dimensionally in the XY plane. Therefore, the substrate P of this embodiment can be not only a sheet-like thin substrate with a flexible resin (PET or PEN, etc.) as the base, but also a sheet-like thin glass substrate.

In the exposure device U3a of the second embodiment, the substrate support mechanism 12a includes a substrate stage 102 equipped with a support surface P2 for holding the substrate P in a planar state, and a moving device (not shown) for scanning and moving the substrate stage 102 in the X direction within a plane perpendicular to the center plane CL.

Since the supporting surface P2 of the substrate P in Figure 20 is a plane substantially parallel to the XY plane (a plane orthogonal to the center plane CL), the main light ray of the projection light beam EL2 reflected from the light mask M and projected onto the substrate P after passing through the projection optical module PLM (projection optical system PL1~PL6) is set to be perpendicular to the XY plane.

In addition, in the second embodiment, when the projection magnification of the projection optical module PLM is set to equal magnification (×1), similarly to the previous Figure 2, when observed in the XZ plane, the circumferential distance CCM from the center point of the odd-numbered illumination area IR1 (and IR3, IR5) on the mask M to the center point of the even-numbered illumination area IR2 (and IR4, IR6) is set to be substantially equal to the distance CCP in the X direction (scanning exposure direction) from the center point of the odd-numbered projection area PA1 (and PA3, PA5) on the substrate P along the supporting surface P2 to the center point of the even-numbered second projection area PA2 (and PA4, PA6).

In the exposure device U3a of FIG. 20 , the moving device (linear motor for scanning exposure and actuator for micro-motion, etc.) of the substrate support mechanism 12a is also controlled by the lower control device 16 to drive the substrate stage 102 in precise synchronization with the rotation of the cylindrical wheel 21 holding the cylindrical mask M. Therefore, the moving position of the substrate stage 102 in the X direction and the Y direction is precisely measured by a laser interferometer or a linear encoder for distance measurement, and the rotation position of the cylindrical wheel 21 is also precisely measured by a rotary encoder. In addition, the support surface P2 of the substrate stage 102 can also be composed of an adsorption holder that vacuum adsorbs the substrate P or electrostatically adsorbs the substrate P during scanning exposure, or can be composed of a Bernoulli type holder that forms a static pressure gas bearing between the support surface P2 and the substrate P to support the substrate P in a non-contact state or a low-friction state.

In the case of the Bernoulli type holder, since the substrate P can be a flexible long thin sheet substrate (web), the substrate P can be moved in the X direction while applying tension in the X direction (and the Y direction) to the substrate P, so there is no need to move the substrate stage 102 (Bernoulli type holder) in the X and Y directions. In addition, the support surface P2 only needs to have an area that can cover the range of the projection areas PA1 to PA6, and the substrate stage 102 can be miniaturized. In addition, in the case of the Bernoulli type holder, if the substrate P is a long thin sheet substrate, since the substrate P can be continuously moved in the long direction while being scanned and exposed, it is more suitable for roll-to-roll manufacturing than the case of an adsorption holder that requires additional time for adsorption/release of the substrate P.

As shown in the exposure device U3a, when the supporting surface P2 is set to a plane substantially parallel to the XY plane and the substrate P is supported in a flat shape, by making the shape condition (L/φ) of the cylindrical wheel 21 that holds the photomask M (M1~M4) in a cylindrical shape satisfy the relationship described in the previous first embodiment, the photomask patterns of display panels of various sizes can be efficiently arranged on the substrate P for exposure and the reduction in productivity can be suppressed.

[Third Embodiment]

Next, the exposure device U3b of the third embodiment is described with reference to FIG. 21. In addition, in order to avoid repeated description, only the parts different from the first and second embodiments are described, and the same components as the first and second embodiments are marked with the same figure marks as the first and second embodiments for description. FIG. 21 is a diagram showing the overall structure of the exposure device (substrate processing device) of the third embodiment. The exposure device U3b of the second embodiment is a structure that uses a reflective mask in which the light reflected by the mask becomes the projection beam EL2, but the exposure device U3b of the third embodiment is a structure that uses a transmissive mask in which the light transmitted through the mask becomes the projection beam EL2.

In the exposure device U3b of the third embodiment, the mask holding mechanism 11a includes: a cylindrical wheel (mask holding cylinder) 21a that holds the mask MA in a cylindrical shape; a guide roller 93 that supports the mask holding cylinder 21a; a driving roller 98 that drives the mask holding cylinder 21a; and a driving unit 99.

