TW201908877A - Scanning exposure device and scanning exposure method - Google Patents

Abstract

To provide a device production method capable of producing substrates having high quality at high productivity. An exposure method for projecting a light flux from a pattern of a mask M arranged in an illumination region of illumination light on a projection region in which a substrate is arranged via a projection optical system includes: supporting such that one of the mask and the substrate goes along a first surface curved in a cylindrical shape at a predetermined curvature in one region of an illumination region and a projection region; supporting such that the other of the mask and the substrate goes along a predetermined second surface in the other region of the illumination region and projection region; rotating one of the mask and the substrate supported along the first surface along the first surface and moving the other of the mask and the substrate supported along the second surface in a scanning exposure direction; and projecting a light flux in which best focusing position is contained at two positions in the a scanning exposure direction in an exposure surface of the substrate from the projection optical system to the projection region.

Description

   Scanning exposure device and scanning exposure method   

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

As a substrate processing apparatus, there is a projection exposure apparatus described in Patent Document 2. The projection exposure device described in Patent Document 2 includes a substrate holder, which holds the photosensitive substrate on a substrate stage so that the surface of the photosensitive substrate and the pattern image projected by the projection optical system are optimally imaged in a one-dimensional moving direction. The relative tilt of the surface is a certain amount; and the driving means of the holder is to move the substrate holder to the projection optical system in linkage with the movement of the one-dimensional direction of the substrate stage so as to move along the tilt direction of the photosensitive substrate during scanning exposure Optical axis direction. With the above configuration, the projection exposure device can change the focused state of the light beam projected on the exposure surface of the photosensitive substrate according to the position of the scanning exposure in the one-dimensional direction.

[Advanced technical literature]

[Patent Document 1] International Publication No. 2008/029917

[Patent Document 2] Japanese Patent No. 2830492

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 is generated due to the shift of the relative relationship between the mask and the substrate or the shift of the optical system. When changing, exposure can also be performed in a focused state including an optimal focus position. This makes it possible to suppress a change in the contrast of the image exposed on the photosensitive substrate (photoresist layer).

However, the projection exposure apparatus described in Patent Document 2 uses a substrate holder to tilt a substrate with respect to a projection optical device (projection optical system). Therefore, adjustment (control) of the relative position becomes complicated. In particular, in the step-and-scan method in which each of a plurality of exposed areas (each irradiation) on the substrate is scanned relative to the photomask and the substrate to move the substrate in steps, each of the exposed areas on the substrate must be scanned. High-speed exposure repeatedly controls the inclination and movement of the substrate holder to the focus direction, which makes the control complicated and causes vibration.

In addition, in the 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 is reduced. 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 be reduced in some cases.

An aspect of the present invention is to provide a substrate processing apparatus, a device manufacturing method, and an exposure method capable of producing a high-quality substrate with high productivity.

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 disposed on a mask disposed on an illumination light illumination region onto a projection region on which the substrate is disposed, including: a first support member, The second support member is configured to support one of the photomask and the substrate along a first surface that is curved into a cylindrical surface shape with a predetermined curvature in one of the illumination area and the projection area. Supporting the other of the photomask and the substrate along the predetermined second surface in the other of the illumination area and the projection area; and a moving mechanism for rotating the first support member to Either one of the photomask and the substrate supported by the first support member is moved in the scanning exposure direction; the projection optical system is on the exposure surface of the substrate, and will include two optimal focusing points in the scanning exposure direction The light beam at the position is projected on the aforementioned projection area.

According to a second aspect of the present invention, there is provided a device manufacturing method including: an operation of supplying the substrate to the substrate processing apparatus; and an operation of 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 disposed in an illumination light illumination area onto a projection area of the arrangement substrate, including: The movement of supporting one of the photomask and the substrate along a first surface that is curved into a cylindrical shape with a predetermined curvature in one area; along the other area of the illumination area and the projection area Supporting the operation of the other of the photomask and the substrate in a predetermined second surface manner; and rotating either of the photomask and the substrate supported by the first surface along the first surface, An operation of moving any one of the photomask and the substrate supported by the first surface in a scanning exposure direction; and projecting a light beam including two optimal focus positions in the scanning exposure direction on the exposure surface of the substrate In the aforementioned projection area.

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

1‧‧‧component manufacturing system

2‧‧‧ substrate supply device

4‧‧‧ substrate recovery device

5‧‧‧ host control device

11‧‧‧Mask holding mechanism

12‧‧‧ substrate support mechanism

13‧‧‧light source device

16‧‧‧ Lower control device

21‧‧‧Photomask holding cylinder

25‧‧‧ substrate support cylinder

31‧‧‧light source

32‧‧‧light guide

41‧‧‧1 / 4 wave plate

51‧‧‧ collimating lens

52‧‧‧Flying Eye Lens

53‧‧‧ condenser lens

54‧‧‧ cylindrical lens

55‧‧‧illumination field diaphragm

56‧‧‧ relay lens

61‧‧‧The first optical system

62‧‧‧Second Optical Department

63‧‧‧ projection field diaphragm

64‧‧‧ Focus Correction Optics

65‧‧‧Image shifting optical member

66‧‧‧Optical member for magnification correction

67‧‧‧rotation correction mechanism

68‧‧‧ Polarization adjustment mechanism

70‧‧‧The first deflection member

71‧‧‧1st lens group

72‧‧‧ 1st concave mirror

80‧‧‧The second deflection member

81‧‧‧ 2nd lens group

82‧‧‧ 2nd concave mirror

110‧‧‧Mask stage

P‧‧‧ substrate

FR1‧‧‧ supply reel

FR2‧‧‧Recycling roll

U1 ~ Un‧‧‧Processing device

U3‧‧‧ exposure device (substrate processing device)

M, MA‧‧‧Photomask

AX1‧‧‧1st axis

AX2‧‧‧ 2nd axis

P1‧‧‧Mask face

P2‧‧‧bearing surface

P7‧‧‧Middle image plane

EL1‧‧‧illuminating beam

EL2‧‧‧ Projected Beam

Rm‧‧‧Curvature radius

Rp‧‧‧curvature radius

CL‧‧‧ center plane

PBS‧‧‧polarized beam splitter

IR1 ~ IR6‧‧‧Lighting area

IL1 ~ IL6‧‧‧ Department of Lighting Optics

ILM‧‧‧Lighting Optical Module

PA1 ~ PA6‧‧‧‧ projection area

PLM‧‧‧Projection Optical Module

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

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

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

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

FIG. 5 is an exaggerated view showing states of an illumination light beam and a projection light beam in a photomask.

6A is an explanatory diagram showing a relationship between a projection image surface of a pattern of a photomask and an exposure surface of a substrate.

FIG. 6B is a graph showing changes in the amount of defocus over the exposure width.

FIG. 7 is a diagram showing the overall configuration of an exposure apparatus (substrate processing apparatus) according to a second embodiment.

8 is an explanatory diagram showing a relationship between a projection image surface of a pattern of a photomask and an exposed surface of a substrate.

FIG. 9 is a graph showing an example of the relationship between exposure coordinates and defocus.

FIG. 10 is a graph showing an example of the relationship between defocus and point image intensity.

FIG. 11 is a graph showing an example of the relationship between the change in defocus amount and the intensity difference.

FIG. 12 is a graph showing an example of the relationship between the defocus amount and the contrast change of L / S.

