TW202032294A - Device production method and exposure method - Google Patents

Abstract

The present invention provides a substrate processing apparatus and a device manufacturing method capable of highly productively producing a high-quality substrate. The substrate processing apparatus and device manufacturing method are provided with a first support member for supporting one of a mask and a substrate along a first surface curved in the shape of a cylindrical surface with a prescribed curvature in one of an illumination area and a projection area, a second support member for supporting the other of the mask and the substrate along a prescribed second surface in the other of the illumination area and the projection area, and a movement mechanism for rotating the first support member to move, in a scanning exposure direction, either of the mask and the substrate supported by the first support member. A projection optical system projects, into the projection area, a beam having a best focus position included at two locations on the exposure surface of the substrate in the scanning exposure direction.

Description

Scanning exposure device and scanning exposure method

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

There is an element manufacturing system that manufactures display elements such as liquid crystal displays or various elements such as semiconductors. The component manufacturing system includes a substrate processing device such as an exposure device. The substrate processing device projects the image of the pattern formed on the mask (or reticle) arranged in the illumination area to the substrate etc. arranged in the projection area, and exposes the pattern on the substrate. The mask used in the substrate processing apparatus is generally a flat one, and in order to continuously scan and expose a plurality of device patterns on the substrate, a cylindrical one is also known (Patent Document 1).

In addition, as a substrate processing apparatus, there is a projection exposure apparatus described in Patent Document 2. The projection exposure apparatus described in Patent Document 2 has: a substrate holder that holds the photosensitive substrate on the substrate stage so that the surface of the photosensitive substrate in the one-dimensional movement direction and the pattern image projected by the projection optical system are optimally formed The surface is relatively tilted by a certain amount; and the holder drive means is linked to the one-dimensional movement of the substrate stage by moving along the direction of the photosensitive substrate during the scanning exposure to move the substrate holder in the projection optical system The direction of the optical axis. The projection exposure device, with the above structure, can change the focus state of the light beam projected on the exposure surface of the photosensitive substrate according to the position of the scanning exposure in one-dimensional direction.

[Advanced Technical Literature] [Patent Document 1] International Publication No. 2008/029917 [Patent Document 2] Japanese Patent No. 2830492

The problem to be solved by the invention

As described in Patent Document 2, by performing exposure while changing the focus state, the relationship between the light beam projected by the projection optical system and the exposure surface due to the deviation of the relative relationship between the mask and the substrate or the deviation of the optical system occurs When changing, the exposure can also be performed in the focused state including the best focus position. Thereby, the change in contrast of the image exposed to the photosensitive substrate (photoresist layer) can be suppressed.

However, the projection exposure apparatus described in Patent Document 2 uses a substrate holder to tilt the substrate with respect to the projection optical device (projection optical system). Therefore, the adjustment (control) of the relative position becomes complicated. In particular, in the step-and-scan method of scanning the mask and the substrate relative to each of a plurality of exposure areas (each irradiation) on the substrate to move the substrate step by step, it is necessary to scan each exposure area on the substrate The high-speed exposure repeatedly controls the tilt of the substrate holder and the movement to the focusing direction, and the control becomes complicated and causes vibration.

In addition, in a substrate processing apparatus of the scanning exposure method, if the width of the exposure area on the substrate in the scanning exposure direction is small, the amount of exposure given to the photosensitive substrate becomes small. Therefore, it is necessary to increase the illuminance per unit area of the exposure light projected on the exposure area on the substrate or the speed of delayed scanning exposure. Conversely, if the width of the exposed area on the substrate in the scanning exposure direction is increased, the quality of the formed pattern (transfer fidelity) may sometimes decrease.

The aspect of the present invention aims to provide a substrate processing apparatus, a device manufacturing method, and an exposure method that can produce high-quality substrates with high productivity. Means to solve the problem

According to a first aspect of the present invention, there is provided a substrate processing apparatus including a projection optical system for projecting a light beam from a pattern of a mask arranged in an illumination light illumination area onto a projection area where a substrate is arranged, and comprising: a first support member, It supports one of the mask and the substrate in one of the illumination area and the projection area along the first surface curved into a cylindrical surface with a predetermined curvature; the second support member is Supporting the other of the photomask and the substrate in a manner along the predetermined second surface in the other of the illumination area and the projection area; and a moving mechanism that rotates the first support member to Move any one of the mask and the substrate supported by the first supporting member in the scanning exposure direction; the projection optical system is on the exposure surface of the substrate, and the scanning exposure direction includes two best focus The position of the light beam is projected on the aforementioned projection area.

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

According to a third aspect of the present invention, there is provided an exposure method for projecting a light beam from a pattern of a mask arranged in the illumination area of the illumination light onto the projection area of the arrangement substrate, which includes: in the aforementioned illumination area and the aforementioned projection area The movement of one of the mask and the substrate is supported in one area along the first surface curved into a cylindrical shape with a predetermined curvature; in the other area of the illumination area and the projection area The action of supporting the other of the mask and the substrate in the manner of the predetermined second surface; making any one of the mask and the substrate supported by the first surface rotate along the first surface, An action of moving any one of the mask and the substrate supported by the first surface in the scanning exposure direction; and on the exposure surface of the substrate, beams that include two best focus positions in the scanning exposure direction are projected In the aforementioned projection area. Invention effect

According to the aspect of the present invention, by projecting light beams including two best focus positions on the projection area in the scanning exposure direction of the exposure surface of the substrate, a high-quality substrate can be produced with high productivity.

The mode (embodiment) for implementing the present invention will be described in detail with reference to the drawings as follows. The present invention is not limited to the content described in the following embodiments. In addition, the constituent elements described below include those easily conceived by those having ordinary knowledge in the technical field to which the invention belongs, and also include substantially the same thing. In addition, the constituent elements described below can be combined as appropriate. In addition, various omissions, substitutions, or changes of constituent elements can be made without departing from the scope of the present invention. For example, in the following embodiment, although the case of manufacturing a flexible display is described as an element system, it is not limited to this. As components, wiring boards, semiconductor substrates, etc. can also be manufactured.

[First Embodiment] The substrate processing apparatus of the first embodiment is an exposure apparatus that applies exposure processing to a substrate. In addition, the exposure device is assembled in a component manufacturing system that applies various treatments to the exposed substrate to manufacture components. First, the component manufacturing system will be explained.

＜Component manufacturing system＞ Fig. 1 is a diagram showing the configuration of the component manufacturing system of the first embodiment. The component manufacturing system 1 shown in Figure 1 is a production line (flexible display production line) for manufacturing flexible displays as components. As the flexible display, for example, there is an organic EL display. This component manufacturing system 1 sends out the substrate P from the supply reel FR1 that winds the flexible substrate P into a roll shape, and continuously applies various treatments to the sent substrate P, and then the processed substrate As a flexible element, P is wound on the recycling reel FR2, the so-called roll to roll (Roll to Roll) method. The component manufacturing system 1 of the first embodiment shows that the substrate P as a film-like sheet is sent out from the supply roll FR1, and the substrate P sent out from the supply roll FR1 is sequentially passed through n processing devices U1. Examples of U2, U3, U4, U5, ...Un, wound up to the recycling reel FR2. First, the substrate P to be processed by the component manufacturing system 1 will be described.

The substrate P uses, for example, a foil made of a resin film, stainless steel, or other metals or alloys. The material of the resin film includes, for example, polyethylene resin, polypropylene resin, polyester resin, ethylene ethylene copolymer resin, polyvinyl chloride resin, cellulose resin, polyamide resin, polyimide resin, and polycarbonate resin. , Polystyrene resin, vinyl acetate resin, one or more than two kinds.

For the substrate P, it is better to select, for example, the coefficient of thermal expansion is significantly larger, and the amount of deformation that can be generated by heat during various processes performed on the substrate P can be substantially ignored. The coefficient of thermal expansion, for example, can be set to be smaller than the threshold of the corresponding process temperature by mixing inorganic fillers into the resin film. The inorganic filler may be, for example, titanium oxide, zinc oxide, aluminum oxide, silicon oxide, and the like. In addition, the substrate P may be a single layer of ultra-thin glass with a thickness of about 100 μm manufactured by a float method or the like, or a laminate of the above-mentioned resin film, foil, etc., bonded to this ultra-thin glass.

The substrate P configured in this manner is wound into a roll shape to become a supply roll FR1, and this supply roll FR1 is mounted in the component manufacturing system 1. The component manufacturing system 1 equipped with the supply reel FR1 repeatedly performs various processes for manufacturing one component on the substrate P sent from the supply reel FR1. Therefore, the processed substrate P becomes a state where a plurality of components are connected. In other words, the substrate P sent out from the supply roll FR1 is a substrate for picking up multiple sides. In addition, the substrate P may be a surface modified and activated by a predetermined pre-treatment in advance, or a fine partition structure (concave-convex structure) for precise patterning is formed on the surface by a marking method.

The processed substrate P is wound into a roll shape to be recovered as a recovery roll FR2. The recycling roll FR2 is installed in a cutting device not shown. Equipped with a cutting device for the recycling roll FR2, the processed substrate P is divided (cut) into individual components, which are then divided into multiple components. 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 strip) is more than 10 m. Of course, the size of the substrate P is not limited to the above-mentioned size.

Next, the component manufacturing system 1 will be described with reference to FIG. 1. In Figure 1, the X direction, Y direction and Z direction form an orthogonal coordinate system. The X direction is the direction in which the supply roll FR1 and the recovery roll FR2 are connected in the horizontal plane, and is the left-right direction in FIG. 1. The Y direction is the direction orthogonal to the X direction in the horizontal plane, which is the front and back direction in Figure 1. The Y direction is the axial direction of the supply roll FR1 and the recovery roll FR2. The Z direction is the vertical direction, which is the up and down direction in Figure 1.

The component manufacturing system 1 is provided with a substrate supply device 2 for supplying substrates P, processing devices U1 to Un for performing various processes on the substrate P supplied by the substrate supply device 2, and for recycling the substrates P processed by the processing devices U1 to Un The substrate recovery device 4 and the upper control device 5 of each device of the control element manufacturing system 1.

On the substrate supply device 2, the supply roll FR1 is rotatably mounted. The substrate supply device 2 has a drive roller R1 that sends out the substrate P from the installed supply roll FR1, and an edge position controller EPC1 that adjusts the position of the substrate P in the width direction (Y direction). The driving roller R1 rotates while sandwiching the front and back surfaces of the substrate P, and sends the substrate P from the supply roll FR1 to the conveyance direction of the recovery roll FR2, thereby supplying the substrate P to the processing devices U1-Un. At this time, the edge position controller EPC1 moves the substrate P in the width direction such that the position of the end (edge) of the substrate P in the width direction is within a range of ± tens of μm to tens of μm relative to the target position. To correct the position of the substrate P in the width direction.

The substrate recovery device 4 is equipped with a reel FR2 for recovery in a rotatable manner. The substrate recovery device 4 includes a drive roller R2 that pulls the processed substrate P to the side of the recovery roll 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 sandwiching the front and back surfaces of the substrate P with the driving roller R2, pulls the substrate P in the conveying direction, and rotates the recovery roll FR2 to wind the substrate P accordingly. 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 unevenness in the width direction end (edge) of the substrate P in the width direction.

The processing device U1 is a coating device that coats the surface of the substrate P supplied from the substrate supply device 2 with a photosensitive functional liquid. As the photosensitive functional liquid, for example, a photoresist, a photosensitive silane coupling material (a liquid-philic modifying material), a photosensitive plating reduction material, a UV curable resin liquid, etc. are used. The processing device U1 is provided with a coating mechanism Gp1 and a drying mechanism Gp2 in order from the upstream side in the conveying direction of the substrate P. The coating mechanism Gp1 has a pressure roller DR1 wound around the substrate P and a coating roller DR2 facing the pressure roller DR1. The coating mechanism Gp1 clamps the substrate P with the pressure roller DR1 and the coating roller DR2 while winding the supplied substrate P around the pressure roller DR1. Next, the coating mechanism Gp1 rotates the pressing roller DR1 and the coating roller DR2 to apply the photosensitive functional liquid with the coating roller DR2 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 to form photosensitivity on the substrate P Functional layer.

The processing device U2 is a heating device that heats the substrate P conveyed from the processing device U1 to a predetermined temperature (for example, several tens 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 this order from the upstream side in 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 (air turn bars) inside, and the plurality of rollers and a plurality of air turn bars constitute a transport path of the substrate P. A plurality of rollers are arranged in a manner of rolling on the back surface of the substrate P, and a plurality of air inversion rods are arranged on the surface side of the substrate P in a non-contact state. A plurality of rollers and a plurality of air inverting rods lengthen the conveyance path of the substrate P, and present a meandering conveyance path. The substrate P in the heating chamber HA1 is heated to a predetermined temperature while being conveyed along a meandering 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 inside, and the plurality of rollers are arranged in a serpentine conveying path in order to lengthen the conveying path of the substrate P similarly to the heating chamber HA1. The substrate P in the cooling chamber HA2 is cooled while being transported along the meandering transport path. A drive roller R3 is provided on the downstream side in the conveying direction of the cooling chamber HA2, and the drive roller R3 rotates while clamping the substrate P passing through the cooling chamber HA2, thereby supplying the substrate P to the processing device U3. In addition, the heating of the substrate P by the heating chamber HA1 can be set to not when the substrate P is a resin film such as PET (polyethylene terephthalate) or PEN (polyethylene naphthalate). Exceeds its glass transition temperature.

The processing device (substrate processing device) U3 is an exposure device for projecting and exposing patterns such as the circuit or wiring of the display for the substrate (photosensitive substrate) P supplied from the processing device U2 and having a photosensitive functional layer formed on the surface. The details will be described later. The processing device U3 illuminates the reflective mask M with an illuminating beam, and projects and exposes the substrate P to the substrate P by the projection beam reflected by the illuminating beam by the mask M. The processing device U3 has a drive roller R4 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 R4 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 moving the substrate P toward the substrate support reel (rotating reel (also Called rotating reel) supply.