The mask holding tube 21a forms a mask surface (P1) for configuring the illumination area IR on the mask MA. In the present embodiment, the mask surface is set to a cylindrical surface having a radius Rm (diameter φ=2Rm) relative to the center line AX1' extending in the Y direction. The cylindrical surface is, for example, the outer peripheral surface of a cylinder, the outer peripheral surface of a cylinder, etc. The mask holding tube 21a is a circular transparent tube with a fixed thickness, which is made of, for example, glass or quartz, and its outer peripheral surface (cylindrical surface) forms the mask surface.

The photomask MA is, for example, a transmissive planar sheet photomask with a pattern formed by a light-shielding layer such as chromium on one surface of a long and extremely thin glass plate (for example, with a thickness of 100 to 500 μm) with good flatness, and is bent along the outer peripheral surface of the photomask holding tube 21a and used in a state of being wound (bonded) to the outer peripheral surface. The photomask MA has a non-pattern forming area where no pattern is formed, and is installed on the photomask holding tube 21a in the non-pattern forming area (equivalent to the peripheral margin 92, etc.). Therefore, in this case, the photomask MA can be installed and removed relative to the photomask holding tube 21a. It is also possible to configure a structure in which a planar thin sheet photomask is wound onto the outer peripheral surface of the photomask holding tube 21a (annular transparent tube) as the photomask MA, and a photomask pattern composed of a light-shielding layer such as chromium is directly drawn on the outer peripheral surface of the photomask holding tube 21a made of an annular transparent tube and integrated. In this case, the photomask holding tube 21a also functions as a supporting member (photomask supporting member) of the photomask MA.

The guide roller 93 and the drive roller 98 extend in the Y-axis direction parallel to the center line AX1' of the mask holding cylinder 21a. The guide roller 93 and the drive roller 98 are arranged in such a manner that they are circumscribed near the Y-direction end of the mask holding cylinder 21a but do not contact the pattern forming area of the mask MA held by the mask holding cylinder 21a. The drive roller 98 is connected to the drive unit 99. The drive roller 98 rotates the mask holding cylinder 21a around the central axis by transmitting the torque supplied from the drive unit 99 to the mask holding cylinder 21a.

The light source device 13a of this embodiment has the same light source (not shown) and a plurality of illumination optical systems ILa (ILa1 to ILa6) as those of the first embodiment. Part or all of each illumination optical system ILa1 to ILa6 is arranged inside the mask holding tube 21a (annular transparent tube) to illuminate each illumination region IR1 to IR6 on the mask MA held on the outer peripheral surface (mask surface P1) of the mask holding tube 21a from the inside.

Each illumination optical system ILa1 to ILa6 is equipped with a fly-eye lens and a rod integrator, etc., and illuminates each illumination area IR1 to IR6 with uniform illumination through the illumination beam EL1. In addition, the light source can be arranged inside the mask holding tube 21a or outside the mask holding tube 21a. In addition, the light source can also be set separately from the exposure device U3b and guided through a light guide unit such as an optical fiber and a relay lens.

As described in this embodiment, when a transmissive cylindrical mask is used as a mask, mask patterns for display panels of various sizes can be efficiently arranged on the substrate P for exposure by making the shape condition (L/φ) of the mask support tube 21a that holds the mask MA in a cylindrical shape satisfy the relationship described in the previous first embodiment, and the reduction in productivity can be suppressed.

The exposure devices U3, U3a, and U3b of the first, second, and third embodiments described above are all configured to project the mask pattern formed on the cylindrical mask surface P1 (cylindrical wheel 21, mask holding cylinder 21a) onto the substrate P via the projection optical module PLM (PL1 to PL6). However, in the case of a transmissive cylindrical mask (MA) as described in the third embodiment, it can also be configured as a proximity scanning exposure device, which arranges the transmissive cylindrical mask (MA) and the substrate P in proximity in such a manner that a fixed gap (tens to hundreds of μm) is maintained between the outer peripheral surface of the transmissive cylindrical mask (mask surface P1) and the surface of the exposed object, i.e., the substrate P, and synchronously moves the substrate P in one direction while rotating the transmissive cylindrical mask.