FIG. 13 is a graph showing an example of the relationship between the amount of defocus and the change in the contrast ratio of L / S.

FIG. 14 is a graph showing an example of the relationship between the defocus amount and the CD and clipping levels of L / S.

FIG. 15 is a graph showing an example of the relationship between the defocus amount and the contrast change of an isolated line.

FIG. 16 is a graph showing an example of the relationship between the amount of defocus and the change in the contrast ratio of the isolated line.

FIG. 17 is a graph showing an example of the relationship between the defocus amount and the CD and clipping level of the isolated line.

FIG. 18 is a diagram showing the overall configuration of an exposure apparatus (substrate processing apparatus) according to a third embodiment.

FIG. 19 is a diagram showing the overall configuration of an exposure apparatus (substrate processing apparatus) according to a fourth embodiment.

FIG. 20 is an explanatory diagram showing a relationship between a projection image surface of a pattern of a photomask and an exposure surface of a substrate.

FIG. 21 is a flowchart showing an exposure method.

Fig. 22 is a flowchart showing a method of manufacturing a device.

The aspect (embodiment) for implementing the present invention will be described in detail with reference to the drawings. The present invention is not limited to the contents described in the following embodiments. In addition, the constituent elements described below include those which are easily conceivable by a person having ordinary knowledge in the technical field to which the invention belongs, and also include substantially the same thing. The constituent elements described below can be appropriately combined. In addition, various omissions, substitutions, or changes of constituent elements can be made without departing from the gist of the present invention. For example, in the following embodiments, a case where a flexible display is manufactured as an element system will be described, but it is not limited to this. As an element, a wiring board, a semiconductor substrate, etc. can also be manufactured.

[First Embodiment]

The substrate processing apparatus of the first embodiment is an exposure apparatus that applies an exposure process to a substrate. In addition, the exposure apparatus is a component manufacturing system that is assembled by applying various processes to the exposed substrate to manufacture components. First, a component manufacturing system will be described.

<Component manufacturing system>

FIG. 1 is a diagram showing the configuration of a component manufacturing system according to the first embodiment. The component manufacturing system 1 shown in FIG. 1 is a production line (flexible display production line) that manufactures flexible displays as components. Examples of the flexible display include an organic EL display. This component manufacturing system 1 is configured to feed the flexible substrate P from a supply roll FR1 that has been wound into a roll, and then the substrate P is continuously subjected to various processes. The processed substrate is then processed. P is wound as a flexible element on a reel FR2 for recycling, a so-called roll-to-roll method. The component manufacturing system 1 of the first embodiment shows that the substrate P formed into a thin film is fed out from the supply roll FR1, and the substrate P sent out from the supply roll FR1 is sequentially passed through the n processing units U1 and U1. U2, U3, U4, U5, ... Un are examples of winding up to the reel FR2 for recycling. First, a substrate P that is a processing target of the element manufacturing system 1 will be described.

The substrate P is, for example, a foil made of a metal or alloy such as a resin film and stainless steel. The material of the resin film includes, for example, polyethylene resin, polypropylene resin, polyester resin, ethylene-vinyl copolymer resin, polyvinyl chloride resin, cellulose resin, polyamide resin, polyimide resin, and polycarbonate resin. 1 or more of polystyrene resin and vinyl acetate resin.

For the substrate P, it is preferable to select, for example, a thermal expansion coefficient that is significantly larger and can substantially ignore the amount of deformation caused by heat in various processes performed on the substrate P. The thermal expansion coefficient can be set to be smaller than a threshold value corresponding to a process temperature or the like, for example, by mixing an inorganic filler into a resin film. Examples of the inorganic filler include titanium oxide, zinc oxide, aluminum oxide, and silicon oxide. In addition, the substrate P may be a single-layered body of ultra-thin glass having a thickness of about 100 μm produced by a floating method or the like, or a laminated body in which the above-mentioned resin film, foil, or the like is bonded to this extremely 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 on the component manufacturing system 1. The component manufacturing system 1 equipped with the supply roll FR1 repeatedly performs various processes for manufacturing one component on the substrate P sent out from the supply roll FR1. Therefore, the processed substrate P is in a state where a plurality of elements are connected. That is, 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 pretreatment in advance, or a fine partition wall structure (concavo-convex structure) formed on the surface for precise patterning by a marking method.

The processed substrate P is wound into a roll shape and recovered as a recovery roll FR2. The reel FR2 is mounted on a cutting device (not shown). A cutting device equipped with a recycling roll FR2 divides (cuts) the processed substrate P into individual components, thereby forming a plurality of components. The size of the substrate P is, for example, about 10 cm to 2 m in the width direction (direction of the short side), and more than 10 m in the length direction (length direction). Of course, the size of the substrate P is not limited to the above-mentioned size.

Next, a component manufacturing system 1 will be described with reference to FIG. 1. In FIG. 1, the X direction, the Y direction, and the Z direction form an orthogonal coordinate system orthogonal to each other. The X direction is a direction connecting the supply roll FR1 and the recovery roll FR2 in a horizontal plane, and is the left-right direction in FIG. 1. The Y direction is a direction orthogonal to the X direction in the horizontal plane, and is the front-back direction in FIG. 1. The Y direction is the axial direction of the supply roll FR1 and the recovery roll FR2. The Z direction is a vertical direction, and it is a vertical direction in FIG. 1.

Element manufacturing system 1 includes a substrate supply device 2 for supplying a substrate P, a processing device U1 to Un that performs various processes on the substrate P supplied from the substrate supply device 2, and The substrate recovery device 4 and each device of the control element manufacturing system 1 have a higher-level control device 5.

A supply roll FR1 is rotatably mounted on the substrate supply device 2. The substrate supply device 2 includes a drive roller R1 that sends out a substrate P from a mounted 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 holding the front and back surfaces of the substrate P, and sends out the substrate P from the supply roll FR1 toward the transporting direction of the recovery roll FR2, thereby supplying the substrate P to the processing devices U1 to Un. At this time, the edge position controller EPC1 moves the substrate P in the width direction in such a manner that the position of the substrate P in the width direction end (edge) is within a range of ± decade μm to several tens μm relative to the target position. The position of the substrate P in the width direction is corrected.

A reel roll FR2 is rotatably mounted on the substrate recovery device 4. The substrate recovery device 4 includes a driving roller R2 that pulls the processed substrate P toward the recovery roll FR2 side, 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 holding 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 is configured in the same manner as the edge position controller EPC1, and the position of the substrate P in the width direction is corrected to prevent the width direction end (edge) of the substrate P from being uneven in the width direction.

The processing device U1 is a coating device that applies a photosensitive functional liquid to the surface of the substrate P supplied from the substrate supply device 2. As the photosensitive functional liquid, for example, a photoresist, a photosensitive silane coupling material (liquid-repellent modification material), a photosensitive plating reduction material, and a UV-curable resin solution are used. The processing device U1 is sequentially provided with a coating mechanism Gp1 and a drying mechanism Gp2 from the upstream side in the conveying direction of the substrate P. The coating mechanism Gp1 includes a pressure roller DR1 that winds the substrate P, and a coating roller DR2 that faces the pressure roller DR1. The coating mechanism Gp1 holds the substrate P with the pressure roller DR1 and the coating roller DR2 in a state where the supplied substrate P is wound on the pressure roller DR1. Next, the coating mechanism Gp1 rotates the pressure 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 dry 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 a photosensitivity on the substrate P. Functional layer.