The edge position controller EPC3 has the same configuration 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 (the substrate support roll) becomes the target position. In addition, the processing device U3 has two sets of drive rollers R5 and R6 that send the substrate P to the downstream side in the conveying direction while slackening the substrate P after exposure. The two sets of drive rollers R5 and R6 are separated in the conveying direction of the substrate P Follow the established interval configuration. The driving roller R5 clamps and rotates the upstream side of the conveyed substrate P, and the driving roller R6 rotates the downstream side of the conveyed substrate P clamped, thereby supplying the substrate P to the processing device U4. At this time, since the substrate P has been given slack, it can absorb the change in the conveying speed that occurs on the downstream side of the driving roller R6 in the conveying direction, and can cut off the influence of the change in the conveying speed on the exposure processing of the substrate P. In addition, the processing device U3 is provided with an alignment microscope AM1 for aligning the image of a part of the mask pattern of the mask M with the substrate P and detecting the alignment marks and the like formed on the substrate P in advance. , AM2.

The processing device U4 is a wet processing device that performs wet development processing and electroless plating processing on the exposed substrate P conveyed from the processing device U3. The processing device U4 has three processing tanks BT1, BT2, BT3 stepped in the vertical direction (Z direction), and a plurality of rollers that transport the substrate P inside. The plurality of rollers are arranged such that the substrate P sequentially passes through the conveying path inside the three processing tanks BT1, BT2, and BT3. A driving roller R7 is provided on the downstream side in the conveying direction of the processing tank BT3, and the driving roller R7 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, the processing device U5 is a drying device that dries the substrate P conveyed from the processing device U4. The processing device U5 removes liquid droplets or mist (MIST) attached to the substrate P by wet processing in the processing device U4, and adjusts the moisture content of the substrate P to a predetermined moisture content. The substrate P dried by the processing device U5 is transported to the processing device Un after passing through a plurality of processing devices. After being processed by the processing device Un, the substrate P is wound on the recovery reel FR2 of the substrate recovery device 4.

The upper control device 5 comprehensively controls the substrate supply device 2, the substrate recovery device 4, and a 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, in synchronization with the transportation of the substrate P, controls a plurality of processing devices U1 to Un to perform various processing on the substrate P.

＜Exposure equipment (substrate processing equipment)＞ Next, the configuration of the exposure apparatus (substrate processing apparatus) as the processing apparatus U3 of the first embodiment will be described with reference to FIGS. 2 to 4. Fig. 2 is a diagram showing the overall configuration of the exposure apparatus (substrate processing apparatus) of the first embodiment. FIG. 3 is a diagram showing the arrangement of the illumination area and the projection area of the exposure device shown in FIG. 2. 4 is a diagram showing the configuration of the illumination optical system and the projection optical system of the exposure device shown in FIG. 2. Hereinafter, the processing device U3 is referred to as an exposure device U3.

The exposure device U3 shown in FIG. 2 is a so-called scanning exposure device, which conveys the substrate P in the conveying direction (scanning direction) while projecting the image of the mask pattern formed on the outer peripheral surface of the cylindrical mask M. To the surface of the substrate P. In addition, FIG. 2 is an orthogonal coordinate system in which the X direction, the Y direction, and the Z direction are orthogonal, and it is the same orthogonal coordinate system as in FIG. 1.

First, the photomask M used in the exposure device U3 will be described. The mask M is a reflection type mask using a metal cylindrical body, for example. The mask M is formed as a cylindrical body having an outer peripheral surface (circumferential surface) of a curvature radius Rm centered on the first axis AX1 extending in the Y direction, and has a certain thickness in the radial direction. The circumferential surface of the mask M is a surface P1 formed with a predetermined mask pattern. The surface P1 of the mask M includes a high reflection part that reflects the light beam in a predetermined direction with high efficiency, and a reflection suppression part that does not reflect the light beam in the predetermined direction or reflects with low efficiency. The mask pattern is formed with a high reflection part and a reflection suppression part. Therefore, the reflection suppression part may absorb light, may transmit light, or may reflect (e.g., scatter) outside a predetermined direction. The mask M here can be made of a material that absorbs light or a material that transmits light. The exposure device U3 can use a photomask made of a metal cylindrical body as the photomask M of the above structure. Therefore, the exposure device U3 can use an inexpensive photomask for exposure.

In addition, the mask M may be formed with all or a part of the panel pattern corresponding to one display element, or may be formed with the panel pattern corresponding to a plurality of display elements. In addition, the mask M may have a plurality of panel patterns formed repeatedly in the circumferential direction around the first axis AX1, or a small panel pattern may be formed repeatedly in a direction parallel to the first axis AX1. In addition, the mask M may be a pattern for a panel on which the first display element is formed and a pattern for a second display element that is different in size from the first display element. In addition, the mask M may be a circumferential surface having a curvature radius Rm centered on the first axis AX1, and is not limited to a cylindrical shape. For example, the mask M may be an arc-shaped plate with a circumferential surface. In addition, the mask M may have a thin plate shape, or the thin plate-shaped mask M may be bent and attached to the cylindrical member so as to follow the circumferential surface.

Next, the exposure apparatus U3 shown in FIG. 2 will be explained. Exposure device U3, in addition to the aforementioned drive rollers R4 to R6, edge position controller EPC3, and alignment microscopes AM1, AM2, also has a mask holding mechanism 11, a substrate support mechanism 12, an illumination optical system IL, a projection optical system PL, And the lower control device 16. The exposure device U3 is guided by passing the illumination light emitted from the light source device 13 through the illumination optical system IL and the projection optical system PL, and projects the light beam of the pattern of the mask M held by the mask holding mechanism 11 to the substrate The substrate P held by the supporting 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 component manufacturing system 1. In addition, the lower control device 16 may 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 has a mask holding cylinder (mask holding member) 21 for holding the mask M, and a first driving unit 22 for rotating the mask holding cylinder 21. The mask holding cylinder 21 holds the mask M with the first axis AX1 of the mask M as the center of rotation. The first driving unit 22 is connected to the lower control device 16 and rotates the mask holding cylinder 21 with the first axis AX1 as the rotation center.

In addition, although the mask holding mechanism 11 uses the mask holding cylinder 21 to hold the cylindrical mask M, it is not limited to this structure. The mask holding mechanism 11 can also wind and hold the thin plate-shaped mask M along the outer peripheral surface of the mask holding cylinder 21. In addition, the mask holding mechanism 11 may also detachably hold the mask M of the arc-shaped plate material on the outer peripheral surface of the mask holding cylinder 21.

The substrate support mechanism 12 includes a substrate support cylinder 25 that supports and rotates the substrate P with a cylindrical outer peripheral surface, a second drive unit 26 that rotates the substrate support cylinder 25, and a pair of air turn bars ATB1, ATB2, and a pair of guide rollers 27, 28. The substrate support cylinder 25 is formed in 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 a plane passing through the first axis AX1 and the second axis AX2 is the center plane CL. A part of the circumferential surface of the substrate supporting cylinder 25 is a supporting surface P2 for supporting the substrate P. In other words, the substrate supporting cylinder 25 supports the substrate P by winding the substrate P on its supporting surface P2. 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 center of rotation.

The pair of air inversion rods ATB1 and ATB2 are provided on the upstream and downstream sides of the substrate P in the conveying direction with the substrate support cylinder 25 interposed therebetween. A pair of air inversion rods ATB1 and ATB2 are provided on the surface side of the substrate P, and are arranged below the support surface P2 of the substrate support cylinder 25 in the vertical direction (Z direction). The pair of guide rollers 27 and 28 are provided on the upstream and downstream sides of the substrate P in the conveying direction via a pair of air inversion rods ATB1 and ATB2. A pair of guide rollers 27 and 28, one of the guide roller 27 guides the substrate P transported from the drive roller R4 to the air inversion bar ATB1, and the other guide roller 28 guides the substrate from the air inversion bar ATB2 P is guided to the driving roller R5.

In summary, the substrate support mechanism 12 guides the substrate P transported from the driving roller R4 to the air inversion bar ATB1 by the guide roller 27, and guides the substrate P passed through the air inversion bar ATB1 into the substrate support cylinder 25. The substrate support mechanism 12 rotates the substrate support cylinder 25 by the second drive unit 26, so that the substrate P introduced into the substrate support cylinder 25 is supported by the support surface P2 of the substrate support cylinder 25 while being transported to the air. Rod ATB2. The substrate support mechanism 12 guides the substrate P conveyed to the air inversion lever ATB2 to the guide roller 28 by the air inversion lever ATB2, and guides the substrate P that has passed the guide roller 28 to the driving roller R5.

At this time, the lower control device 16 connected to the first driving portion 22 and the second driving portion 26 causes the mask holding cylinder 21 and the substrate supporting cylinder 25 to rotate synchronously at a predetermined rotation speed ratio, and the mask M is formed The image of the mask pattern on the surface P1 is continuously and repeatedly projected and exposed on the surface of the substrate P (the surface curved along the circumferential surface) wound on the support surface P2 of the substrate support cylinder 25.

The light source device 13 emits an illumination light beam EL1 that illuminates the mask M. The light source device 13 has a light source 31 and a light guide member 32. The light source 31 is a light source emitting a predetermined wavelength. The light source 31 may use a light source such as a mercury lamp, a laser diode, a light emitting diode (LED), or the like. The illumination light emitted by the light source 31 is, for example, the bright line (g-line, h-line, i-line, etc.) emitted from the light source, far ultraviolet light (DUV light) such as KrF excimer laser light (wavelength 248nm), and ArF excimer laser light (Wavelength 193nm) and so on. The light source 31 here preferably emits an illumination light beam EL1 having a wavelength below the i-line (wavelength of 365 nm). As the light source 31 that generates the illumination beam EL1 with a wavelength below the i-line, it is possible to use laser light from YAG laser (3rd harmonic laser) (wavelength of 355nm), YAG laser (4th harmonic laser) ) Laser light emitted from a KrF excimer laser (wavelength of 266nm), or laser light emitted from a KrF excimer laser (wavelength of 248nm), etc.

The light guide member 32 guides the illumination light beam EL1 emitted from the light source 31 to the illumination optical system IL. The light guide member 32 is composed of a relay module using an optical fiber or a mirror. In addition, when the light guide member 32 is provided with a plurality of illumination optical systems IL, it separates the illumination light beam EL1 from the light source 31 into a plurality of pieces, and then guides the plurality of illumination light beams EL1 to the plurality of illumination optical systems IL. In addition, the light guide member 32, the light guide member 32 of this embodiment, causes the illumination light beam EL1 emitted from the light source 31 to be light in a predetermined polarization state and enters the polarization beam splitter PBS. The polarization beam splitter PBS of this embodiment reflects the linearly polarized light beam as S-polarized light, and transmits the linearly polarized light beam as P-polarized light. Therefore, the light source device 13 emits the illumination light beam EL1 that enters the polarization beam splitter PBS into linearly polarized (S-polarized) illumination light beam EL1.

The light source device 13 emits a polarized laser with the same wavelength and phase to the polarizing 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 plane preservation fiber as the light guide member 32 to maintain the polarization state of the laser light output from the light source device 13 to guide the light. In addition, for example, an optical fiber may guide the light beam output from the light source 31, and a polarizing plate may be used to polarize the light output from the optical fiber. That is, when the light source device 13 guides the randomly polarized light beam, the polarizing plate can also be used to polarize the randomly polarized light beam, or the polarizing beam splitter PBS can be used to split the light beams into the P-direction and S-direction beams to transmit the polarized light. The light of the beam splitter PBS is used as the light beam that enters the illumination optical system IL of one system, and the light reflected by the polarization beam splitter PBS is used as the light beam that is incident on the illumination optical system IL of the other system. In addition, the light source device 13 may 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 FIG. 3, the exposure apparatus U3 of the first embodiment assumes a so-called multi-lens exposure apparatus. In addition, FIG. 3 shows a plan view of the illumination area IR on the mask M held by the mask holding cylinder 21 viewed from the -Z side (the left diagram in FIG. 3), and the substrate support cylinder 25 viewed from the +Z side The top view of the projection area PA on the supported substrate P (the right image in FIG. 3). The symbol Xs in FIG. 3 represents the moving direction (rotation direction) of the mask holding cylinder 21 and the substrate supporting cylinder 25. The exposure device U3 of the multi-lens method is attached to a plurality of (for example, 6 in the first embodiment) illumination areas IR1 to IR6 on the mask M, respectively illuminating the illumination light beam EL1, and each illumination light beam EL1 is placed in each illumination area IR1 The plurality of projection light beams EL2 obtained by reflection of ~IR6 are projected and exposed to a plurality of projection areas PA1 to PA6 on the substrate P (for example, 6 in the first embodiment).

First, a plurality of illumination areas IR1 to IR6 illuminated by the illumination optical system IL will be described. As shown in Fig. 3, a plurality of illumination areas IR1 to IR6 are arranged on the mask M on the upstream side in the rotation direction with the center plane CL interposed between the first illumination area IR1, the third illumination area IR3, and the fifth illumination area IR5. 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 direction. Each of the illumination areas IR1 to IR6 is an area having a slender trapezoid with parallel short sides and long sides extending in the axial direction (Y direction) of the mask M. At this time, each of the trapezoidal illumination areas IR1 to IR6 forms an area whose short side is on the side of the center plane CL and its long side is on the outside. The first illumination area IR1, the third illumination area IR3, and the fifth illumination area IR5 are arranged at predetermined intervals in the axial direction. In addition, the second illumination area IR2, the fourth illumination area IR4, and the sixth illumination area IR6 are also 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. The illumination areas IR1 to IR6, viewed from the circumferential direction (X direction) of the mask M, are arranged in such a way that the triangles of the hypotenuses of adjacent trapezoidal illumination areas overlap. In addition, in the first embodiment, although the illumination areas IR1 to IR6 are formed as trapezoidal areas, they may be formed as rectangular areas.

In addition, the mask M has a pattern formation area A3 in which a mask pattern is formed, and a pattern non-formation area A4 in which a mask pattern is not formed. The pattern non-formation area A4 is a non-reflection area that absorbs the illumination light beam EL1, and is arranged to surround the pattern formation area A3 in a frame shape. The first to sixth illumination areas IR1 to IR6 are arranged to cover the full width of the pattern formation area A3 in the Y direction.