In addition, in the exposure devices U3, U3a, and U3b of the first to third embodiments, in order to correspond to the situation where the diameter φ of the cylindrical mask (cylindrical wheel 21, mask holding tube 21a) that can be installed is variable, a mechanism that can adjust the support position (Z position) of the cylindrical mask, or a mechanism that adjusts the state of the optical device in the illumination optical system IL and the projection optical system PL, etc. is provided. In this case, there is a range from the minimum diameter φ1 to the maximum diameter φ2 for the diameter φ of the cylindrical mask that can be installed by the exposure device. Therefore, when the cylindrical mask is manufactured in a manner in which the mask (M, M1 to M4) is arranged on one side or on multiple sides according to the size of the display panel to be manufactured, it is preferred to set the shape and size of the cylindrical mask 21 and the mask holding tube 21a in a manner that satisfies the relationship of 1.3≤L/φ≤3.8 and the relationship of φ1≤φ≤φ2.

<Device Manufacturing Method>

Next, a device manufacturing method will be described with reference to Fig. 22. Fig. 22 is a flowchart showing a device manufacturing method performed by the device manufacturing system.

In the device manufacturing method shown in FIG. 22, first, the function and performance design of the display panel formed by a self-luminous device such as an organic EL is performed, and the required circuit pattern and wiring pattern are designed using CAD or the like (step S201). Next, a cylindrical mask of the required number of layers is produced according to the various patterns of each layer designed using CAD or the like (step S202). At this time, the cylindrical mask is produced so that the relationship between the diameter φ and the length L (La) satisfies 1.3≤L/φ≤3.8 and satisfies the conditions that it can be mounted on an exposure device, and φ1≤φ≤φ2. In addition, a supply reel FR1 is prepared on which a flexible substrate P (resin film, metal foil film, plastic, etc.) serving as a substrate of the display panel is wound (step S203). In addition, the roll-shaped substrate P prepared in this step S203 may be a substrate whose surface has been modified as needed, or a substrate on which a base layer has been formed in advance (for example, microscopic bumps obtained by imprinting), or a substrate on which a photosensitive functional film or a transparent film (insulating material) is pre-laminated.

Next, a base layer composed of electrodes or wirings, insulating films, TFTs (thin film semiconductors) and the like constituting display panel devices is formed on the substrate P, and a light-emitting layer (display pixel portion) composed of self-luminous devices such as organic EL is formed in a stacked manner on the base layer (step S204). In this step S204, it includes: installing a specified cylindrical photomask on the exposure devices U3, U3a, and U3b described in the previous embodiments to expose the photosensitive layer (photoresist layer, photosensitive silane coupling agent layer, etc.) coated on the surface of the substrate P, thereby forming an image (latent image, etc.) of the photomask pattern on the surface; a wet process of forming a metal film pattern (wiring, electrodes, etc.) by chemical plating after developing the substrate P with the photomask pattern as needed; or a printing process of drawing a pattern by conductive ink containing silver nanoparticles, etc.

Next, each display panel device continuously manufactured on the long substrate P in a roll manner is cut into substrates P, and a protective film (an isolation layer for the environment) or a color filter film is attached to the surface of each display panel device to assemble the device (step S205). Next, an inspection process is performed to determine whether the display panel device can work normally or whether it meets the desired performance and characteristics (step S206). In this way, a display panel (flexible display) can be manufactured.

Description of Reference Numerals

1 Device Manufacturing System

2 Substrate supply device

4. Substrate recovery device

5. Upper control device

11 Mask holding mechanism

12.12a Substrate support mechanism

13 Light source device

16 Lower control device

21 Cylindrical wheel

21a Mask holding tube

25 Base plate support cylinder

31 Light Source

32 Light guide components

41 1/4 wavelength plate

51 Collimating lens

52 Compound Eye Lens

53 Condenser lens

54 Cylindrical lens

55 Illumination field aperture

56 Relay lens system

61 First Optical System

62 Second optical system

63 Projection field of view aperture

64 Focus Correction Optics

65 Image switching optical components

66 Magnification correction optical components

67 Rotation correction mechanism

68 Polarization adjustment mechanism

70 first deflection member

71 First lens group

72 First Concave Mirror

80 second deflection member

81 Second lens group

82 Second concave mirror

92 Yubai Department

P Substrate

FR1 Supply Reel

FR2 Recycling Roll

U1～Un Processing device

U3, U3a, U3b Exposure device (substrate processing device)

M, M1, M2, M3 mask

AX1 First axis

AX2 Second axis

P1 Mask surface

P2 Support surface

P7 Intermediate Image Plane

EL1 lighting beam

EL2 Projection Beam

Rm Radius of curvature

Rp Radius of curvature

CL Center plane

PBS Polarization Beam Splitter

IR1～IR6 lighting area

IL1～IL6 Illumination optical system

ILM Illumination Optics Module

PA1～PA7 projection area

PLM Projection Optics Module

Claims (12)