The processing device U2 is a heating device that heats the substrate P transferred from the processing device U1 to a predetermined temperature (for example, about several 10 to 120 ° C.) in order to stabilize the photosensitive functional layer formed on the surface of the substrate P. The processing device U2 is provided with a heating chamber HA1 and a cooling chamber HA2 in this order from the upstream side in the transport direction of the substrate P. The heating chamber HA1 is provided with a plurality of rollers and a plurality of air turn bars inside, and the plurality of rollers and a plurality of air turn bars constitute a conveying path of the substrate P. A plurality of rollers are provided so as to be in contact with the back surface of the substrate P, and a plurality of air reversing levers are provided on the surface side of the substrate P in a non-contact state. The plurality of rollers and the plurality of air reversing levers are elongated conveying paths of the substrate P, and meandering conveying paths. The substrate P in the heating chamber HA1 is heated to a predetermined temperature while being conveyed along a meandering conveyance path. The cooling chamber HA2 cools the substrate P to the ambient temperature so that the temperature of the substrate P heated in the heating chamber HA1 is consistent with the ambient temperature of the post-processing (processing device U3). The cooling chamber HA2 is provided with a plurality of rollers and a plurality of rollers in the same manner as the heating chamber HA1 and is arranged in a meandering conveying path in order to lengthen the conveying path of the substrate P. The substrate P in the cooling chamber HA2 is cooled while being transported along a meandering transport path. A driving roller R3 is provided on the downstream side in the conveying direction of the cooling chamber HA2, and the driving roller R3 rotates while holding the substrate P passing through the cooling chamber HA2, thereby supplying the substrate P to the processing device U3. In addition, the heating chamber HA1 heats the substrate P. When the substrate P is a resin film such as PET (polyethylene terephthalate) or PEN (poly 2,6-naphthalene dicarboxylate), it can be set to not. Exceeds its glass transition temperature.

The processing device (substrate processing device) U3 is an exposure device that projects a pattern such as a circuit or a wiring for a substrate (photosensitive substrate) P supplied from the processing device U2 with 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 illumination beam, and projects and exposes the projection beam obtained by reflecting the illumination beam by the mask M on the substrate P. The processing device U3 includes a driving roller R4 that transports 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 drive roller R4 rotates while holding both the front and back surfaces of the substrate P to feed the substrate P to the downstream side in the conveying direction, thereby supporting the substrate P toward the substrate support roll (rotating roll (also (Weighing reel).

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 (substrate support roll) becomes the target position. In addition, the processing device U3 includes two sets of driving rollers R5 and R6 that transport the substrate P to the downstream side in the conveying direction in a state where the exposed substrate P is loosened. The two sets of driving rollers R5 and R6 are spaced apart in the conveying direction of the substrate P. At a predetermined interval. The driving roller R5 rotates on the upstream side of the substrate P being conveyed, and the driving roller R6 rotates on the downstream side of the substrate P being conveyed, thereby supplying the substrate P to the processing device U4. At this time, since the substrate P has been given slack, it is possible to absorb fluctuations in the conveying speed which are located downstream of the driving roller R6 in the conveying direction, and it is possible to cut off the influence of the changes in the conveying speed on the exposure processing of the substrate P. In addition, an alignment microscope AM1 is provided in the processing device U3 to perform alignment of the image of a part of the mask pattern of the mask M and the relative position of the substrate P and detect an alignment mark or the like formed on the substrate P in advance. , AM2.

The processing device U4 is a wet processing device that performs wet development processing, electroless plating processing, and the like on the exposed substrate P transferred from the processing device U3. The processing device U4 includes three processing tanks BT1, BT2, and BT3 and a plurality of rollers for transporting the substrate P in the vertical direction (Z direction). The plurality of rollers are arranged such that the substrate P sequentially passes through the conveying paths inside the three processing tanks BT1, BT2, and BT3. A driving roller R7 is provided downstream of the processing tank BT3 in the conveying direction. The driving roller R7 rotates while holding the substrate P passing through the processing tank BT3 to supply the substrate P to the processing apparatus U5.

Although not shown, the processing device U5 is a drying device for drying the substrate P transferred from the processing device U4. The processing device U5 removes droplets or mist droplets (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 several processing devices. After being processed by the processing apparatus Un, the substrate P is wound on the reel FR2 for recycling of the substrate recovery apparatus 4.

The higher-level control device 5 controls the substrate supply device 2, the substrate recovery device 4, and a plurality of processing devices U1 to Un. The higher-level control device 5 controls the substrate supply device 2 and the substrate recovery device 4, and transfers the substrate P from the substrate supply device 2 to the substrate recovery device 4. In addition, the higher-level control device 5 controls a plurality of processing devices U1 to Un in synchronization with the conveyance of the substrate P to perform various processes on the substrate P.

<Exposure device (substrate processing device)>

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 an exposure apparatus (substrate processing apparatus) according to the first embodiment. FIG. 3 is a diagram showing the arrangement of an illumination area and a projection area of the exposure apparatus shown in FIG. 2. FIG. 4 is a diagram showing a configuration of an illumination optical system and a projection optical system of the exposure apparatus 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 projects a mask pattern image formed on the outer peripheral surface of the cylindrical mask M while conveying the substrate P in the conveying direction (scanning direction), and exposes To the surface of the substrate P. In FIG. 2, the orthogonal coordinate system in which the X, Y, and Z directions are orthogonal is the same orthogonal coordinate system as that in FIG. 1.

First, the mask M used for the exposure apparatus U3 is demonstrated. The photomask M is, for example, a reflective photomask using a metal cylindrical body. The photomask M is formed as a cylindrical body having a peripheral surface (peripheral surface) having a radius of curvature 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 on which a predetermined mask pattern is formed. The surface P1 of the mask M includes a highly reflective portion that reflects the light beam in a predetermined direction with high efficiency, and a reflection suppression portion that does not reflect the light beam in the predetermined direction or reflects with low efficiency. The mask pattern is formed of a high reflection portion and a reflection suppression portion. Therefore, the reflection suppressing section may also absorb or transmit light, and may reflect (for example, scatter) outside the predetermined direction. Here, the mask M can be made of a material that absorbs light or a material that transmits light. As the exposure device U3, a mask made of a metal cylindrical body can be used as the mask M having the above-mentioned configuration. Therefore, the exposure apparatus U3 can perform exposure using an inexpensive mask.

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

Next, the exposure apparatus U3 shown in FIG. 2 will be described. The exposure device U3, in addition to the driving rollers R4 to R6, the edge position controller EPC3, and the alignment microscopes AM1 and AM2, also includes a mask holding mechanism 11, a substrate supporting mechanism 12, an illumination optical system IL, a projection optical system PL, And lower control device 16. The exposure device U3 guides 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 onto the substrate. The substrate P held by the support mechanism 12.

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

The mask holding mechanism 11 includes a mask holding cylinder (mask holding member) 21 that holds the mask M, and a first driving unit 22 that rotates the mask holding cylinder 21. The mask holding cylinder 21 holds the mask M so that the first axis AX1 of the mask M is the center of rotation. The first driving unit 22 is connected to the lower control device 16 and rotates the photomask holding cylinder 21 with the first axis AX1 as a rotation center.