The illumination optical system IL system is provided with a plurality of illumination regions IR1 to IR6 (for example, 6 in the first embodiment). The illumination light beam EL1 from the light source device 13 is incident on a plurality of illumination optical systems (divided cover optical systems) IL1 to IL6, respectively. The illumination optical systems IL1 to IL6 respectively guide the illumination light beam EL1 incident from the light source device 13 to the illumination regions IR1 to IR6. That is, the first illumination optical system IL1 guides the illumination light beam EL1 to the first illumination area 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 areas IR2. ~IR6. A plurality of illumination optical systems IL1 to IL6 are arranged on the side where the first, third, and fifth illumination regions IR1, IR3, IR5 are arranged (the left side of Fig. 2) across the center plane CL, and the first illumination optical system IL1 and the third are arranged The illumination optical system IL3 and the fifth illumination optical system IL5. The first illumination optical system IL1, the third illumination optical system IL3, and the fifth illumination optical system IL5 are arranged at a predetermined interval in the Y direction. In addition, a plurality of illumination optical systems IL1 to IL6 are arranged on the side where the second, fourth, and sixth illumination regions IR2, IR4, and IR6 are arranged across the center plane CL (the right side of Fig. 2), and the second illumination optical system IL2 is arranged The fourth illumination optical system IL4 and the sixth illumination optical system IL6. The second illumination optical system IL2, the fourth illumination optical system IL4, and the sixth illumination optical system IL6 are arranged at a predetermined interval in the Y direction. At this time, the second illumination optical system IL2 is arranged in the axial direction between the first illumination optical system IL1 and the third illumination optical system IL3. Similarly, the third illumination optical system IL3, the fourth illumination optical system IL4, and the fifth illumination optical system IL5 are arranged in the axial direction between the second illumination optical system IL2 and the fourth illumination optical system IL4, and the third illumination optical system Between IL3 and the fifth illumination optical system IL5, and between the fourth illumination optical system IL4 and the sixth illumination optical system IL6. In addition, the first illumination optical system IL1, the third illumination optical system IL3, and the fifth illumination optical system IL5, the second illumination optical system IL2, the fourth illumination optical system IL4, and the sixth illumination optical system IL6 are symmetrical when viewed from the Y direction. Configuration.

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

The illumination optical system IL, in order to illuminate the illumination area IR (first illumination area IR1) with uniform illuminance, is adapted to the Kohler illumination method that converts the illumination light beam EL1 from the light source device 13 into a surface light source image of a plurality of point light sources assembled in a planar manner . In addition, the illumination optical system IL is an epi-illumination system using a polarizing beam splitter PBS. The illumination optical system IL has an illumination optical module ILM, a polarization beam splitter PBS, and a quarter wave plate 41 in order from the incident side of the illumination light beam EL1 from the light source device 13.

As shown in Fig. 4, 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, and an illumination field diaphragm in order from the incident side of the illumination light beam EL1. 55. A plurality of relay lenses 56 are arranged on the first optical axis BX1. The collimator lens 51 is provided on the emission side of the light guide member 32 of the light source device 13. The optical axis of the collimator lens 51 is arranged on the first optical axis BX. The collimator lens 51 illuminates the entire surface of the incident side of the fly eye lens 52. The fly-eye lens 52 is provided on the exit side of the collimator lens 51. The center of the emission side surface of the fly-eye lens 52 is arranged on the first optical axis BX1. The fly-eye lens 52 divides the illuminating light beam EL1 from the collimator lens 51 into a plurality of point light sources, and superimposes the light from each point light source and enters the condenser lens 53 described later.

At this time, the exit side surface of the fly-eye lens 52 that generates the point light source image is arranged with the first concave mirror by various lenses from the fly-eye lens 52 through the illumination field diaphragm 55 to the first concave mirror 72 of the projection optical system PL described later The pupil plane where the reflecting plane of 72 is located is optically conjugate. The condenser lens 53 is provided on the exit side of the fly-eye lens 52, and its optical axis is arranged on the first optical axis BX1. The condenser lens 53 transmits the light (illumination light beam EL1) from each point light source of the fly-eye lens 52 through the cylindrical lens 54 and irradiates it so as to overlap on the illumination field diaphragm 55. In the case where there is no cylindrical lens 54, the principal rays of the illumination light beam EL1 reaching each point on the illumination field diaphragm 55 are all parallel to the first optical axis BX1. However, by the action of the cylindrical lens 54, the principal rays of the illumination light beam EL1 illuminating the illumination field diaphragm 55 become a telecentric state parallel to each other in the Y direction in FIG. 4 (also parallel to the first optical axis BX1). The XZ plane is in a non-telecentric state in which the inclination relative to the first optical axis BX1 is sequentially different in accordance with the image height position.

The cylindrical lens 54 is a plano-convex cylindrical lens whose entrance side is a flat surface and the exit side is a convex surface, and is arranged adjacent to the entrance side of the illumination field diaphragm 55. The optical axis of the cylindrical lens 54 is arranged on the first optical axis BX1, and the generatrix of the convex cylindrical surface of the emission side of the cylindrical lens 54 is set parallel to the Y axis in FIG. 4. Thereby, the principal rays of the illumination beam EL1 immediately after passing through the cylindrical lens 54 are parallel to the first optical axis BX1 in the Y direction, and go to a certain point on the first optical axis BX1 in the XZ plane (strictly coming from It is said that the line extending in the Y direction orthogonal to the first optical axis BX1) converges.

The opening of the illumination field stop 55 is formed into a trapezoid (rectangular) having the same shape as the illumination area IR, and the center of the opening of the illumination field stop 55 is arranged on the first optical axis BX1. At this time, the illumination field diaphragm 55 is provided by the relay lens (imaging system) 56 from the illumination field diaphragm 55 to the cylindrical surface P1 of the mask M, the polarization beam splitter PBS, and the quarter wave plate 41 and so on, are arranged on a surface that is optically conjugate with the illumination area IR on the mask M. The relay lens 56 is provided on the emission side of the illumination field diaphragm 55. The optical axis of the relay lens 56 is arranged on the first optical axis BX1. The relay lens 56 transmits the illumination light beam EL1 passing through the opening of the illumination field diaphragm 55 through the polarization beam splitter PBS and the quarter wave plate 41 and irradiates the cylindrical surface P1 (illumination area IR) of the mask M.

The polarizing 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 as S-polarized light on the wavefront splitting surface, and transmits the linearly polarized light beam as P-polarized light. Here, the illumination light beam EL1 that enters the polarization beam splitter PBS is a linearly polarized light beam of S polarization, and the reflected light from the mask M (projection light beam EL2) that enters the polarization beam splitter PBS is 1/4 wavelength The plate 41 becomes a linearly polarized beam of P-polarized light.

Thereby, the polarizing beam splitter PBS reflects the illumination light beam EL1 incident on the wavefront dividing surface from the illumination optical module ILM, and transmits the projection light beam EL2 reflected on the mask M and incident on the wavefront dividing surface. Although the polarizing beam splitter PBS preferably reflects all of the illumination light beam EL1 incident on the wavefront dividing surface, it can also reflect most of the illumination light beam EL1 incident on the wavefront dividing surface, so that part of it is transmitted or absorbed on the wavefront dividing surface . Similarly, the polarizing beam splitter PBS preferably transmits all of the projection light beam EL2 incident on the wavefront dividing surface, but it can also transmit most of the projection light beam EL2 incident on the wavefront dividing surface while reflecting a part or absorb.

The 1/4 wave plate 41 is arranged between the polarization beam splitter PBS and the mask M, and converts the illumination light beam EL1 reflected by the polarization beam splitter PBS from linearly polarized light (S-polarized light) to circularly polarized light. The circularly polarized illumination beam EL1 illuminates the mask M. The 1/4 wave plate 41 converts the circularly polarized projection light beam EL2 reflected on the mask M into linearly polarized light (P polarized light).

Here, the illumination optical system IL treats the mask in such a way that the chief ray of the projection beam EL2 reflected by the illumination area IR on the surface P1 of the mask M becomes a telecentric state regardless of the Y direction and the XZ plane. The illumination area of M is IR illumination illumination beam EL1. The state will be explained with reference to FIG. 5.

5 is an exaggerated display of the state of the illumination light beam EL1 irradiated on the illumination area IR on the mask M and the projection light beam EL2 reflected in the illumination area IR in the XZ plane (plane perpendicular to the first axis AX1). As shown in FIG. 5, the above-mentioned illumination optical system IL irradiates the illumination area IR of the mask M so that the chief ray of the projection beam EL2 reflected in the illumination area IR of the mask M becomes telecentric (parallel system) The chief ray of the illumination beam EL1 intentionally becomes a non-telecentric state in the XZ plane, and becomes a telecentric state in the Y direction.

Such characteristics of the illumination light beam EL1 are given by the cylindrical lens 54 shown in FIG. 4. Specifically, a circle that passes through the center point Q1 of the illumination area IR on the surface P1 of the mask M and faces the first axis AX1 and 1/2 of the radius Rm of the surface P1 of the mask M is set. At the intersection point Q2 of (Rm/2), the curvature of the convex cylindrical lens surface of the cylindrical lens 54 is set so that the principal rays of the illumination beam EL1 passing through the illumination area IR are directed to the intersection point Q2 on the XZ plane. In this way, the principal rays of the projection light beam EL2 reflected in the illumination area IR become parallel (telecentric) to the straight line passing through the first axis AX1, the point Q1, and the intersection Q2 in the XZ plane. Of course, since the curvature of the surface P1 of the mask M in the Y direction can be regarded as infinite, the principal rays of the projection light beam EL2 are also telecentric in the Y direction.

Next, a plurality of projection areas PA1 to PA6 projected and exposed by the projection optical system PL will be described. As shown in FIG. 3, the plurality of projection areas PA1 to PA6 on the substrate P are arranged corresponding to the plurality of illumination areas IR1 to IR6 on the mask M. That is, the plurality of projection areas PA1 to PA6 on the substrate P are arranged with the first projection area PA1, the third projection area PA3, and the fifth projection area PA5 on the substrate P on the upstream side in the conveying direction with the center plane CL interposed therebetween. A second projection area PA2, a fourth projection area PA4, and a sixth projection area PA6 are arranged on the substrate P on the downstream side in the conveying direction. Each of the projection areas PA1 to PA6 has an elongated trapezoidal area extending in the short side and the long side in the width direction (Y direction) of the substrate P. At this time, each of the trapezoidal projection areas PA1 to PA6 is an area where the short side is located on the side of the center plane CL and the long side is located on the outside. The first projection area PA1, the third projection area PA3, and the fifth projection area PA5 are arranged at predetermined intervals in the width direction. In addition, the second projection area PA2, the fourth projection area PA4, and the sixth projection area PA6 are also arranged at predetermined intervals 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. The projection areas PA1 to PA6, similar to the illumination areas IR1 to IR6, are arranged in such a way that the triangles of the hypotenuses of adjacent trapezoidal projection areas PA overlap (overlap) when viewed from the conveying direction of the substrate P. At this time, the projection area PA has substantially the same shape as the exposure amount in the overlapping area of the adjacent projection area PA and the exposure amount in the non-overlapping area. The first to sixth projection areas PA1 to PA6 are arranged to cover the full width of the exposure area A7 exposed to the substrate P in the Y direction.

Here, in Figure 2, when viewed in the XZ plane, the perimeter from the center point of the odd number of illumination areas IR1 (and IR3, IR5) to the center point of the even number of illumination areas IR2 (and IR4, IR6) on the mask M The distance is set from the center point of the odd number of projection areas PA1 (and PA3, PA5) on the substrate P along the support surface P2 of the substrate support cylinder 25 to the center point of the even number of projection areas PA2 (and PA4, PA6) The perimeters are substantially equal. The reason is that the projection magnification of each of the projection optical systems PL1 to PL6 is equal to (×1).

The projection optical system PL is provided in plural (for example, six in the first embodiment) corresponding to the plural projection areas PA1 to PA6. The plurality of projection light beams EL2 reflected from the plurality of illumination areas IR1 to IR6 are respectively incident on the plurality of projection optical systems (divided projection optical systems) PL1 to PL6. The projection optical systems PL1 to PL6 guide the projection light beams EL2 reflected by the mask M to the projection areas 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 will come from the second to sixth Each of the projection light beams EL2 of the illumination areas IR2 to IR6 is guided to the second to sixth projection areas PA2 to PA6. The plurality of projection optical systems PL1 to PL6 are interposed with the center plane CL, and the first projection optical system PL1 and the third projection optical system PL1 and the third are arranged on the side where the first, third, and fifth projection areas PA1, PA3, and PA5 are arranged (the left side of FIG. 2) The projection optical system PL3 and the fifth projection optical system PL5. 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, a plurality of projection optical systems PL1 to PL6 are arranged with the center plane CL interposed therebetween, and the second projection optical system PL2 is arranged on the side where the second, fourth, and sixth projection areas PA2, PA4, PA6 are arranged (the right side of FIG. 2) The fourth projection optical system PL4 and the sixth projection optical system PL6. 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 in the axial direction between the first projection optical system PL1 and the third projection optical system PL3. Similarly, the third projection optical system PL3, the fourth projection optical system PL4, and the fifth projection optical system PL5 are arranged in the axial direction between the second projection optical system PL2 and the fourth projection optical system PL4, and the third projection optical system Between PL3 and the fifth projection optical system PL5, and between the fourth projection optical system PL4 and the sixth projection optical system PL6. In addition, the first projection optical system PL1, the third projection optical system PL3, and the fifth projection optical system PL5, the second projection optical system PL2, the fourth projection optical system PL4, and the sixth projection optical system PL6 are symmetrical when viewed from the Y direction. Configuration.

Next, the detailed configuration of each projection optical system PL1 to PL6 will be described with reference to FIG. 4. In addition, since each of the projection optical systems PL1 to PL6 has the same configuration, the first projection optical system PL1 (hereinafter, simply referred to as the 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 onto the projection area PA on the substrate P. The projection optical system PL includes the quarter wave plate 41, the polarization beam splitter PBS, and the projection optical module PLM in this order from the incident side of the projection light beam EL2 from the mask M.

The 1/4 wave plate 41 and the polarizing beam splitter PBS system are used together with the illumination optical system IL. In other words, the illumination optical system IL and the projection optical system PL share a quarter wave plate 41 and a polarization beam splitter PBS.

The projection light beam EL2 reflected in the illumination area IR is converted from circularly polarized light to linearly polarized light (P polarized light) by the quarter wave plate 41, and then penetrates the polarizing beam splitter PBS to become a telecentric imaging light beam and enter the projection optical system PL ( Projection optical module (PLM).

The projection optical module PLM and the illumination optical module ILM are arranged correspondingly. 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 on the substrate P The first projection area PA1. Similarly, the projection optical modules PLM of the second to sixth projection optical systems PL2 to PL6 will be illuminated by the second to sixth illumination regions IR2 by the illumination optical modules ILM of the second to sixth illumination optical systems IL2 to IL6 The image of the mask pattern of ~IR6 is projected on the second to sixth projection areas PA2 to PA6 on the substrate P.