1. A cylindrical mask having a mask pattern formed along a cylindrical surface having a fixed radius relative to a predetermined center line, and mounted on an exposure device in a manner rotatable around the center line, characterized in that: On the cylindrical surface, n rectangular mask areas for display panels are arranged in a manner spaced apart by an interval Sx along the circumferential direction of the cylindrical surface, wherein n≥2, the mask area includes a display screen area having a long side dimension Ld, a short side dimension Lc, an aspect ratio Asp of Ld/Lc, and a long side direction along the center line, and a peripheral circuit area arranged adjacent to the periphery thereof, When the dimension L of the long side direction of the mask area along the center line is set to _e1 times the long side dimension Ld of the display screen area, and the dimension of the short side direction of the mask area along the circumferential direction of the cylindrical surface is set to _e2 times the short side dimension Lc of the display screen area, wherein _e1≥1 , _e2≥1 , the length of the cylindrical surface in the direction of the center line is set to be greater than the dimension L, and when the diameter of the cylindrical surface is set to φ and the pi is set to π, it is set to πφ＝n( _e2 ·Lc+Sx), and further, The diameter φ, the number n, and the interval Sx are set so that the ratio L/φ of the dimension L to the diameter φ falls within the range of 1.3≤L/φ≤3.8. 2. The cylindrical light mask according to claim 1, characterized in that: A cylindrical substrate is provided for holding the mask pattern along the outer peripheral surface having the diameter φ. 3. The cylindrical light mask according to claim 2, characterized in that: The cylindrical substrate is composed of a metal cylindrical body. The mask pattern is configured as a reflective mask pattern in which a high reflection portion and a low reflection portion with respect to illumination light from the exposure device are directly formed on the outer peripheral surface of the cylindrical substrate. 4. The cylindrical light mask according to claim 2, characterized in that: The mask pattern is configured as a reflective sheet mask in which a high reflection portion and a low reflection portion are formed on a thin plate with respect to the illumination light from the exposure device. The reflective sheet mask is maintained in a cylindrical shape along the outer peripheral surface of the cylindrical substrate. The diameter φ is the diameter of the mask surface on which the pattern of the reflective sheet mask is formed. 5. The cylindrical light mask according to claim 4, characterized in that: The cylindrical base material detachably holds the reflective sheet mask in a plate shape that is pre-bent into an arc shape with a fixed radius. 6. The cylindrical light mask according to claim 2, characterized in that: The cylindrical substrate is composed of a transparent ring-shaped cylinder with a fixed thickness. The mask pattern is a transmissive mask pattern in which a pattern serving as a light shielding layer against illumination light from the exposure device is directly drawn and formed on the outer peripheral surface of the transparent tube. 7. The cylindrical light mask according to claim 2, characterized in that: The cylindrical substrate is composed of a transparent ring-shaped cylinder with a fixed thickness. The mask pattern is a planar transmissive sheet mask made of a thin glass plate, and the transmissive sheet mask has a pattern that serves as a light shielding layer for the illumination light from the exposure device. The transmissive sheet mask is bent along the outer circumference of the cylindrical substrate and rolled into a cylindrical shape. The diameter φ is the diameter of the mask surface on which the pattern of the transmission-type sheet mask is formed. 8. The cylindrical light mask according to claim 7, characterized in that: The transmissive sheet mask has a non-pattern forming area where the pattern is not formed. The cylindrical substrate detachably holds the transmission-type mask pattern in the non-pattern forming region. 9. The cylindrical light mask according to any one of claims 1 to 8, characterized in that: The relationship between the length L and the diameter φ is set to further satisfy L/φ≤2.6. 10. The cylindrical light mask according to any one of claims 1 to 8, characterized in that: The mask pattern includes a pattern of electrodes or wirings for forming TFTs for driving each pixel, and a pattern of each pixel in the display screen region, wherein each pixel is arranged in the display screen region. 11. The cylindrical light mask according to any one of claims 1 to 8, characterized in that: The display screen area corresponds to a display screen of a liquid crystal display or an organic EL display. 12. The cylindrical light mask according to any one of claims 1 to 8, characterized in that: The ratio of the long side dimension Ld to the short side dimension Lc of the display screen area is 16:9 or 2:1.