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

The substrate supporting mechanism 12 includes a substrate supporting cylinder 25 that supports the substrate P with a cylindrical outer peripheral surface and is rotatable, a second driving unit 26 that rotates the substrate supporting cylinder 25, and a pair of air turn bars. ATB1, ATB2, and a pair of guide rollers 27, 28. The substrate supporting cylinder 25 is formed in a cylindrical shape having an outer peripheral surface (peripheral surface) having a curvature radius Rp centered on a 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 a center plane CL. A part of the circumferential surface of the substrate supporting cylinder 25 is a supporting surface P2 that supports the substrate P. In other words, the substrate support cylinder 25 supports the substrate P by winding the substrate P on its support 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 a rotation center.

A pair of air reversing levers ATB1 and ATB2 are provided on the upstream side and the downstream side of the substrate P in the conveying direction via the substrate support cylinder 25, respectively. A pair of air reversing levers 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). A pair of guide rollers 27 and 28 are provided on the upstream side and the downstream side of the substrate P in the conveying direction via a pair of air reversing levers ATB1 and ATB2, respectively. A pair of guide rollers 27 and 28. One of the guide rollers 27 guides the substrate P transferred from the driving roller R4 to the air reversing lever ATB1, and the other of the guide rollers 28 transfers the substrate from the air reversing lever ATB2. P is guided to the driving roller R5.

As described above, the substrate supporting mechanism 12 guides the substrate P transferred from the driving roller R4 to the air reversing lever ATB1 with the guide roller 27, and introduces the substrate P passing through the air reversing lever ATB1 into the substrate supporting cylinder 25. The substrate supporting mechanism 12 rotates the substrate supporting cylinder 25 by the second driving unit 26, and thereby supports the substrate P introduced into the substrate supporting cylinder 25 with the supporting surface P2 of the substrate supporting cylinder 25, and conveys it to the air while turning Rod ATB2. The substrate supporting mechanism 12 guides the substrate P transferred to the air reversing lever ATB2 to the guide roller 28 with the air reversing lever ATB2, and guides the substrate P passing through the guide roller 28 to the driving roller R5.

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

The light source device 13 emits an illumination light beam EL1 which is illuminated by the mask M. The light source device 13 includes a light source 31 and a light guide member 32. The light source 31 is a light source emitting a predetermined wavelength. As the light source 31, for example, a lamp light source such as a mercury lamp, a laser diode, a light emitting diode (LED), or the like can be used. The illumination light emitted from the light source 31 is, for example, far-ultraviolet light (DUV light) such as glow lines (g-line, h-line, i-line, etc.) emitted from a lamp light source, KrF excimer laser light (wavelength 248 nm), ArF excimer laser light (Wavelength 193nm) and so on. The light source 31 here preferably emits an illumination light beam EL1 including a wavelength of i-line (wavelength of 365 nm) or less. As the light source 31 for generating an illumination beam EL1 with a wavelength below the i-line, laser light (wavelength of 355 nm) emitted from a YAG laser (third harmonic laser), and laser light from a YAG laser (fourth harmonic laser) can be used. ) Laser light (wavelength of 266 nm), or laser light (wavelength of 248 nm) emitted from KrF excimer laser.

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 configured by a relay module or the like using an optical fiber or a mirror. When a plurality of light guide members 32 are provided in the illumination optical system IL, the light guide member 32 separates the illumination light beams EL1 from the light source 31 into a plurality of light guides and guides the plurality of illumination light beams EL1 to the plurality of illumination optical systems IL. The light guide member 32, which is the light guide member 32 of the present embodiment, causes the illumination light beam EL1 emitted from the light source 31 to be a light in a predetermined polarization state and enters the polarization beam splitter PBS. The polarizing beam splitter PBS of this embodiment reflects a linearly polarized light beam as S-polarized light, and transmits a linearly polarized light beam as P-polarized light. Therefore, the light source device 13 emits the illumination light beam EL1 that has entered the polarization beam splitter PBS into a linearly polarized light (S-polarized light).

The light source device 13 emits polarized lasers having the same wavelength and phase to the polarizing beam splitter PBS. For example, when the light source device 13 emits polarized light, the polarized light is used 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. Alternatively, for example, the light beam output from the light source 31 may be guided by an optical fiber, and the light output from the optical fiber may be polarized by a polarizing plate. That is, the light source device 13, when guiding a random polarized light beam, can also polarize the random polarized light beam with a polarizing plate, and can also use a polarizing beam splitter PBS to divide into P-biased and S-biased beams to transmit the polarized light The light of the beam splitter PBS is used as a light beam that is incident on the illumination optical system IL of one system, and the light reflected by the polarizing beam splitter PBS is used as a light beam that is incident on the illumination optical system IL of another system. The light source device 13 may also guide a 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 is an exposure apparatus of a so-called multi-lens method. 3 shows a plan view of the illumination region IR on the reticle M held by the reticle holding cylinder 21 viewed from the −Z side (left view of FIG. 3) and a substrate support cylinder viewed from the + Z side. A plan view of the projection area PA on the substrate P supported by 25 (right view in FIG. 3). Symbol Xs in FIG. 3 represents the moving direction (rotation direction) of the mask holding cylinder 21 and the substrate supporting cylinder 25. The multi-lens type exposure device U3 is provided on the mask M (for example, six in the first embodiment). The illumination areas IR1 to IR6 respectively illuminate the illumination light beam EL1, and each illumination light beam EL1 is in each illumination area IR1. The plurality of projection light beams EL2 obtained by the reflection of ~ IR6 are projected and exposed to a plurality of projection areas PA1 to PA6 (for example, six in the first embodiment) on the substrate P.

First, a plurality of illumination areas IR1 to IR6 illuminated by the illumination optical system IL will be described. As shown in FIG. 3, the plurality of illumination areas IR1 to IR6 are arranged on the mask M upstream of the rotation direction via the center plane CL. The first illumination area IR1, the third illumination area IR3, and the fifth illumination area IR5 are arranged on the rotation. A second illumination area IR2, a fourth illumination area IR4, and a 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 an elongated 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 illumination areas IR1 to IR6 of the trapezoid is an area whose short side is located on the side of the central plane CL and whose long side is located 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. The second illumination area IR2, the fourth illumination area IR4, and the sixth illumination area IR6 are also arranged at predetermined intervals 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 region IR3 is arranged between the second illumination region IR2 and the fourth illumination region IR4 in the axial direction. The fourth illumination area IR4 is arranged between the third illumination area IR3 and the fifth illumination area IR5 in the axial direction. The fifth illumination area IR5 is arranged between the fourth illumination area IR4 and the sixth illumination area IR6 in the axial direction. Each of the illumination regions IR1 to IR6 is arranged so that the triangular portions of the hypotenuses of the adjacent trapezoidal illumination regions overlap each other as viewed from the circumferential direction (X direction) of the mask M. In the first embodiment, each of the illumination areas IR1 to IR6 is formed as a trapezoidal area, but it may be formed as a rectangular area.

The photomask M has a pattern forming area A3 in which a photomask pattern is formed, and a pattern non-forming area A4 in which a photomask pattern is not formed. The pattern non-formation area A4 is a non-reflective 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 so as to cover the full width in the Y direction of the pattern forming area A3.

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

Next, each of the illumination optical systems IL1 to IL6 will be described with reference to FIG. 4. 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.