As shown in FIG. 4, the projection optical module PLM is provided with a first optical system 61 that forms an image of the mask pattern of the illumination area IR on the intermediate image plane P7, and at least a part of the intermediate image formed by the first optical system 61 The second optical system 62 that reimages the projection area PA of the substrate P and the projection field diaphragm 63 that is arranged on the intermediate image plane P7 where the intermediate image is formed. In addition, the projection optical module PLM includes a focus correction optical member 64, an image shift optical member 65, an optical member 66 for magnification correction, a rotation correction mechanism 67, and a polarization adjustment mechanism 68.

The first optical system 61 and the second optical system 62 are, for example, a telecentric catadioptric optical system in which a Dyson system is deformed. 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 deflection member 70, a first lens group 71 and a first concave mirror 72. The first deflecting member 70 is a triangular shape having a first reflecting surface P3 and a second reflecting surface P4. The first reflection surface P3 reflects the projection light beam EL2 from the polarization beam splitter PBS, and causes the reflected projection light beam EL2 to pass through the first lens group 71 and enter the first concave mirror 72. The second reflection surface P4 is a surface that causes the projection light beam EL2 reflected by the first concave mirror 72 to pass through the first lens group 71 and is incident, and reflects the incident projection light beam EL2 toward the projection field diaphragm 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 arranged on a pupil surface where a plurality of point light sources generated by the fly-eye lens 52 pass through the illuminating field diaphragm 55 from the fly-eye lens 52 to the various lenses of the first concave mirror 72 to form an image.

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

The projection field diaphragm 63 has an opening that defines the shape of the projection area PA. That is, the shape of the opening of the projection field diaphragm 63 defines the shape of the projection area PA. Therefore, when the opening shape of the illumination field diaphragm 55 in the illumination optical system IL shown in FIG. 4 can be similar to the shape (trapezoid) of the projection area PA, the projection field diaphragm 63 can be omitted. In addition, when the aperture shape of the illumination field diaphragm 55 is a rectangle including the projection area PA, it is necessary to use the projection field diaphragm 63 to define the trapezoidal projection area PA.

The second optical system 62 has the same configuration as the first optical system 61, and is arranged symmetrically with the first optical system 61 across 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 deflection member 80, a second lens group 81, and a second concave mirror 82. The second deflection member 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 diaphragm 63, and causes the reflected projection light beam EL2 to pass through the second lens group 81 and enter the second concave mirror 82. The fourth reflection surface P6 is a surface that causes the projection light beam EL2 reflected by the second concave mirror 82 to pass through the second lens group 81 to be incident, and to reflect 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 a pupil surface where a plurality of point light source images formed on the first concave mirror 72 pass through the projection field diaphragm 63 from the first concave mirror 72 to the various lenses of the second concave mirror 82 to be formed.

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

The focus correction optical member 64 is arranged between the first deflection member 70 and the projection field diaphragm 63. The focus correction optical member 64 adjusts the focus state of the mask pattern image projected on the substrate P. The focus correction optical member 64 is, for example, by inverting two wedge-shaped ridges (inverted in the X direction in FIG. 4) to form a transparent parallel plate as a whole. If this pair of slabs slide down to the slope direction without changing the distance between the facing surfaces, the thickness of the parallel plates can be changed. Accordingly, it is possible to fine-tune the effective optical path length of the first optical system 61, and fine-tune the focus state of the mask pattern image formed on the intermediate image plane P7 and the projection area PA.

The image shift optical member 65 is arranged between the first deflecting member 70 and the projection field diaphragm 63. The optical member 65 for image shift can adjust the image of the mask pattern projected on the substrate P to move slightly within the image plane. The image shift optical member 65 is composed of transparent parallel plate glass that can be tilted in the XZ plane in FIG. 4 and a transparent parallel plate glass that can be tilted in the YZ plane in FIG. 4. By adjusting the inclination of the two parallel plate glasses, the image of the mask pattern formed on the intermediate image plane P7 and the projection area PA can be slightly shifted in the X direction and the Y direction.

The optical member 66 for magnification correction is arranged between the second deflection member 70 and the substrate P. The optical member 66 for magnification correction is composed of, for example, three concave lenses, convex lenses, and concave lenses that are coaxially arranged at predetermined intervals, the front and rear concave lenses are fixed, and the convex lens in between is movable in the direction of the optical axis (primary ray). Accordingly, the image of the mask pattern formed in the projection area PA can be slightly enlarged or reduced isotropically while maintaining the telecentric imaging state. In addition, the optical axis of the three lens groups constituting the optical member 66 for magnification correction is inclined in the XZ plane so as to be parallel to the chief ray of the projection light beam EL2.

The rotation correction mechanism 67 is, for example, one that slightly rotates the first deflection member 70 about an axis perpendicular to the second optical axis BX2 and parallel to the Z axis by an actuator (not shown). The rotation correcting mechanism 67 rotates the first deflection member 70 to slightly rotate the image of the mask pattern formed on the intermediate image plane P7 in the intermediate image plane P7.

The polarization adjustment mechanism 68 is configured to adjust the polarization direction by rotating the quarter-wave plate 41 around an axis orthogonal to the plate surface by an actuator (not shown). The polarization adjustment mechanism 68 can finely adjust the illuminance of the projection light beam EL2 projected on the projection area PA by rotating the quarter wave plate 41.

In the projection optical system PL constructed in this way, the principal rays of the projection light beam EL2 from the mask M are emitted from the surface P1 of the mask M in the illumination area IR in a telecentric state, and pass through the quarter wave plate 41 and polarized light. The beam splitter PBS is incident on the first optical system 61. The projection light beam EL2 incident on the first optical system 61 is reflected on the first reflecting surface (plane mirror) P3 of the first deflecting member 70 of the first optical system 61, and is reflected on the first concave mirror 72 by 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, is reflected on the second reflection surface (plane mirror) P4 of the first deflection member 70, and passes through the focus correction optical member 64 and the image shift optical member 65 And it enters the projection field diaphragm 63. The projection light beam EL2 passing through the projection field diaphragm 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 by 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 on the fourth reflection surface (plane mirror) P6 of the second deflection member 80, and enters the magnification correction optical member 66. The projection light beam EL2 emitted from the optical member 66 for magnification correction enters the projection area PA on the substrate P, and the image of the mask pattern appearing in the illumination area IR is projected on the projection area PA at the same magnification (×1).

＜Relationship between the projection image surface of the mask pattern and the exposure surface of the substrate＞ Next, the relationship between the projection image surface of the pattern of the mask of the exposure device U3 of the first embodiment and the exposure surface of the substrate will be described with reference to FIGS. 6A and 6B. 6A is an explanatory diagram showing the relationship between the projected image surface of the pattern of the photomask and the exposure surface of the substrate. Fig. 6B is an explanatory diagram schematically showing the change in the focus position (defocus amount) of the pattern image projected in the projection area.

The exposure device U3 uses the projection optical system PL to image the projection light beam EL2 to form the projection image surface Sm of the pattern of the mask M. The projection image surface Sm is the position where the pattern of the mask M is imaged, and is the position of the best focus. Here, the mask M is arranged with a curved surface (curved in the ZX plane) with a radius of curvature Rm as described above. Therefore, the projection image surface Sm is also a curved surface with a radius of curvature Rm. In addition, in the exposure device U3, the surface of the substrate P is the exposure surface Sp. Here, the so-called exposure surface Sp is the surface of the substrate P. The substrate P is held by the cylindrical substrate support cylinder 25 as described above. Thereby, the exposure surface Sp becomes a curved surface (curve in the ZX plane) of the radius of curvature Rm. In addition, the projection image surface Sm and the exposure surface Sp are axes whose directions orthogonal to the scanning exposure direction are curved surfaces.

Therefore, as shown in FIG. 6A, the projection image surface Sm and the exposure surface Sp are curved surfaces with respect to the scanning exposure direction (the circumferential direction of the outer circumferential surface of the substrate support cylinder 25). Therefore, the projection image surface Sm is curved at the center position and the center position of the exposure width A in the scanning exposure direction of the projection area PA in the principal ray direction of the projection light beam EL2 with the maximum ΔFm surface position difference. The exposure surface Sp is The projection area PA is bent at the center position and the center position of the exposure width A in the scanning exposure direction along with the plane position difference of the maximum ΔFp in the principal ray direction of the projection light beam EL2. Here, the exposure device U3, as shown in FIG. 6A, uses the actual exposure surface Spa relative to the projection image surface Sm and the exposure surface Sp (the surface of the substrate P) at the time of actual exposure. The first axis AX1 of the mask M The second axis AX2 of the substrate support cylinder 25 is pivotally supported by the exposure apparatus body.

The actual exposure surface Spa intersects at two positions FC1, FC2 that are different from the projection image surface Sm in the scanning exposure direction. In addition, the exposure device U3 can fine-tune the distance between the mask M and the substrate P by adjusting the position of each optical member of the projection optical system PL, or by either of the mask holding mechanism 11 and the substrate supporting mechanism 12, or by adjusting the focus correction optics The member 64 changes the position in the normal direction (focus adjustment direction) of the actual exposure surface Spa relative to the projection image surface Sm.

The projection image plane Sm and the actual exposure plane Spa are set to intersect each of two different positions FC1, FC2 within the exposure width A of the scanning exposure direction of the projection area PA. Therefore, at each of the positions FC1 and FC2 within the exposure width A, the pattern image of the mask M is projected and exposed on the surface of the substrate P in the best focus state. In addition, the area between the position FC1 and the position FC2 within the exposure width A becomes the best focus surface (projection image surface Sm) of the pattern image to be projected, which is located behind the actual exposure surface Spa, and is in a higher position than FC1 The area further outside between FC2 and the position FC2 becomes the best focus surface (projection image surface Sm) of the projected pattern image and is in the focus state before the actual exposure surface Spa.

That is, when the surface of the substrate P goes from the end As on one side of the exposure width A to the end Ae on the other side along the actual exposure surface Spa, the pattern image on the substrate P is at the end As at the beginning of the exposure The position is exposed with a predetermined amount of defocus, and thereafter, the amount of defocus decreases with time, and the position FC1 is exposed with the best focus (the amount of defocus is zero). After passing the best focus state at the position FC1, the defocus amount increases in the opposite direction, and becomes the maximum defocus amount at the center position FC3 of the exposure width A. Taking the center position FC3 of the exposure width A as the turning point, the defocus amount is reduced thereafter, and the pattern image is again exposed on the substrate P in the best focus state at the position FC2. After passing the best focus state at position FC2, the defocus amount increases again, and at the other end Ae, the exposure of the pattern image ends. As described above, the area between the position FC1 and the position FC2 and the area outside between the position FC1 and the position FC2 have different directions of defocusing, that is, the coincidence system of the defocusing.

As described above, during the period when the substrate P moves at a certain peripheral speed from the end As of the exposure width A of the projection area PA to the end Ae, each point in the pattern image projected on the substrate P is as shown in FIG. 6B Show, start exposure in the front focus state (position As), in the order of best focus state (position FC1), back focus state (position FC3), best focus state (position FC2), front focus state (position Ae) Exposure to the substrate P while continuously changing. The zero of the focus position (or defocus amount) of the vertical axis in FIG. 6B is the best focus state where the difference (Sm-Spa) between the position of the projection image surface Sm and the position of the actual exposure surface Spa is zero. In addition, although the horizontal axis of FIG. 6B shows the linear position of the exposure width A, it may also be the position of the outer peripheral surface of the substrate support cylinder 25 in the circumferential direction.

The amount of defocus in the focus state (positive direction) before the end As and Ae of the exposure width A, and the amount of defocus in the focus state (negative direction) after the center position FC3 can be based on the imaging performance of the projection optical system PL (resolution, Depth of focus), the exposure width A of the projection area PA, the minimum size of the mask pattern to be projected, the radius of curvature Rm of the surface P1 of the mask M (projection image surface Sm), the outer peripheral surface of the substrate support cylinder 25 (substrate P The radius of curvature Rp of the upper exposure surface Spa) determines the better range. Specific examples are described later, but as described above, by continuously changing the focus state during scanning exposure covering the exposure width A, it is possible to enlarge the individual thin lines or discrete contact holes (through holes) in the mask pattern. ) And the depth of focus on the appearance of isolated patterns.

Furthermore, in this embodiment, by making the surface P1 of the mask M and the surface of the substrate P into a cylindrical shape, it is possible to project the mask pattern on the projection image surface of the scanning exposure direction on the side of the substrate P and the exposed substrate. The exposed surface gives a poor cylindrical shape. Therefore, the exposure device U3 can continuously change the focus state corresponding to the position of the scanning exposure direction in the projection area PA only through the rotational movement of the mask M and the substrate support cylinder 25, thereby suppressing the substantially focused image Contrast changes. In addition, in this embodiment, in the projection area PA, the exposure width A is set to achieve the best focus in two positions of the scanning exposure direction. Therefore, the average defocus amount within the exposure width A can be reduced and the exposure can be increased. Width A. Thereby, when the illuminance of the projection beam EL2 is reduced, or when the scanning speed of the mask M or the substrate P in the scanning exposure direction is increased, an appropriate exposure amount can be ensured, thereby processing the substrate with high production efficiency. In addition, since the average defocus amount can be reduced relative to the exposure width, the quality can also be maintained.

In this embodiment, the focal position is differently exposed corresponding to the coordinate position (circumferential position) of the exposure width A. As a result, the accumulation of the pattern images projected on the substrate P with different focus states in the exposure width A The image becomes the final image intensity distribution formed on the exposed surface of the substrate P. Although the accumulated image will be explained here, in order to make the explanation simple, first, the concept is explained with the point image intensity distribution. Roughly speaking, the point image intensity distribution is its contrast and correlation. The point image intensity distribution I(z) at the position after defocusing z toward the optical axis (direction of focus change) is the following formula. Here, λ is the wavelength of the illumination beam EL1, NA is the numerical aperture on the substrate side of the projection optical system PL, and I ₀ is the intensity distribution at the ideal best focus position, and ΔDz = (π /2/λ)×NA ² ×z, the point image intensity distribution I(z) becomes I(z)=[siN(ΔDz)/(ΔDz)] ² ×I ₀ .

If the above point image intensity distribution I(ｚ) is used, the cumulative value (or average value) of the exposure width A can be obtained, and then the horizontal axis is taken at the actual center position (the center position FC3 in Figure 6A) The defocus amount can be simulated to obtain the intensity distribution of each defocus amount. Accordingly, by adjusting the focus state (the positional relationship between the projection image surface Sm and the actual exposure surface Spa) with the exposure device U3, the intensity distribution (image contrast) of the pattern image obtained during exposure can be adjusted to the best state.