In order to illuminate the illumination area IR (the first illumination area IR1) with uniform illumination, the illumination optical system IL is a Kohler illumination method adapted to convert the illumination light beam EL1 from the light source device 13 into a surface light source image of a plurality of point light sources. . 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 polarizing beam splitter PBS, and a 1/4 wavelength plate 41 in this 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 collimating 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 beam EL1. 55 and a plurality of relay lenses 56 are disposed on the first optical axis BX1. A 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 irradiates the entire surface of the entrance 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 surface on the exit side of the fly-eye lens 52 is arranged on the first optical axis BX1. The fly-eye lens 52 divides the illumination 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 a condenser lens 53 described later.

At this time, the surface of the exit side of the fly-eye lens 52 that generates the point light source image passes through the fly-eye lens 52 through the illumination field diaphragm 55 to various lenses of the first concave mirror 72 of the projection optical system PL described later, and is arranged to be the same as the first concave mirror The pupil plane where the reflecting surface of 72 is optically conjugated. 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 light (illumination light beam EL1) from each point light source of the fly-eye lens 52 through the cylindrical lens 54 and irradiates the illumination field diaphragm 55 so as to be superimposed thereon. In the case of the non-cylindrical lens 54, the main rays of the illumination light beam EL1 reaching the points on the illumination field diaphragm 55 are all parallel to the first optical axis BX1. However, by the action of the cylindrical lens 54, each principal ray of the illumination beam EL1 that illuminates the illumination field diaphragm 55 becomes a telecentric state parallel to each other in the Y direction in FIG. 4 (also parallel to the first optical axis BX1). In the XZ plane, a non-telecentric state in which the inclination with respect to the first optical axis BX1 sequentially differs according to the image height position.

The cylindrical lens 54 is a plano-convex cylindrical lens having a flat entrance side and a convex exit side, and is disposed 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 on the exit side of the cylindrical lens 54 is set parallel to the Y axis in FIG. 4. As a result, the principal rays of the illumination beam EL1 immediately after passing through the cylindrical lens 54 are parallel to each other in the Y direction with the first optical axis BX1, and in the XZ plane toward a point on the first optical axis BX1 (strictly come It is said that a line extending in the Y direction orthogonal to the first optical axis BX1) converges.

The opening portion of the illumination field diaphragm 55 is formed in a trapezoidal shape (rectangular shape) having the same shape as the illumination region IR, and the center of the opening portion of the illumination field diaphragm 55 is arranged on the first optical axis BX1. At this time, the illumination field diaphragm 55 passes through a relay lens (imaging system) 56 between the illumination field diaphragm 55 and the cylindrical surface P1 of the mask M, a polarizing beam splitter PBS, and a quarter-wave plate. 41 and the like are arranged on a surface optically conjugate to the illumination region 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 passes the illumination beam EL1 passing through the opening of the illumination field diaphragm 55 through the polarizing beam splitter PBS and the 1/4 wavelength plate 41 and irradiates the cylindrical surface P1 of the mask M (illumination area IR).

The polarizing beam splitter PBS is disposed between the illumination optical module ILM and the center plane CL. The polarizing beam splitter PBS reflects a linearly polarized light beam that is S-polarized light on a wavefront division surface, and transmits a linearly polarized light beam that is P-polarized light. Here, the illumination light beam EL1 that enters the polarizing beam splitter PBS is a linearly polarized beam that is S-polarized light, and the reflected light (projection beam EL2) from the mask M that enters the polarizing beam splitter PBS passes through a 1/4 wavelength The plate 41 becomes a linearly polarized light beam of P polarized light.

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

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

Here, the illumination optical system IL is a mask for the mask in such a manner that the principal rays of the projection light beam EL2 reflected by the illumination region IR on the surface P1 of the mask M become telecentric regardless of whether in the Y direction or the XZ plane. The illumination area IR of M illuminates the illumination beam EL1. The state will be described with reference to FIG. 5.

FIG. 5 is an exaggerated display of the state of the illumination beam EL1 in the illumination region IR and the projection beam EL2 reflected in the illumination region IR on the XZ plane (the plane perpendicular to the first axis AX1) in the illumination region IR. As shown in FIG. 5, the above-mentioned illumination optical system IL is such that the main ray of the projection light beam EL2 reflected in the illumination region IR of the mask M becomes telecentric (parallel system) so that the illumination region IR of the illumination mask M is irradiated. The main ray of the illumination light 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 beam EL1 are imparted by the cylindrical lens 54 shown in FIG. 4. Specifically, a circle having a radius of 1/2 of the radius Rm of the first axis AX1 and the radius Rm of the surface P1 of the mask M is set at a point Q1 passing through the center point Q1 of the illumination region IR on the surface P1 of the mask M. 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 each principal ray of the illumination light beam EL1 passing through the illumination area IR strikes the intersection point Q2 on the XZ plane. In this way, each principal ray of the projection light beam EL2 reflected in the illumination area IR is 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 exposed by projection optical system PL projection 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 on the substrate P on the upstream side in the conveying direction via the center plane CL. The first projection area PA1, the third projection area PA3, and the fifth projection area PA5 are arranged on 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 is an elongated trapezoidal area having short sides and long sides extending in the width direction (Y direction) of the substrate P. At this time, each of the projection areas PA1 to PA6 of the trapezoid is an area whose short side is located on the center plane CL side and whose long side is located 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. 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. Each of the projection areas PA1 to PA6 is the same as each of the illumination areas IR1 to IR6. When viewed from the conveying direction of the substrate P, the triangular portions of the hypotenuse of the adjacent trapezoidal projection area PA are arranged to overlap. 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-repeating area. The first to sixth projection areas PA1 to PA6 are configured to cover the full width in the Y direction of the exposure area A7 exposed on the substrate P.

Here, in FIG. 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). The distance is set from the center point of an 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 an even number of projection areas PA2 (and PA4, PA6). The perimeters are essentially equal. This is because the projection magnification of each of the projection optical systems PL1 to PL6 is set to equal magnification (× 1).

The projection optical system PL is provided with a plurality of projection areas PA1 to PA6 (for example, six in the first embodiment). In a plurality of projection optical systems (splitting projection optical systems) PL1 to PL6, a plurality of projection light beams EL2 reflected from the plurality of illumination areas IR1 to IR6 are incident respectively. Each projection optical system PL1 to PL6 guides each projection light beam EL2 reflected by the mask M to each projection area PA1 to PA6. 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. 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 in the illumination areas IR2 to IR6 is guided to the second to sixth projection areas PA2 to PA6. A plurality of projection optical systems PL1 to PL6 are arranged with the first projection optical system PL1, the third projection optical system PL1, the third projection area PA1, the third projection area PA1, the third projection area PA5, and the fifth projection area (left side in FIG. 2) across the center plane CL. 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 predetermined intervals in the Y direction. In addition, a plurality of projection optical systems PL1 to PL6 are provided with a second projection optical system PL2 on the side (right side of FIG. 2) where the second, fourth, and sixth projection areas PA2, PA4, and PA6 are disposed across the center plane CL. 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 predetermined intervals in the Y direction. At this time, the second projection optical system PL2 is arranged between the first projection optical system PL1 and the third projection optical system PL3 in the axial direction. Similarly, the third projection optical system PL3, the fourth projection optical system PL4, and the fifth projection optical system PL5 are arranged 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. The first projection optical system PL1, the third projection optical system PL3, and the fifth projection optical system PL5 are symmetrical to the second projection optical system PL2, the fourth projection optical system PL4, and the sixth projection optical system PL6 when viewed from the Y direction. Configuration.

Next, a detailed configuration of each of the projection optical systems PL1 to PL6 will be described with reference to FIG. 4. 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 an image of a mask pattern in an illumination region IR (first illumination region IR1) on the mask M onto a projection region PA on a substrate P. The projection optical system PL includes the 1/4 wavelength plate 41, the polarizing 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 wavelength plate 41 and the polarizing beam splitter PBS are used in combination with the illumination optics IL. In other words, the illumination optical system IL and the projection optical system PL share a quarter-wavelength plate 41 and a polarizing 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 1/4 wavelength plate 41, passes through the polarizing beam splitter PBS, becomes a telecentric imaging beam, and enters the projection optical system PL ( Projection optical module PLM).

The projection optical module PLM is arranged corresponding to the illumination optical module ILM. That is, the projection optical module PLM of the first projection optical system PL1 is a projected image of the mask pattern on the first illumination area IR1 illuminated by the illumination optical module ILM of the first illumination optical system IL1 onto the substrate P. 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 areas IR2 of the illumination optical modules ILM of the second to sixth illumination optical systems IL2 to IL6. The images of the mask pattern of ~ IR6 are 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 includes a first optical system 61 that forms an image of a mask pattern of the illumination area IR on the intermediate image plane P7 and at least a part of the intermediate image that is imaged by the first optical system 61. A second optical system 62 re-imaged on the projection area PA of the substrate P, and a projection field diaphragm 63 disposed on the intermediate image plane P7 forming the intermediate image. The projection optical module PLM includes a focus correction optical member 64, an image shift optical member 65, a magnification correction optical member 66, 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, telecentric refracting and refracting optical systems in which a Dyson system is deformed. The first optical system 61 has an optical axis (hereinafter, referred to as a second optical axis BX2) 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 ridge having a first reflecting surface P3 and a second reflecting surface P4. The first reflection surface P3 is a surface that reflects the projection light beam EL2 from the polarizing beam splitter PBS, and makes the reflected projection light beam EL2 pass through the first lens group 71 and enter the first concave mirror 72. The second reflecting surface P4 is a surface that allows the projection light beam EL2 reflected by the first concave mirror 72 to pass through the first lens group 71 and is incident thereon, 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 disposed on a pupil surface where a plurality of point light sources generated by the fly-eye lens 52 pass through the illumination field diaphragm 55 to the various lenses of the first concave mirror 72 to form an image.

The projection light beam EL2 from the polarizing beam splitter PBS is reflected by the first reflecting surface P3 of the first deflection member 70 and 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 and passes through a field of view in the lower half of the first lens group 71 to enter the second reflecting surface P4 of the first deflection member 70. The projection light beam EL2 incident on the second reflection surface P4 is reflected on the second reflection surface P4, and is incident on the projection field diaphragm 63 by the focus correction optical member 64 and the image shift optical member 65.

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 made similar to the shape (trapezoidal shape) of the projection area PA, the projection field diaphragm 63 can be omitted. When the opening shape of the illumination field diaphragm 55 is a rectangle including the projection area PA, it is necessary to use a projection field diaphragm 63 that defines a trapezoidal projection area PA.

The second optical system 62 has the same configuration as the first optical system 61, and is disposed symmetrically with the first optical system 61 via the intermediate image plane P7. The second optical system 62 has an optical axis (hereinafter, referred to as a third optical axis BX3) substantially orthogonal to the center plane CL and is 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 deflecting member 80 includes a third reflecting surface P5 and a fourth reflecting surface P6. The third reflecting surface P5 is a surface that reflects the projection light beam EL2 from the projection field diaphragm 63 and makes the reflected projection light beam EL2 pass through the second lens group 81 and enter the second concave mirror 82. The fourth reflection surface P6 is a surface that allows the projection light beam EL2 reflected by the second concave mirror 82 to pass through the second lens group 81 and reflects the incident projection light beam EL2 toward the projection area PA. The second lens group 81 includes various lenses, and the optical axes of the various lenses are arranged on the third optical axis BX3. The second concave mirror 82 is disposed on a pupil surface where a plurality of point light source images imaged on the first concave mirror 72 pass through the projection field diaphragm 63 to various lenses of the second concave mirror 82 and form an image.

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

The focus correction optical member 64 is disposed 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 correcting optical member 64 is, for example, a pair of two wedge-shaped ridges inverted (inverted in the X direction in FIG. 4) superimposed into a parallel flat plate that is transparent as a whole. The thickness of the parallel flat plate can be changed by sliding the pair of slugs toward the slope without changing the interval between the faces facing each other. Accordingly, the effective optical path length of the first optical system 61 can be fine-tuned, and the focusing state of the mask pattern image formed on the intermediate image plane P7 and the projection area PA can be fine-tuned.

The image shift optical member 65 is disposed between the first deflection member 70 and the projection field stop 63. The image shift optical member 65 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 a 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 amounts of the two parallel flat glass plates, the images 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 magnification correction optical member 66 is disposed between the second deflection member 70 and the substrate P. The magnification correction optical member 66 is constituted by, for example, arranging three concave lenses, convex lenses, and concave lenses coaxially at a predetermined interval, and fixing the front and rear concave lenses, and the convex lenses in between can be moved in the direction of the optical axis (principal light). According to this, the image of the mask pattern formed in the projection area PA can be enlarged or reduced isotropically while maintaining the telecentric imaging state. In addition, the optical axes of the three lens groups constituting the magnification correction optical member 66 are inclined in the XZ plane and parallel to the main ray of the projection light beam EL2.

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

The polarization adjustment mechanism 68 is, for example, an actuator (not shown) that rotates the 1/4 wavelength plate 41 about an axis orthogonal to the plate surface to adjust the polarization direction. 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 1/4 wavelength plate 41.

In the projection optical system PL configured in this manner, each of the principal rays of the projection light beam EL2 from the mask M is emitted from the surface P1 of the mask M in the illumination area IR in a telecentric state, and passes through the 1/4 wavelength plate 41 and polarized light. The beam splitter PBS enters the first optical system 61. The projection light beam EL2 incident on the first optical system 61 is reflected by the first reflecting surface (planar mirror) P3 of the first deflection member 70 of the first optical system 61 and is reflected by the first lens group 71 and the first concave mirror 72. The projection light beam EL2 reflected by the first concave mirror 72 passes through the first lens group 71 again and is reflected by the second reflecting surface (planar mirror) P4 of the first deflection member 70, and passes through the focus correction optical member 64 and the image shifting optical member 65. Into the projection field diaphragm 63. The projection light beam EL2 that has passed through the projection field diaphragm 63 is reflected by the third reflecting surface (planar mirror) P5 of the second deflection member 80 of the second optical system 62 and is reflected by the second concave mirror 82 through the second lens group 81. The projection light beam EL2 reflected by the second concave mirror 82 passes through the second lens group 81 again, is reflected on the fourth reflecting surface (planar mirror) P6 of the second deflection member 80, and enters the optical element 66 for magnification correction. The projection light beam EL2 emitted from the magnification correction optical member 66 enters the projection area PA on the substrate P, and the image of the mask pattern appearing in the illumination area IR is projected onto the projection area PA at equal magnification (× 1).