Moreover, in general, the resolution R and the focal depth DOF of the projection optical system PL are expressed by the following formula. R=k1・λ/NA (0＜k1≦1) DOF=k2・λ/NA ² (0＜k2≦1) Here, although k1 and k2 are affected by exposure conditions or photosensitive materials (photoresist, etc.), Or the coefficient may be changed by the development process or the film forming process after exposure, but the k1 factor of the resolution R is about 0.4≦k1≦0.8, and the k2 factor of the focal depth DOF can be expressed as about k2≒1.

Based on the definition of the focal depth DOF of the projection optical system PL, in this embodiment, it is preferable to first adjust it to approximately satisfy the following relational expression. [Formula 1]

[式3]

Here, ΔRm and ΔRp are based on the radius of curvature Rm of the projection image surface Sm (surface P1 of the mask M), the radius of curvature Rp of the surface of the substrate P (the actual exposure surface Spa), and the exposure width A, respectively, as follows Find out. [Equation 2]

[Equation 3]

It is clear from this formula that ΔRm and ΔRp respectively represent ΔFm and ΔFp shown in Fig. 6A. In addition, the aforementioned relational expression 1 preferably further satisfies DOF<(ΔRm+ΔRp). In the exposure apparatus U3 of this embodiment, although the exposure width A, the radius of curvature Rm, and Rp are determined by satisfying the above-mentioned relational expression 1, the display panel formed on the substrate P can be maintained by satisfying the above-mentioned relational expression 1 The quality of various patterns used (line width accuracy, position accuracy, overlap accuracy, etc.), while improving productivity. Regarding this point, the second embodiment will be described in detail.

Moreover, in this embodiment, the variation range of the defocus amount within the exposure width A, that is, the defocus amount at the end As and Ae shown in FIG. 6B in the positive direction, and the center position FC3 in the exposure width A When the difference in the amount of defocus in the negative direction is set to ΔDA, from the perspective of the relationship with the focal depth DOF of the projection optical system PL, it is preferably set to satisfy the relationship of 0.5≦(ΔDA/DOF)≦3, and more preferably To satisfy 1≦(ΔDA/DOF). By setting the exposure device U3 to satisfy this relationship, the quality (line width accuracy, position accuracy, overlap accuracy, etc.) of various patterns for the display panel formed on the substrate P can be maintained, and productivity can be improved. Regarding this point, the second embodiment will be described in detail.

In addition, as shown in FIG. 6B of this embodiment, the exposure device U3 is preferably set to expose the projection area PA as the difference between the projection image surface Sm of the pattern of the mask M and the actual exposure surface Spa of the substrate P in the scanning exposure direction The center position FC3 of the width A changes into line symmetry as an axis (left-right symmetry in FIG. 6B).

In addition, in this embodiment, as shown in FIG. 6B, the defocus amount within the exposure width A of the projection area PA may be positive in the interval from the end As to the position FC1 and the interval from the position FC2 to the end Ae. The integrated value of the defocus in the positive direction (absolute value) is compared with the integrated value of the defocus in the negative direction (absolute value) in the interval from position FC1 to position FC2 where the defocus amount is negative. The positional relationship between the projection image surface Sm and the actual exposure surface Spa is set in a substantially equal manner.

In the exposure device U3 of this embodiment, a plurality of projection optical modules PLM are arranged in at least two rows in the scanning exposure direction, in the Y direction orthogonal to the scanning exposure direction, so that the projection area of the adjacent projection optical modules PLM The ends (triangular parts) of the PA overlap each other to expose the pattern of the mask M in the Y direction. Thereby, it is possible to suppress the occurrence of band unevenness due to the contrast of the pattern image or the difference in the exposure amount of the junction (overlapping area) between two adjacent projection areas PA in the Y direction. In this embodiment, in addition, because the scanning exposure direction in the projection area PA on the actual exposure surface Spa (the surface of the substrate P) can form two best focus positions (position FC1, position FC2) The method sets the positional relationship between the projected image surface Sm and the actual exposure surface Spa, so that the change in the image contrast caused by the dynamic defocusing caused by the slight change in the positional relationship between the projected image surface Sm and the actual exposure surface Spa in the scanning exposure can be reduced. Therefore, it is also possible to reduce the difference in image contrast generated in the overlapping area between adjacent projection areas PA, and it is possible to manufacture a high-quality flexible display panel with inconspicuous joints.

As shown in this embodiment, when the projection areas PA of a plurality of projection optical modules PLM are arranged in the Y direction orthogonal to the scanning exposure direction (X direction), the width of each projection area PA in the scanning exposure direction The integrated value obtained by integrating the illuminance (intensity of exposure light) on the substrate P is preferably substantially constant at any position in the Y direction orthogonal to the scanning exposure direction. In addition, the part where the ends of two adjacent projection areas PA in the Y direction partially overlap (the overlapping area of triangles) is also set as the sum of the accumulated value in one triangular area and the accumulated value in the other triangular area. The cumulative value of non-overlapping areas is the same. With this, it is possible to suppress changes in the exposure amount in the direction orthogonal to the scanning exposure direction.

In addition, the exposure device U3, by making the projection image surface Sm and the exposure surface Sp (the actual exposure surface Spa) into a cylindrical surface, as shown in this embodiment, even if a plurality of projection optical modules PLM are arranged in the scanning exposure direction (The two rows of odd and even rows are arranged). Since the relationship between the projection image surface Sm and the exposure surface Sp (the actual exposure surface Spa) in each projection optical module PLM is the same, the relationship can be adjusted together. Like the usual multi-lens projection exposure device, when the projection image surface and the exposure surface are flat, for example, in the projection area of an odd number of projection optical modules, the exposure surface (the surface of the flat substrate) ) Tilting relative to the projection image plane, the projection area of an even number of projection optical modules will have a large defocus that is difficult to tolerate. In contrast, as shown in this embodiment, by making the projection image surface Sm and the exposure surface Sp (the actual exposure surface Spa) into cylindrical surfaces, two rows of projection optical modules PLM arranged in the scanning exposure direction are projected on each The focus adjustment of the area PA can pass through the distance between the first axis AX1 of the rotation center of the cylindrical mask M and the first axis AX1 of the rotation center of the substrate support cylinder 25 in the Z direction, or each projection optical module PLM The internal magnification correction is simply realized by adjusting the optical member 66. Thereby, it is possible to suppress changes in image contrast relative to defocus with a simple device configuration. Since the change in image contrast can be suppressed while increasing the exposure width of the scanning exposure area, the production efficiency is also improved.

[Second Embodiment] Next, the exposure apparatus U3a of the second embodiment will be described with reference to FIG. 7. In addition, in order to avoid repetitive descriptions, the description will be given for the parts that are different from the first embodiment, and the same components as those of the first embodiment are given the same reference numerals as those of the first embodiment. Fig. 7 is a diagram showing the overall configuration of the exposure apparatus (substrate processing apparatus) of the second embodiment. Although the exposure apparatus U3 of the first embodiment is configured to hold the substrate P passing through the projection area by the cylindrical substrate support cylinder 25, the exposure apparatus U3a of the second embodiment holds the substrate P so as to support the substrate P The structure of the substrate support mechanism 12a which is planar and movable.

In the exposure apparatus U3a of the second embodiment, the substrate support mechanism 12a includes a substrate stage 102 that holds the substrate P in a planar shape, and a moving device that scans and moves the substrate stage 102 in the X direction in a plane orthogonal to the center plane CL (The illustration is omitted). Therefore, the substrate P can be a flexible sheet (PET, PEN, etc. resin mold, extremely thin curved peeling surface, thin metal foil, etc.), and can also be a glass substrate with a blade that is hardly curved.

Since the supporting surface P2 of the substrate P in FIG. 7 is a plane substantially parallel to the XY plane (radius of curvature ∞), it reflects from the mask M, passes through the projection optical module PLM, and is projected onto the substrate P. The projection beam EL2 and the XY plane Into vertical.

Also, in the second embodiment, similar to the previous FIG. 2, when viewed in the XZ plane, from the center point of the illumination area IR1 (and IR3, IR5) on the cylindrical mask M to the illumination area IR2 ( And IR4, IR6) and the center point of the projection area PA1 (and PA3, PA5) on the substrate P along the support surface P2 to the center point of the second projection area PA2 (and PA4, PA6) The linear distance in the X direction is set to be substantially equal.

The exposure device U3a in FIG. 7 is the same. The lower control device 16 controls the moving device of the substrate support mechanism 12 (linear motor for scanning exposure or actuator for micro-movement, etc.) to synchronize with the rotation of the mask holding cylinder 21 The substrate stage 102 is driven ground.

Next, the relationship between the projected image surface of the mask pattern and the exposure surface of the substrate in the exposure apparatus U3a of the second embodiment will be described with reference to FIG. 8. FIG. 8 is an explanatory diagram showing the relationship between the projection image surface of the pattern of the photomask and the exposure surface of the substrate.

The exposure device U3a forms the projection image surface Sm1 of the pattern of the mask M by imaging the projection light beam EL2 by the projection optical system PL. The projection image surface Sm1 is a surface that images the cylindrical mask pattern surface of the mask M in the best focus state, and is a cylindrical surface. Here, the illumination area IR on the mask M is a part of the curved surface with the radius of curvature Rm1 (in the XZ plane) as described above, so the projection image surface Sm1 is also the curved surface with the radius of curvature Rm1 (in the XZ plane) Is part of the arc). In addition, the planar surface of the substrate P on which the image of the mask pattern is projected is the exposure surface Sp1 (radius of curvature ∞). Therefore, as shown in FIG. 8, the projection image surface Sm1 (left side) of the odd-numbered projection area PA and the projection image surface Sm1 (right side) of the even-numbered projection area PA are both curved into a cylindrical shape in the scanning exposure direction (X direction), As shown in the previous FIG. 6A, within the exposure width A of the projection area PA in the scanning exposure direction, there is a difference between the focus positions at both ends and the focus position at the center of the exposure width A, that is, the plane position difference (focus Change width) ΔFm. Here, during scanning exposure, the surface of the substrate P is arranged on the actual exposure surface Spa1. Since the exposure surface Sp1 and the actual exposure surface Spa1 are flat surfaces, within the exposure width A of the projection area PA in the scanning exposure direction, the amount of change in the surface position in the Z direction is zero. The actual exposure surface Spa1 is set to intersect two different positions FC1 and FC2 separated in the scanning exposure direction on the projection image surface Sm1. That is, the exposure device U3 can adjust the magnification correction optical member 66 in the projection optical system PL, etc., or move either the mask holding mechanism 11 (first axis AX1) and the substrate support mechanism 102 in the Z direction. The relative positional relationship between the projection image surface Sm1 and the actual exposure surface Spa1 is set to a predetermined state.

Each of the two positions FC1 and FC2 is the position where the mask pattern image in the projection image plane Sm1 is exposed in the best focus state.

In this way, in the same way in the present embodiment, by rotating the cylindrical mask M, scanning exposure can be performed in which the focus state is continuously changed within a predetermined range within the exposure width A in the scanning exposure direction. In turn, it is possible to suppress changes in image contrast relative to the actual focus. As mentioned above, even if the exposure surface Sp1 (the actual exposure surface Spa1) is a flat surface, the projection image surface Sm1 can be made into a cylindrical surface curved in the scanning exposure direction, so that it can be obtained without tilting the substrate P The appearance enlarges the effect of the focal depth of the mask pattern image exposed on the substrate P, and can suppress the change of the image contrast. This effect can also be achieved in the case of projecting and exposing the pattern image from a normal flat mask on the surface (exposure surface) of the substrate supported in a cylindrical shape.

求出。因此，以此式2為基礎，試著進行圖7之曝光裝置U3a中之投影狀態或成像特性等各種模擬後，可得到如圖9～圖17之結果。In addition, in the case of the present embodiment, the surface position difference (focus change width) ΔFm shown in FIG. 8 is the same as the ΔRm of the previous equation 2, so it can be expressed as [Equation 4]

Find out. Therefore, based on Equation 2, after trying various simulations such as the projection state or imaging characteristics of the exposure device U3a in Fig. 7, the results shown in Figs. 9-17 can be obtained.

In addition, in this simulation, if the radius Rm of the surface P1 (projection image surface Sm1) of the cylindrical mask M is set to 250mm (diameter ψ500mm), the wavelength λ of the illumination beam EL1 for exposure is set to the i line (365nm), the projection optical system PL is set as an ideal projection system with a numerical aperture NA equal to 0.0875. The exposure surface Sp1 (the actual exposure surface Spa1) is a plane with a radius of curvature of ∞, which depends on the k2 factor of the focal depth of the process DOF Set to 1.0, the focal depth DOF of this projection optical system PL is approximately 48 μm in width based on λ/NA ² (the range of approximately ±24 μm relative to the best focus plane). In addition, in the following simulations, for convenience of explanation, there are occasions where the focal depth DOF is set to a width of 40 μm (the range of approximately ±20 μm relative to the best focus surface).

Furthermore, FIG. 9 shows the defocus characteristic Cm of the projection optical system PL within the exposure width A, the horizontal axis represents the coordinates in the X direction with the center position of the exposure width A as the origin, and the vertical axis represents the best focus position It is the defocus amount of the projection image surface Sm1 at the origin (zero point). The graph in Fig. 9 is also a graph obtained by drawing the surface position difference ΔRm obtained by setting the exposure width A to 20mm in the previous formula 2 and changing the coordinate position of the width A from -10mm to +10mm. As shown in the graph of FIG. 9, the surface P1 (projection image surface Sm1) of the mask M is curved in a cylindrical shape in the scanning exposure direction, and the defocus characteristic Cm within the exposure width A changes in an arc shape.