<Relationship between projection image surface of mask pattern and exposure surface of substrate>

Next, the relationship between the projection image surface of the mask pattern 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 a relationship between a projection image surface of a pattern of a photomask and an exposure surface of a substrate. FIG. 6B is an explanatory diagram schematically showing a change in a focus position (a defocus amount) of a pattern image projected in a projection area.

The exposure device U3 forms the projection image plane Sm of the pattern of the mask M by projecting the light beam EL2 with the projection optical system PL. The projection image surface Sm is a position where the pattern of the mask M is imaged, and is a position for optimal focusing. Here, as described above, the mask M is arranged on a curved surface (curve in the ZX plane) with a radius of curvature Rm. As a result, the projection image plane Sm is also a curved surface with a radius of curvature Rm. In the exposure device U3, the surface of the substrate P is an exposure surface Sp. Here, the exposure surface Sp is the surface of the substrate P. The substrate P is held in 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 curvature radius Rm. The projection image surface Sm and the exposure surface Sp are axes that are curved surfaces in a direction orthogonal to the scanning exposure direction.

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

The actual exposure surface Spa intersects at two positions FC1 and FC2 different from the projection image surface Sm in the scanning exposure direction. In addition, the exposure device U3 can finely adjust 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 adjust the focus correction optics. The component 64 changes the position of the normal direction (focus adjustment direction) of the actual exposure surface Spa with respect to the projection image surface Sm.

The projection image plane Sm and the actual exposure plane Spa are set to intersect at two different positions FC1 and FC2 within the exposure width A in 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 an optimal 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 surface Sm) of the projected pattern image behind the actual exposure surface Spa, and the focus state is at the position FC1. The area further outside from the position FC2 becomes the best focus surface (projection image surface Sm) of the pattern image to be projected in front of the actual focus surface before the actual exposure surface Spa.

That is, when the surface of the substrate P is moved from one end portion As of the exposure width A to the other end portion Ae along the actual exposure surface Spa, the pattern image on the substrate P is at the end portion As 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 optimal focusing state at the position FC1, the defocus amount increases in the opposite direction, and the center deflection amount FC3 becomes the maximum defocus amount at the exposure width A. Taking the center position FC3 of the exposure width A as the turning point, the amount of defocus is reduced thereafter, and the pattern image is again exposed on the substrate P in the optimal focus state at the position FC2. After passing the optimal focus state at the position FC2, the defocus amount increases again, and at the other end Ae, the exposure of the pattern image ends. As described above, in the area between the position FC1 and the position FC2 and the area further outside the position between the position FC1 and the position FC2, the direction of the defocus, that is, the correspondence of the defocus is different.

As described above, while the substrate P moves from the end portion As to the end portion Ae of the exposure width A of the projection area PA at a certain peripheral speed, each point in the pattern image projected on the substrate P is shown in FIG. 6B Display, 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) While continuously changing, the substrate P is exposed. The zero of the focus position (or defocus amount) of the vertical axis in FIG. 6B is an optimal focus state where the difference (Sm-Spa) between the position of the projection image plane Sm and the position of the actual exposure plane Spa is zero. In addition, although the horizontal axis of FIG. 6B shows the linear position of the exposure width A, it may be a position in the circumferential direction of the outer peripheral surface of the substrate support cylinder 25.

The amount of defocus in the focus state (positive direction) before the ends 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 (resolution, Depth of focus), exposure width A of the projection area PA, minimum size of the mask pattern to be projected, radius of curvature Rm of the surface P1 (projection image surface Sm) of the mask M, outer peripheral surface of the substrate supporting cylinder 25 (substrate P The radius of curvature Rp of the exposure surface Spa) above determines the preferred range. Although specific numerical examples are described later, as described above, since the focus state is continuously changed during the scanning exposure that covers the exposure width A, it is possible to enlarge particularly thin lines or discrete contact holes (through holes) in the mask pattern. ) And other isolated patterns.

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

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

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

In general, the resolution R and the depth of focus DOF of the projection optical system PL are expressed by the following equations.

R = k1‧λ / NA (0 <k1 ≦ 1)

DOF = k2‧λ / NA ² (0 <k2 ≦ 1)

Here, k1, k2 are coefficients that may change due to exposure conditions, photosensitive materials (photoresist, etc.), or development or film formation after exposure, but the k1 factor of the resolution R is approximately 0.4 ≦ k1 ≦ 0.8 In this range, the k2 factor of the depth of focus DOF can be expressed as approximately k2 ≒ 1.

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

Here, ΔRm, ΔRp are based on the curvature radius Rm of the projection image surface Sm (the surface P1 of the mask M), the curvature radius Rp of the surface of the substrate P (the actual exposure surface Spa), and the exposure width A, respectively, according to the following formulas Find it out.

It is clear from this formula that ΔRm and ΔRp respectively represent ΔFm and ΔFp shown in FIG. 6A. It is preferable that the above-mentioned relational expression 1 further satisfies DOF <(ΔRm + ΔRp). In the exposure apparatus U3 of this embodiment, although the exposure width A, the curvature radius Rm, and Rp are determined in such a manner as to satisfy 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. In this regard, the second embodiment will be described in detail.

In this embodiment, the variation range of the defocus amount in the exposure width A, that is, the defocus amount in the positive direction of the ends As and Ae shown in FIG. 6B and the center position FC3 at the exposure width A When the difference in the defocus amount in the negative direction is set to ΔDA, from 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, it is possible to maintain the quality of various patterns (line width accuracy, position accuracy, overlap accuracy, etc.) for the display panel formed on the substrate P, and improve productivity. In this regard, 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 in the scanning exposure direction by setting the projection image plane Sm of the pattern of the mask M and the actual exposure surface Spa of the substrate P in the scanning exposure direction to expose the projection area PA. The center position FC3 of the width A is linearly symmetrical as the axis changes (left-right symmetry in FIG. 6B).

Moreover, in this embodiment, as shown in FIG. 6B, the interval from the end As to the position FC1 and the interval from the position FC2 to the end Ae within the exposure width A of the projection area PA may be adjusted. The value (absolute value) after integration of the defocus amount in the positive direction is compared with the value (absolute value) after the integration of the defocus amount in the negative direction between the 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.

The exposure device U3 of this embodiment is configured by arranging a plurality of projection optical modules PLM in at least two rows in the scanning exposure direction and in a Y direction orthogonal to the scanning exposure direction, so that the projection areas of adjacent projection optical modules PLM are The end portions (triangular portions) of the PA are overlapped with each other to expose the pattern of the mask M in the Y direction. Thereby, it is possible to suppress the occurrence of band-like unevenness caused by the contrast or exposure of the pattern images of the joints (overlapping areas) between the two projection areas PA adjacent to each other in the Y direction. In this embodiment, in addition to this, the scanning exposure direction in the projection area PA on the actual exposure surface Spa (the surface of the substrate P) can form two optimal focus positions (position FC1, position FC2). The mode sets the positional relationship between the projected image surface Sm and the actual exposure surface Spa, so the change in image contrast caused by the dynamic defocus caused by the slight change in the positional relationship between the projected image surface Sm and the actual exposure surface Spa during scanning exposure can be reduced. Therefore, it is also possible to reduce the difference in image contrast generated in the overlapping area between the adjacent projection areas PA, and it is possible to manufacture a high-quality flexible display panel in which the joint portion is not obvious.