Figure 10 is a graph that simulates how the point image intensity changes with respect to the DOF width of the focal depth in the defocus characteristic Cm shown in Figure 9. The horizontal axis represents the surface accuracy of the surface of the substrate P or the mask pattern surface. Error, the amount of blur in the focus direction (the offset of the surface of the substrate P relative to the defocus characteristic Cm in the focus direction) caused by the aberration in the image plane direction of the projection optical system PL, the vertical axis represents the value of the point image intensity. In Fig. 10, the point image intensity at the center (origin) of the exposure width A is set as the point image intensity distribution calculated when the focal depth DOF is 0×DOF before the defocus characteristic Cm in Fig. 9 1.0 and standardized. FIG. 11 is a graph simulating an example of the relationship between the change amount of the defocus characteristic Cm of FIG. 9 and the intensity difference (the amount of intensity change) in an arc-shaped change within the exposure width A. Figure 12 shows the defocus characteristics Cm and the line and space (L/S, L&S) of the arc-shaped change in the exposure width A when the optimal focus is set by the simulation device and when the defocus generated by the device is set to 24μm An example of the relationship between pattern contrast and change. FIG. 13 is also a graph simulating another example of the relationship between the defocus characteristic Cm that changes in an arc shape in the exposure width A and the contrast ratio change of the L/S pattern. 14 is a graph simulating an example of the relationship between the defocus characteristic Cm of the arc-shaped change in the exposure width A, the CD (critical dimension) value and the slice level of the L/S pattern. FIG. 15 is a graph simulating an example of the relationship between the defocus characteristic Cm and the contrast change of the isolated line (ISO pattern) in the arc-shaped change in the exposure width A. FIG. 16 is a graph simulating another example of the relationship between the defocus characteristic Cm of the arc-shaped change in the exposure width A and the change of the contrast ratio of the isolated line. Fig. 17 is a graph simulating an example of the relationship between the defocus characteristic Cm of the arc-shaped change in the exposure width A, the CD value of the isolated line and the cut level.

First, under the above conditions, the point image intensity distribution I(z) of the defocus generated when the defocus characteristic Cm that changes in an arc shape within the exposure width A is divided by the focal depth DOF unit is shown in Fig. 10 Show out. The point image intensity distribution is obtained by the previously explained formula I(z)=[sin(ΔDz)/(ΔDz)] ² ×I ₀ , ΔDz=(π/2/λ)×NA ² ×z.

Secondly, for the assumption that the average of the defocus amount is adjusted to achieve the best focus, the point image intensity distribution when the substrate is adjusted in an arc-shaped manner within the exposure width A, the defocus width is set to various values such as 0, 1×DOF, 2 ×DOF, 3×DOF, 4×DOF are calculated. In addition, when the defocus width varies in an arc shape within the exposure width A, the point image intensity distribution when the defocus is defocused from the position is calculated based on the defocus amount and the slit width. In this way, the relationship between the point image intensity distribution and the defocus when the defocus width varies in an arc shape in each exposure width A that is uniquely determined by the calculated exposure width A is integrated. Specifically, it is aimed at setting the defocus width of the exposure device U3a in an arc shape within the exposure width to 0, 0.5×DOF, 1×DOF, 1.5×DOF, 2×DOF, 2.5×DOF, 3×DOF , 3.5×DOF, 4×DOF, calculate the relationship between the point image intensity distribution and the assumed focus error and defocus during exposure.

Secondly, set various values such as 0, 1×DOF, for the defocus characteristic Cm that assumes that the average of the defocus amount is adjusted to achieve the best focus when the point image intensity distribution changes in an arc shape within the exposure width A. 2×DOF, 3×DOF, 4×DOF are calculated. In addition, when the defocus characteristic Cm that changes in an arc shape within the exposure width A is various, the point image intensity distribution when the defocus is defocused from the position is calculated based on the defocus amount and the slit width. In this way, the relationship between the point image intensity distribution and the defocus when each defocus characteristic Cm that is uniquely determined by the calculated exposure width A is integrated. Specifically, the defocus characteristic Cm shown in Fig. 9 set in simulation as the exposure device U3a is set to 0×DOF, 0.5×DOF, 1×DOF, 1.5×DOF, 2×DOF, 2.5×DOF , 3×DOF, 3.5×DOF, 4×DOF, calculate the point image intensity distribution and the assumed focus error during exposure (from the set projection image surface Sm1 and the surface of the substrate P should be set position relationship的Offset) relationship. This is equivalent to the chart in Figure 10.

In FIG. 10, the horizontal axis is the defocus amount [μm], and the vertical axis is the normalized point image intensity value. In addition, because the exposure device U3a rotates the cylindrical mask pattern surface, that is, the projection image surface Sm to project the projection light beam EL2 on the substrate P, the focus error assumed during exposure is performed twice. Variety. Therefore, the state of the point image on the positive side and the negative side of the defocus is slightly different. In this embodiment, the position where the defocus is at a point intensity of +40 μm and the point intensity at a position of -40 μm are symmetrical intensities as the best focus. As shown in the graph in Figure 10, as the amplitude due to rotation increases, that is, as the defocus width in the exposure area increases along the defocus characteristic Cm in Figure 9, the point image at the best focus The intensity becomes lower, and the change of the point image intensity when defocusing also becomes smaller.

Next, calculate the point image intensity change at each occasion where the arc-shaped defocus characteristic Cm changes within the exposure width A, that is, the difference between the maximum and minimum point image intensity, and then calculate the defocus within the exposure width A The characteristic Cm is the difference component of the point image intensity change at two points with different 0.5DOF. The calculation results are shown in Figure 11. The vertical axis of FIG. 11 represents the difference component of the two point image intensity changes, and the horizontal axis represents the object of the difference component when the defocus characteristic Cm is changed every 0.5 DOF. That is, in the horizontal axis of FIG. 11, for example, the leftmost point image intensity difference (approximately 0.02) is the difference between when the defocus characteristic Cm is changed by 0×DOF and when it is changed by 0.5×DOF. According to the simulation results in Fig. 11, the difference between the point image intensity changes when the defocus characteristic Cm has changed by 0.5×DOF amount is changed to the state where the defocus characteristic Cm has changed by 1×DOF amount, and the defocus characteristic Cm has changed 2.5 When the state of the ×DOF amount transitions to the state where the amount of 3 ×DOF has changed, the overall difference is large. That is, in the range of 0.5×DOF to 3×DOF, the change in point image intensity is more gentle than the change in defocus amount. Therefore, the defocus amount according to the defocus characteristic Cm is effective when it is set to an amplitude of 0.5 to 3 times the depth of focus DOF.

In addition, in the graph of FIG. 10, when the surface of the substrate P is coated with a photoresist as a photosensitive layer with a certain thickness, the value of the point image intensity of the image formed on the photoresist may vary depending on the resist used. However, according to experiments, when the k1 factor of the resolution is about 0.5, the point image intensity can be formed as an image as long as it is approximately 0.6 or more. Here, if the focus error estimated as the exposure device is set to the defocus width of the definition formula λ/NA ² of the focal depth DOF (in this embodiment, it is ±24μm), by setting the The amplitude of the defocus, that is, the defocus width, is set to 2.5×DOF, that is, the image of the mask pattern can be formed well with little change in image intensity.

Secondly, various calculations are performed when the mask pattern to be projected is set as the L/S (line and space) pattern. Hereinafter, the consideration object of defocus is set as the range of the focal depth definition formula, that is, ±24 μm in the present embodiment. The L/S (line and space) pattern is a pattern in which a plurality of linear patterns with a line width of 2.5 μm are arranged in a grid pattern at intervals of 2.5 μm in the line width direction. Furthermore, since the imaging state differs depending on the lighting conditions, in this embodiment, the lighting conditions of the lighting optical system IL, that is, the lighting numerical aperture σ is set to 0.7.

First, when the defocus characteristic Cm shown in Fig. 9 is changed into various situations, that is, 0×DOF, 0.5×DOF, 1×DOF, 1.5×DOF, 2×DOF, 2.5×DOF, 3×DOF, 3.5×DOF, 4×DOF, that is, when changing in 0.5DOF units, calculate the light intensity distribution of the L/S pattern image in the best focus state and the defocus state of DOF/2, that is, at +24μm Or -24μm to calculate the light intensity distribution of the L/S pattern in a defocused state.

Based on the calculation results, the changes in the contrast between the best focus state and the DOF/2 defocus state are calculated, and the graph after drawing this is shown in Figure 12. The horizontal axis in Fig. 12 represents the defocus width generated by the arc-shaped defocus characteristic Cm in the exposure width A, and the horizontal axis represents the contrast. The contrast change in the best focus state is set to 0μm (BestF), and The contrast change of the defocus state is set to ±24μmDef. In addition, according to the results shown in Fig. 12, the ratio of the contrast between the best focus state [0μm(BestF)] and the DOF/2 defocus state [±24μmDef], that is [0μm(BestF)]/[± The calculated result of 24μmDef] is shown in Fig. 13. In Fig. 13, the horizontal axis is the defocus width generated by the arc-shaped defocus characteristic Cm in the exposure width A, and the horizontal axis is the contrast.

In addition, calculate the CD (Critical Dimension) value [μm] and the cut level (light intensity of the image) in the defocus width generated by the arc-shaped defocus characteristic Cm in the exposure width A . In addition, the CD value is calculated when the defocus is ±24μm, and the cut level is calculated as the best focus. The calculation results are shown in Figure 14. The horizontal axis of FIG. 14 represents the defocus width on the defocus characteristic Cm of the arc-shaped change within the exposure width A. The left side of the vertical axis represents the CD value, and the right side represents the relative light intensity at the cut level.

As shown in Figure 14, in the case of the L/S pattern to be projected, relative to the change in the defocus amplitude in the exposure area, the change in line width (the change in CD value) is less, as shown in the previous figure 12. Great changes. However, as shown in Fig. 13, it can be seen that as the amplitude of defocus becomes larger, the ratio of the contrast in the best focus state to the contrast in the ±24μm defocus state approaches 1. As described above, in the scanning exposure method in which the exposure width A is set along the circumferential direction of the cylindrical projection image surface Sm1, the defocusing characteristic Cm that changes in an arc shape within the exposure width A is increased to generate the defocus The focus width can make the contrast ratio close to 1, and reduce the difference between the image contrast in the best focus state and the image contrast in the defocus state. With this, in the case of a cylindrical mask M (cylindrical projection image surface Sm1), it is possible to suppress the change of the contrast between the best focus and the defocus only by rotating motion Smaller, scanning exposure for suppressing the variation of the line width of the pattern to be exposed, while increasing the variation margin of the projection image surface Sm1 and the surface of the substrate P in the focusing direction (the diameter direction of the cylindrical surface).

Secondly, various calculations are performed when the pattern of the mask is set as an isolated line pattern. Hereinafter, the consideration object of defocus is set as the range of the focal depth definition formula, that is, ±24 μm in the present embodiment. The isolated line pattern is a linear pattern with a line width of 2.5μm. Furthermore, since the imaging state differs depending on the lighting conditions, the lighting numerical aperture σ as the lighting conditions is set to 0.7.

In the same way as the previous simulation of the L/S pattern, first, when changing the defocus characteristic Cm shown in Fig. 9 to various, that is, the same as the above for 0×DOF, 0.5×DOF, 1× DOF, 1.5×DOF, 2×DOF, 2.5×DOF, 3×DOF, 3.5×DOF, 4×DOF, that is, when changing in 0.5DOF units, calculate the light intensity distribution of the isolated line pattern image in the best focus state and The DOF/2 defocus state, that is, the light intensity distribution of the isolated line pattern in the defocused state is calculated at +24μm or -24μm. Based on the calculation result, the change characteristic of the image contrast with respect to the change of the defocus width of each 0.5 DOF as shown in FIG. 15 was obtained.

The horizontal axis of FIG. 15 represents the defocus width generated by the arc-shaped defocus characteristic Cm in the exposure width A, and the horizontal axis represents the contrast of the isolated line pattern image. Also, according to the results shown in Fig. 15, as in the previous Fig. 13, the ratio of the best focus state [0μm(BestF)] to the DOF/2 defocus state [±24μmDef], which is [0μm The calculated result of (BestF)]/[±24μmDef] is shown in Fig. 16. Figure 16, the horizontal axis is the defocus width generated by the arc-shaped defocus characteristic Cm in the exposure width A, and the horizontal axis is the contrast ratio.

In addition, calculate the CD (Critical Dimension) value [μm] and the cut level (light intensity of the image) in the defocus width generated by the arc-shaped defocus characteristic Cm in the exposure width A . In addition, the CD value is calculated when the defocus is ±24μm, and the cut level is calculated as the best focus. The calculation result is shown in Fig. 17. The horizontal axis of FIG. 17 represents the defocus width on the defocus characteristic Cm of the arc-shaped change within the exposure width A. The left side of the vertical axis represents the CD value, and the right side represents the relative light intensity at the cut level. As shown in Figure 17, when the pattern is an isolated line, the contrast change with respect to the change of the defocus amplitude in the exposure area is smaller than that of the L/S pattern. In contrast, it can be seen that when the pattern is an isolated line, the line width (CD value) changes greatly with respect to the change in the defocus amount.

Therefore, by setting the defocus width generated by the arc-shaped defocus characteristic Cm in the exposure width A to a larger 2.5×DOF or 3×DOF, even if the set focus position changes, it can be suppressed The line width of the pattern exposed on the substrate P changes. That is, even if the relative positional relationship between the preset projection image surface Sm1 and the surface of the substrate P in the focus direction changes due to various reasons during exposure, the line width change with respect to the focus change can be suppressed, and the compliance can be maintained well. The quality of the display panel or electronic components manufactured on the substrate P in sequence. In addition, it can be seen that the isolated line with a line width of 2.5μm at the time of the best focus and the cut-off level of 2.5μm will increase with the increase in the defocus width generated by the defocus characteristic Cm that changes in an arc shape within the exposure width A It becomes a larger value, and as a result, the change in line width becomes smaller with respect to defocus.

In addition, using the previous figures 14 and 17 to compare the difference in clipping level caused by the pattern difference, it can be seen that if the defocusing characteristic Cm that changes in an arc shape in the exposure width A is set to 2.25 ×DOF, compared with the L/S pattern and the isolated line pattern, the cut level (light intensity) is roughly the same. Therefore, by setting the defocus width due to the defocus characteristic Cm to the range of 2.25×DOF, a high-quality substrate can be manufactured even in the case of a mask pattern in which the L/S pattern and the isolated line pattern are mixed. Thereby, there is no need to consider the line width correction (OPC, line width offset) of the mask pattern that is necessary when the cut levels in the L/S pattern and the isolated line pattern are inconsistent, and the two can coexist. In addition, since there is no need to reproduce the mask for line width correction (OPC, line width offset) or to manufacture multiple masks for adjustment, the manufacturing steps and costs can be reduced. In addition, by changing the line width of a part of the mask pattern due to the line width setting offset, it is also possible to suppress the occurrence of problems such as narrowing the depth of focus in this part.

[Third Embodiment] Next, the exposure apparatus U3b of the third embodiment will be described with reference to FIG. 18. In order to avoid repetitive descriptions, only the differences from the second embodiment will be described, and the same components as in the second embodiment will be described with the same reference numerals as in the second embodiment. Fig. 18 is a diagram showing the overall configuration of an exposure apparatus (substrate processing apparatus) of the third embodiment. Although the exposure device U3 of the second embodiment is a reflection type mask that reflects the light of the mask into a projection beam, the exposure device U3b of the third embodiment uses a transmission type light that transmits the light through the mask into a projection beam. The composition of the hood.

In the exposure apparatus U3b of the third embodiment, the mask holding mechanism 11a includes a mask holding cylinder 21a for holding the mask MA, a guide roller 93 for supporting the mask holding cylinder 21a, and a driving roller for driving the mask holding cylinder 21a 94, and the driving part 96.

The mask holding cylinder 21a forms a mask surface for arranging the illumination area IR on the mask MA. In this embodiment, the mask surface includes a surface (hereinafter referred to as a cylindrical surface) that rotates a line segment (generating bar) around an axis parallel to the line segment (the central axis of the cylindrical shape). The cylindrical surface is, for example, a cylindrical outer peripheral surface, a cylindrical outer peripheral surface, or the like. The mask holding cylinder 21a is made of, for example, glass or quartz, and has a cylindrical shape with a certain thickness, and its outer peripheral surface (cylindrical surface) forms a mask surface. That is, in the present embodiment, the illumination area IR on the mask MA is curved into a cylindrical surface with a certain radius of curvature Rm from the center line. The part of the mask holding cylinder 21a that overlaps with the pattern of the mask MA when viewed from the radial direction of the mask holding cylinder 21a, for example, the central part of the mask holding cylinder 21a other than the both ends in the Y-axis direction is opposed to the illumination beam EL1 With light transmittance.

The mask MA is, for example, a transmissive flat sheet mask with a pattern formed on one side of a long strip of ultra-thin glass plate with good flatness (for example, a thickness of 100-500μm) with a shading layer such as chromium, so that it follows the light The cover keeps the outer peripheral surface of the cylinder 21a curved, and is used in a state of being wound (attached to) the outer peripheral surface. The mask MA has a pattern non-formation area where no pattern is formed, and is attached to the mask holding cylinder 21a in the pattern non-formation area. The mask MA is detachable to the mask holding cylinder 21a. The mask MA is the same as the mask M of the first embodiment. It can replace the method of the mask holding cylinder 21a wound around the transparent cylindrical base material, and the mask of the transparent cylindrical base material can be kept round. The outer peripheral surface of the tube 21a is directly integrated with a mask pattern formed by forming a light shielding layer such as chromium. In this case, the mask holding cylinder 21a also functions as a holding member of the mask.

The guide roller 93 and the drive roller 94 extend in the Y-axis direction parallel to the central axis of the mask holding cylinder 21a. The guide roller 93 and the driving roller 94 are arranged to be able to rotate around an axis parallel to the central axis. The outer diameters of the guide roller 93 and the driving roller 94 are larger than the other parts in the axial direction, and this end is circumscribed to the mask holding cylinder 21a. As described above, the guide roller 93 and the driving roller 94 are arranged so as not to contact the mask MA held by the mask holding cylinder 21a. The driving roller 94 is connected to the driving part 96. The driving roller 94 transmits the torque supplied from the driving portion 96 to the mask holding cylinder 21a to rotate the mask holding cylinder 21a around the central axis.

In addition, although the mask holding mechanism 11a has one guide roller 93, the number is not limited, and it may be two or more. Similarly, although the mask holding mechanism 11a includes one drive roller 94, the number is not limited, and it may be two or more. At least one of the guide roller 93 and the drive roller 94 may be arranged inside the mask holding cylinder 21a, and in contact with the mask holding cylinder 21a. In addition, the portion of the mask holding cylinder 21a that does not overlap with the pattern of the mask MA as viewed from the radial direction of the mask holding cylinder 21a (both ends in the Y-axis direction) may also have translucency for the illumination light beam EL1. May not have light transmittance. In addition, one or both of the guide roller 93 and the drive roller 94 may have a truncated cone shape, for example, and the central axis (rotation axis) of the guide roller 93 and the drive roller 94 may be non-parallel to the central axis.

The light source device 13a of the present embodiment includes a light source (not shown) and an illumination optical system ILa. The illumination optical system ILa is provided with a plurality of (for example, six) illumination optical systems ILa1 to ILa6 arranged in the Y-axis direction corresponding to each of the plurality of projection optical systems PL1 to PL6. As the light source, various light sources can be used in the same way as the aforementioned various light source devices 13a. The illumination light emitted from the light source has a uniform illuminance distribution, and is divided into a plurality of illumination optical systems ILa1 to ILa6 through a light guide member such as an optical fiber.

Each of the plurality of illumination optical systems ILa1 to ILa6 includes a plurality of optical members such as lenses. Each of the plurality of illumination optical systems ILa1 to ILa6, including, for example, an integrator optical system, a rod lens, a fly-eye lens, etc., illuminates the illumination area IR with an illumination light beam EL1 having a uniform illuminance distribution. In this embodiment, a plurality of illumination optical systems ILa1 to ILa6 are arranged inside the mask holding cylinder 21a. Each of the plurality of illumination optical systems ILa1 to ILa6 illuminates each illumination area on the mask MA held on the outer peripheral surface of the mask holding cylinder 21a from the inside of the mask holding cylinder 21a through the mask holding cylinder 21a.

The light source device 13a guides the light emitted from the light source through the illumination optical systems ILa1 to ILa6, and irradiates the guided illumination beam EL1 to the mask MA from the inside of the mask holding cylinder 21a. The light source device 13 illuminates a part (illumination area IR) of the mask MA held by the mask holding cylinder 11a with uniform brightness by the illumination light beam EL1. In addition, the light source may also be arranged inside the mask holding cylinder 21a, or may be arranged outside the mask holding cylinder 21a. In addition, the light source may be a device (external device) different from the exposure device U3b.

Exposure device U3a, when using a transmissive mask as a mask, is the same as the exposure devices U3 and U3a, by setting the relationship between the projected image surface and the exposure surface as described above to have two locations on the exposure surface as the best The relationship between the position of the focus state, and the same effect as the above can be obtained.

[Fourth Embodiment] Next, the exposure apparatus U3c of the fourth embodiment will be described with reference to FIG. 19. In order to avoid repetitive descriptions, only the differences from the first embodiment will be described, and the same components as those of the first embodiment will be described with the same reference numerals as in the first embodiment. Fig. 19 is a diagram showing the overall configuration of an exposure apparatus (substrate processing apparatus) of the fourth embodiment. Although the exposure apparatus U3 of the first embodiment uses a structure that holds a cylindrical reflective mask M in the rotatable mask holding cylinder 21, the exposure apparatus U3c of the fourth embodiment uses a flat plate The reflection type mask MB is held by a movable mask holding mechanism 11b.

In the exposure apparatus U3c of the fourth embodiment, the mask holding mechanism 11b includes a mask stage 110 for holding the flat mask MB, and the mask stage 110 is arranged along the X direction in a plane orthogonal to the center plane CL Scan for moving mobile devices (illustration omitted).

Since the plane P1 of the mask MB in FIG. 19 is a plane substantially parallel to the XY plane, the chief ray of the projection light beam EL2 reflected from the mask MB is perpendicular to the XY plane. Therefore, the chief rays of the illumination beam EL1 from the illumination optical systems IL1 to IL6 in the illumination regions IR1 to IR6 on the illumination mask MB are also arranged to be perpendicular to the XY plane.

When the principal ray of the illumination beam EL1 illuminating the mask MB is perpendicular to the XY plane, the polarization beam splitter PBS is configured to enter the quarter-wave plate 41. The incident angle θ1 of the principal ray of the illumination beam EL1 becomes Brewster angle θB, the chief ray of the illumination beam EL1 reflected on the quarter wave plate 41 is perpendicular to the XY plane. Along with the change of the configuration of the polarization beam splitter PBS, the configuration of the illumination optical module ILM is also appropriately changed.

In addition, when the chief ray of the projection light beam EL2 reflected from the mask MB is perpendicular to the XY plane, the first reflection surface P3 of the first deflection member 70 included in the first optical system 61 of the projection optical module PLM is The angle is set to reflect the projection light beam EL2 from the polarization beam splitter PBS, and the reflected projection light beam EL2 passes through the first lens group 71 and enters the first concave mirror 72. Specifically, the first reflecting surface P3 of the first deflecting member 70 is substantially set at 45° with respect to the second optical axis BX2 (XY plane).

In addition, in the fourth embodiment, similar to the previous figure 2, when viewed in the XZ plane, from the center point of the illumination area IR1 (and IR3, IR5) on the mask MB to the center of the illumination area IR2 (and IR4, IR6) The perimeter of the point in the X direction is set to be from the center point of the projection area PA1 (and PA3, PA5) on the substrate P along the supporting surface P2 to the center point of the second projection area PA2 (and PA4, PA6) The perimeters are substantially equal.

The same applies to the exposure device U3c of FIG. 19. The lower control device 16 controls the moving device of the mask holding mechanism 11 (linear motor for scanning exposure or actuator for micro-movement, etc.) in synchronization with the rotation of the substrate support cylinder 25 The photomask carrier 110 is driven. The exposure device U3c of Fig. 19 must perform scanning exposure during the synchronous movement of the mask MB in the +X direction, and then perform an action (rewind) to return the mask MB to the initial position in the -X direction. Therefore, when the substrate support cylinder 25 is continuously rotated at a constant speed and the substrate P is continuously fed at a constant speed, the pattern on the substrate P is not exposed during the rewinding operation of the mask MB, but is tied to the substrate Patterns for panels are formed intermittently (separately) in the conveying direction of P. However, in practice, since the speed of the substrate P during scanning exposure (here, the peripheral speed) and the speed of the photomask MB are assumed to be 50-100 mm/s, only the photomask should be loaded when the photomask MB is rolled back. The stage 110 is driven at the highest speed of, for example, 500 mm/s, which can reduce the blank space of the panel pattern formed on the substrate P in the conveying direction.

Next, the relationship between the projection image surface of the mask pattern and the exposure surface of the substrate in the exposure apparatus U3c of the fourth embodiment will be described with reference to FIG. 20. 20 is an explanatory diagram illustrating the relationship between the projected image surface of the pattern of the photomask and the exposure surface of the substrate.

The exposure device U3c uses the projection optical system PL to image the projection light beam EL2 to form the projection image surface Sm2 of the pattern of the mask MB. The projection image surface Sm2 is the position where the pattern of the mask MB is imaged, and is the best focus position. Here, the mask MB is arranged in a plane as described above. Thereby, the projection image surface Sm2 also becomes a flat surface (a straight line in the ZX plane). In addition, in the exposure device U3c, the surface of the substrate P is the exposure surface Sp. Here, the so-called exposure surface Sp is the surface of the substrate P. The substrate P is held by the cylindrical substrate support cylinder 25 as described above. Thereby, the exposure surface Sp becomes a curved surface (curve in the ZX plane) of the radius of curvature Rm. In addition, the exposure surface Sp is an axis whose direction orthogonal to the scanning exposure direction is a curved surface. Therefore, the exposure surface Sp shown in FIG. 20 becomes a curved curve with respect to the scanning exposure direction. The exposure surface Sp, the amount of change in the position of the exposure width A in the scanning exposure direction in the projection area PA is Δp. The projection image surface Sm2 is a flat surface. Therefore, the amount of change in the position of the exposure width A in the scanning exposure direction in the projection area PA is zero. Here, in the exposure device U3c, the position of the exposure surface Sp with respect to the projection image surface Sm2 is set as the actual exposure surface Spa. The actual exposure surface Spa intersects at two positions Pa2, Pb2 that are different from the projection image surface Sm2 in the scanning exposure direction. In addition, the exposure device U3c can adjust the position of each optical member of the projection optical system PL or adjust the distance between the mask MB and the substrate P by either of the mask holding mechanism 11b and the substrate support mechanism 12, so as to be relative to the projection The position of the exposure surface of the image surface Sm2 changes.

In the exposure device U3c, the projected image surface Sm2 and the actual exposure surface Spa intersect at two different positions Pa2, Pb2, whereby within the exposure width A, the focus state becomes the most in the position Pa2 on the actual exposure surface Spa Good focus, the focus state becomes the best focus in the position Pb2 on the actual exposure surface Spa.

The exposure device U3c, even if the surface of the mask MB is flat and the surface of the substrate P is cylindrical, it can project the mask pattern to the scanning exposure direction of the substrate P in the same way as the exposure devices U3, U3a, U3b The projection image surface Sm2 and the exposure surface Sp of the substrate P to be exposed are given a cylindrical shape difference. Furthermore, in the exposure device U3c, the projected image surface Sm2 and the actual exposure surface Spa intersect at two different positions Pa2, Pb2, and the focus state of the exposure surface becomes the best focus in the two different positions.

In this way, the exposure device U3c also uses the photomask to maintain the rotational movement of the cylinder 21 to continuously change the focus state within the exposure width A of the scanning exposure direction, thereby suppressing the image contrast relative to the actual focus. Variety. In addition, the exposure device U3c can also obtain the same various effects as the exposure device U3. As described above, even when only one of the projection image surface and the exposure surface (the surface of the substrate P) is curved, the same effect as when both the projection image and the exposure surface are curved.

來求出。Here, the exposure device U3c can calculate the arc-shaped variation within the exposure width A by the following formula that sets the cylindrical radius r ₁ of the projection image surface Sm2 in the scanning exposure direction of the substrate P of the above formula to 0 Focus width Δ. Δ=r ₂ -((r ₂ ² )-(A/2) ² ) ^1/2 Here, in the exposure device U3c, since the radius of curvature of the projection image surface Sm2 of the mask pattern is ∞, the exposure width A The defocus characteristic Cm, which changes in the shape of an inner arc, can only be obtained by the previous formula 3. That is, the defocus characteristic Cm (=ΔRp) in the case of the exposure device U3c is expressed as [Equation 5]

Come find out.

In the exposure apparatus of the present embodiment, among the mask holding mechanism and the substrate support mechanism, the curved surface holder is used as the first support member, and the curved surface or flat surface supported is used as the second support member.

＜Exposure method＞ Next, the exposure method will be described with reference to FIG. 21. Figure 21 is a flow chart showing the exposure method.

In the exposure method shown in FIG. 21, first, the substrate P is supported on the supporting surface P2 by the substrate supporting mechanism (step S101), and the mask M is supported on the surface P1 by the mask holding mechanism (step S102). Thereby, the photomask M and the substrate P are in an opposed state. In addition, the order of step S101 and step S102 can be reversed. In addition, any one of the surface P1 and the support surface P2 is the first surface, and the other is the second surface. The first surface is curved into a cylindrical surface shape with a predetermined curvature.

Next, adjust the focus position relative to the exposure surface (step S103). Specifically, within the exposure width A of the projection area PA set on the surface of the substrate P, the focus position is set at a position including two best focus positions in the scanning exposure direction.

After the adjustment of the focus position is completed, the relative movement (rotation) of the scanning exposure direction of the substrate P and the mask M is started (step S104). That is, at least one of the substrate support mechanism and the mask holding mechanism starts an operation of moving at least one of the substrate P and the mask M in the scanning exposure direction.

After the relative movement is started, the projection of the projection light beam in the projection area PA is started (step S105). That is, the light beam from the pattern of the mask placed in the illumination area IR of the illumination light is projected onto the projection area PA where the substrate P is placed. Thereby, the exposure method shown in FIG. 21 is to project a beam of light including two best focus positions in the scanning exposure direction on the projection area on the exposure surface of the substrate P.

The exposure method is based on the above method. By projecting the light beam after adjusting the focus position, the light beam including two best focus positions in the scanning exposure direction can be projected on the projection area on the exposure surface of the substrate P. Thereby, the various effects mentioned above can be obtained. In addition, although this embodiment describes the case of adjusting the focus position, depending on the setting of the device, a position including two best focus positions in the scanning exposure direction may be the focus position.

＜Component manufacturing method＞ Next, referring to FIG. 22, a method of manufacturing the element will be described. Fig. 22 is a flowchart showing a component manufacturing method of the component manufacturing system.

In the device manufacturing method shown in FIG. 22, first, the function and performance design of a display panel formed using a self-luminous device such as organic EL is performed, and the required circuit patterns and wiring patterns are designed by CAD or the like (step S201). Then, according to the various patterns of each layer designed by CAD or the like, a mask M of the required layer amount is produced (step S202). And prepare the supply roll FR1 wound with the flexible substrate P (resin film, metal foil film, plastic, etc.) as the base material of the display panel (step S203). In addition, the roll-shaped substrate P prepared in this step S203 may be one whose surface has been modified as needed, or one that has been formed in advance (for example, micro-concave and convex through imprint method), or one that is pre-laminated with light. Inductive functional film or transparent film (insulating material).

Next, on the substrate P, the electrodes constituting the display panel elements or the backplane layer composed of wiring, insulating film, TFT (thin film semiconductor), etc. are formed, and a light emitting element composed of self-luminous elements such as organic EL is formed by stacking on the substrate. Layer (display pixel portion) (step S204). In this step S204, although it includes the conventional lithography process of exposing the photoresist layer using the exposure device U3 described in the previous embodiments, it also includes the pattern of the substrate P coated with a photosensitive silane coupling agent instead of the photoresist Exposure comes from an exposure process that forms a water-repellent pattern on the surface, a wet process that exposes the photo-sensitive catalyst layer pattern and forms a metal film pattern (wiring, electrode, etc.) by electroless plating, or contains silver The processing of printing process, etc. for drawing patterns such as conductive ink of rice particles.

Then, cut the substrate P for each display panel element continuously manufactured on the long substrate P in a roll manner, or attach a protective film (environmental barrier layer) or color filter film on the surface of each display panel element, etc., Assemble components (step S205). Next, a step of checking whether the display panel element can operate normally or whether it meets the desired performance and characteristics is performed (step S206). Through the above methods, display panels (flexible displays) can be manufactured.

1: Component manufacturing system 2: Substrate supply device 4: Substrate recovery device 5: Upper control device 11: Mask holding mechanism 12: Substrate support mechanism 13: Light source device 16: Lower control device 21: The photomask keeps the cylinder 25: Substrate support cylinder 31: light source 32: Light guide member 41:1/4 wavelength plate 51: collimating lens 52: compound eye lens 53: Condenser lens 54: Cylindrical lens 55: Illumination field diaphragm 56: Relay lens 61: First Optical Department 62: The second optical system 63: Projection field diaphragm 64: Focus correction optics 65: Optical components for image shift 66: Optical components for magnification correction 67: Rotation correction mechanism 68: Polarization adjustment mechanism 70: The first deflection member 71: The first lens group 72: The first concave mirror 80: The second deflection member 81: The second lens group 82: The second concave mirror 110: Mask stage P: substrate FR1: Supply reel FR2: Reel for recycling U1~Un: Processing device U3: Exposure device (substrate processing device) M, MA: Mask AX1: 1st axis AX2: 2nd axis P1: The face of the mask P2: bearing surface P7: Intermediate image surface EL1: Illumination beam EL2: Projection beam Rm: radius of curvature Rp: radius of curvature CL: center plane PBS: Polarizing beam splitter IR1～IR6: Illumination area IL1～IL6: Illumination Optics ILM: Illumination Optical Module PA1～PA6: Projection area PLM: Projection Optical Module

[Fig. 1] A diagram showing the structure of the device manufacturing system of the first embodiment. [Fig. 2] A diagram showing the overall configuration of the exposure apparatus (substrate processing apparatus) of the first embodiment. [Fig. 3] is a diagram showing the arrangement of the illumination area and projection area of the exposure device shown in Fig. 2. [Fig. 4] is a diagram showing the configuration of the illumination optical system and the projection optical system of the exposure device shown in Fig. 2. [Fig. 5] A diagram showing the state of the illumination beam and the projection beam in the mask exaggeratedly. [Fig. 6A] is an explanatory diagram showing the relationship between the projected image surface of the pattern of the photomask and the exposure surface of the substrate. [Figure 6B] is a graph showing how the defocus amount changes within the exposure width. [Fig. 7] A diagram showing the overall configuration of an exposure apparatus (substrate processing apparatus) of the second embodiment. [Figure 8] is an explanatory diagram showing the relationship between the projected image surface of the photomask pattern and the exposure surface of the substrate. [Figure 9] A graph showing an example of the relationship between exposure coordinates and defocus. [Figure 10] A graph showing an example of the relationship between defocus and point image intensity. [Fig. 11] A graph showing an example of the relationship between the change in defocus amount and the intensity difference. [Figure 12] A graph showing an example of the relationship between the amount of defocus and the contrast change of L/S. [Figure 13] A graph showing an example of the relationship between the amount of defocus and the change in the contrast ratio of L/S. [Figure 14] is a graph showing an example of the relationship between the amount of defocus, L/S CD and clipping level. [Figure 15] A graph showing an example of the relationship between the amount of defocus and the contrast change of isolated lines. [Figure 16] A graph showing an example of the relationship between the amount of defocus and the change in the contrast ratio of the isolated line. [Figure 17] A graph showing an example of the relationship between the amount of defocus and the CD of the isolated line and the cut level. [Fig. 18] A diagram showing the overall configuration of an exposure apparatus (substrate processing apparatus) of the third embodiment. [Fig. 19] A diagram showing the overall configuration of an exposure apparatus (substrate processing apparatus) of the fourth embodiment. [Figure 20] is an explanatory diagram showing the relationship between the projected image surface of the photomask pattern and the exposure surface of the substrate. [Figure 21] is a flowchart showing the exposure method. [Fig. 22] is a flowchart of a manufacturing method of a display element.

A: Exposure width

Ae, As: end

AX1: 1st axis

AX2: 2nd axis

FC1, FC2, FC3: location

PA: projection area

Rm: radius of curvature

Rp: radius of curvature

Sm: Projection image surface

Spa: actual exposure

Sp: Exposure surface

Claims (15)

A scanning exposure device that makes a mask holding cylinder that holds a mask pattern along a circumferential surface curved from a first axis at a first radius, rotates around the first axis, and moves a flexible substrate along the The scanning exposure direction of the surface to expose the mask pattern on the surface of the substrate, which has: The illumination optical system irradiates illumination light toward the illumination area, and the illumination area is set on the mask pattern to be an elongated rectangle or rectangle in the direction of the first axis, and set to be on the circumference corresponding to the scanning exposure direction The circumferential direction of the face has a predetermined width; The projection optical system projects the light beam from the mask pattern that appears in the illumination area to the projection area on the substrate side corresponding to the illumination area, so that the image of the mask pattern is aligned along the corresponding first The image is formed in a way that the radius of the projection image is curved in the aforementioned scanning exposure direction; and The substrate support cylinder is supported by bending the substrate from a second shaft arranged in parallel with the first axis at a second radius into a cylindrical outer peripheral surface, and rotates around the second axis to make The substrate moves in the circumferential direction of the outer circumferential surface corresponding to the scanning exposure direction; The mask holding cylinder, the substrate support cylinder, and the projection optical system are set so that the curved projection image surface and the curved surface of the substrate intersect at two places separated from the scanning exposure direction in the projection area. . For example, the scanning exposure apparatus of the first item of the scope of patent application, wherein each of the projection optical system, the mask holding cylinder, and the substrate support cylinder is set to be projected on the substrate by the projection optical system When the defocus amount of the projection area of the light beam in the midpoint of the scanning exposure direction is set to Δ, and the focal depth of the projection optical system is set to DOF, 0.5<Δ/DOF≦3 is satisfied. For example, the scanning exposure device of the second item of the scope of patent application is set so that the relationship between the aforementioned defocus amount Δ and the aforementioned focal depth DOF satisfies 1≦Δ/DOF. Such as the scanning exposure device of the second item of the patent application, wherein the defocus amount of the projection image surface of the mask pattern and the surface of the substrate in the projection area is projected with the best focus by the projection optical system, It is set to change line-symmetrically in the scanning exposure direction with the position of the midpoint of the projection area in the scanning exposure direction as an axis. For example, the scanning exposure device of any one of items 1 to 4 in the scope of patent application, wherein the aforementioned projection optical system has a plurality of divided projection optical systems; The split projection optical system is arranged in a row in a direction in which the first axis and the second axis extend and is orthogonal to the scanning exposure direction, and projects the light beams to the corresponding projection regions. For example, the scanning exposure device of item 5 of the scope of patent application, wherein the plurality of split projection optical systems are arranged in at least two rows in the scanning exposure direction, and are arranged adjacent to the direction orthogonal to the scanning exposure direction The ends of the projection regions corresponding to the split projection optical systems overlap with each other. For example, the scanning exposure device of the sixth item of the scope of patent application, which is configured so that when the exposure width of the projection area corresponding to each of the plurality of divided projection optical systems in the scanning exposure direction is accumulated, the accumulated value is The direction orthogonal to the aforementioned scanning exposure direction is constant. For example, the scanning exposure device of the 6th or 7th patent application, wherein each of the plurality of divided projection optical systems is provided by a plurality of deflecting members, lens groups, and lens groups that deflect the optical path of the light beam from the mask pattern. And the concave mirror arranged on the pupil surface is configured as a telecentric catadioptric optical system that deforms the Dyson system. For example, the scanning exposure device of any one of items 1 to 4 in the scope of patent application, wherein when the exposure width of the projection area in the scanning exposure direction is set to A, and the radius of the curved projection image surface is set to r _1. When the radius of the curved substrate surface is set to r ₂ , the numerical aperture of the projection optical system is set to NA, and the wavelength of the illumination light is set to λ, it is set to satisfy 0.5×(λ/NA ^{_{2) <r 1 - ((}} r 1 2) - (A / 2) 2) 1/2 + r 2 - ((r 2 2) - (A / 2) 2) 1/2 ≦ 3 × λ / NA 2 The relationship. For example, the scanning exposure device of item 9 of the scope of patent application, wherein the exposure width A, the radius r ₁ , the radius r ₂ , the numerical aperture NA, and the wavelength λ are further set to satisfy (λ/NA ² )< ^{_{r 1 - ((r 1 2}} ) - (A / 2) 2) 1/2 + r 2 - ((r 2 2) - (A / 2) 2) ^1/2 of the relationship. A scanning exposure method that moves a flexible substrate and a photomask pattern in a scanning exposure direction relative to a projection optical system to expose the photomask pattern on the surface of the substrate, comprising: The operation of rotating the mask holding cylinder with the first axis as the center while holding the mask pattern along the first circumferential surface curved at a predetermined radius from the first axis of the mask holding cylinder; In a state where the substrate is supported by bending and supporting the substrate along the substrate support cylinder from the second axis set parallel to the first axis and the second circumferential surface bent at a predetermined radius, the substrate is supported by the second axis. The rotation of the supporting cylinder; The action of irradiating the illumination light toward the illumination area, the illumination area is set on the mask pattern to be an elongated rectangle or rectangle in the direction of the first axis, and set to be on the first circumferential surface and the scanning exposure direction The corresponding circumferential direction has a predetermined width; and By projecting the light beam from the mask pattern that appears in the illumination area to the projection area on the substrate side corresponding to the illumination area by the projection optical system, the image of the mask pattern is aligned along the corresponding first circle The radius of the surface forms images on the projection image surface curved in the scanning exposure direction, and the positional relationship between the projection image surface and the surface of the substrate in the focusing direction is set to be the curved projection image surface and the curved surface of the substrate in the projection The action of intersecting two separate areas in the scanning exposure direction. For example, the scanning exposure method of claim 11, wherein the curved projection image surface and the curved substrate surface are curved in opposite directions in the focusing direction. For example, the scanning exposure method of item 11 or 12 in the scope of patent application, wherein each of the projection optical system, the mask holding cylinder, and the substrate support cylinder is set to be projected on by the projection optical system When the defocus amount of the projection area of the light beam on the substrate in the midpoint of the scanning exposure direction is set to Δ, and the focal depth of the projection optical system is set to DOF, 0.5<Δ/DOF≦3 is satisfied. Such as the scanning exposure method of item 13 in the scope of patent application, wherein the relationship between the aforementioned defocus amount Δ and the aforementioned focal depth DOF is set to satisfy 1≦Δ/DOF. Such as the scanning exposure method of item 13 of the scope of patent application, wherein the projection optical system is used to project the curved projection image surface of the mask pattern in the projection area with the best focus and the surface of the curved substrate The defocus amount is set to change line-symmetrically in the scanning exposure direction with the position of the midpoint of the projection area in the scanning exposure direction as an axis.

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