As shown in this embodiment, when each projection area PA of the plurality of projection optical modules PLM is arranged in the Y direction orthogonal to the scan exposure direction (X direction), the width of the scan exposure direction of each projection area PA 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 the two projection areas PA adjacent to each other in the Y direction partially overlap (the overlapping area of the triangle) is also set to the total value of the cumulative value in one triangular area and the cumulative value in the other triangular area. The accumulated values of the non-overlapping areas are the same. This makes it possible to suppress a change in the exposure amount in a direction orthogonal to the scanning exposure direction.

In addition, the exposure device U3 has a projection surface Sm and an exposure surface Sp (actual exposure surface Spa) as 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 columns with odd and even numbers are arranged.) Since the relationship between the projection image surface Sm and the exposure surface Sp (actual exposure surface Spa) is the same in each projection optical module PLM, these relationships can be adjusted together. Like the usual multi-lens projection exposure device, when the projection surface and the exposure surface are flat, for example, in the projection area of an odd number of projection optical modules, if the exposure surface (the surface of a flat substrate) is enlarged to increase the focal depth ) Is tilted relative to the projection image plane, a large defocus is difficult to be tolerated in the projection area of an even number of projection optical modules. In contrast, as shown in this embodiment, the projection image surface Sm and the exposure surface Sp (actual exposure surface Spa) are made into a cylindrical surface, and two projection optical modules PLM arranged in the scanning exposure direction are projected on each projection. The focus adjustment of the area PA can pass through the interval in the Z direction 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, or each projection optical module PLM. The internal magnification correction is easily achieved by adjusting the optical member 66. Thereby, it is possible to suppress a change in contrast of an image with respect to defocus with a simple device configuration. Since the image contrast can be suppressed and the exposure width of the scanning exposure area can be increased, the production efficiency is also improved.

[Second Embodiment]

Next, an exposure apparatus U3a of the second embodiment will be described with reference to Fig. 7. In addition, in order to avoid repetitive descriptions, portions different from those of the first embodiment will be described, and the same constituent elements as those of the first embodiment will be given the same reference numerals as those of the first embodiment. FIG. 7 is a diagram showing the overall configuration of an exposure apparatus (substrate processing apparatus) according to a second embodiment. Although the exposure device U3 of the first embodiment is configured to hold the substrate P passing through the projection area by a cylindrical substrate support cylinder 25, the exposure device U3a of the second embodiment is configured to hold the substrate P to support the substrate P The planar and movable substrate support mechanism 12a is configured.

In the exposure apparatus U3a of the second embodiment, the substrate supporting 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. (Illustration omitted). Therefore, the substrate P may be a flexible glass substrate (a resin mold such as PET and PEN, an extremely thin curved peeling surface, a thin metal foil, etc.), or a glass substrate with almost no bending.

Since the support surface P2 of the substrate P in FIG. 7 is a plane (curvature radius ∞) substantially parallel to the XY plane, it reflects from the mask M and passes through the projection optical module PLM and is projected onto the projection light beams EL2 and XY planes of the substrate P.成 Vertical.

In the second embodiment, as in the previous FIG. 2, when viewed in the XZ plane, from the center point of the illumination area IR1 (and IR3 and IR5) on the cylindrical mask M to the illumination area IR2 ( And IR4, IR6) and the perimeter of the center point of the projection area PA1 (and PA3, PA5) on the substrate P running 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.

Similarly to the exposure device U3a in FIG. 7, the lower control device 16 controls the moving device (such as a linear motor for scanning exposure or an actuator for micro-movement) of the substrate supporting mechanism 12 in synchronization with the rotation of the mask holding cylinder 21 Ground driving substrate stage 102.

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

The exposure device U3a images the projection light beam EL2 by the projection optical system PL to form a projection image surface Sm1 of the pattern of the mask M. The projection image surface Sm1 is a surface that images the cylindrical mask pattern surface of the mask M in an optimal focus state, and is a cylindrical surface. Here, the illumination area IR on the mask M is a part of the curved surface (the arc in the XZ plane) of the curvature radius Rm1 as described above, so the projection image plane Sm1 is also the curved surface (in the XZ plane) of the curvature radius Rm1. Is an arc). The planar surface of the substrate P on which the image of the mask pattern is projected is the exposure surface Sp1 (curvature radius ∞). Therefore, as shown in FIG. 8, the projection image planes Sm1 (left side) of the odd projection areas PA and the projection image planes Sm1 (right side) of the even projection areas PA are both curved into a cylindrical shape in the scanning exposure direction (X direction). In the same manner as that shown in FIG. 6A, the projection area PA has a difference in surface position (focusing) between the focus position at both ends and the focus position at the center of the exposure width A in the exposure width A of the scanning exposure direction. Change width) ΔFm. Here, during scanning exposure, the surface of the substrate P is disposed on the actual exposure surface Spa1. Since the exposure surface Sp1 and the actual exposure surface Spa1 are planes, within the exposure width A of the projection area PA in the scanning exposure direction, the change amount of the surface position in the Z direction is 0. The actual exposure surface Spa1 is set so that two different positions FC1 and FC2 separated in the scanning exposure direction on the projection image plane Sm1 intersect. That is, the exposure device U3 can adjust either the optical member 66 for magnification correction in the projection optical system PL or the like, or move either of the mask holding mechanism 11 (first axis AX1) and the substrate supporting 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 a position at which the mask pattern image in the projection image plane Sm1 is exposed at an optimal focus state.

Therefore, in this embodiment, similarly, by the rotational movement of 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. Furthermore, it is possible to suppress the contrast change of the image with respect to the substantial focus. As described above, even if the exposure surface Sp1 (the actual exposure surface Spa1) is flat, the projection image surface Sm1 can be formed into a cylindrical surface curved in the scanning exposure direction, and can be obtained without tilting the substrate P. The effect of increasing the depth of focus of the mask pattern image exposed on the substrate P in appearance and suppressing the change in image contrast can be suppressed. Such an effect can also be obtained in a case where a pattern image from a normal flat mask is projected and exposed on the surface (exposed surface) of a substrate supported in a cylindrical shape.

In addition, in the case of this embodiment, since the surface position difference (focus change width) ΔFm shown in FIG. 8 is the same as ΔRm of the previous formula 2, it can be calculated as Find it out. Therefore, based on Equation 2, after trying various simulations such as the projection state or imaging characteristics in the exposure device U3a of FIG. 7, the results shown in FIGS. 9 to 17 can be obtained.

In addition, in this simulation, if the radius Rm of the surface P1 (projection surface Sm1) of the cylindrical mask M is set to 250 mm (diameter ψ 500 mm), the wavelength λ of the illumination light beam EL1 for exposure is set to i. Line (365nm), the projection optical system PL is set to an ideal projection system with a numerical aperture NA equal to 0.0875, and the exposure surface Sp1 (the actual exposure surface Spa1) is a plane with a radius of curvature ∞, which depends on the depth of focus of the process, k2 The factor is set to 1.0, and the depth of focus DOF of such a projection optical system PL is approximately 48 μm in width (based on λ / NA ²⁾ (a range of approximately ± 24 μm relative to the optimal focusing surface). In addition, in the following simulations, for convenience of explanation, the depth of focus DOF may be set to a width of 40 μm (relatively optimal focusing surface is in a range of approximately ± 20 μm).

Further, 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 optimal focus position. The defocus amount of the projection image plane Sm1 at the origin (zero point). The graph of FIG. 9 is also a diagram obtained by plotting the surface position difference ΔRm obtained by setting the exposure width A to 20 mm and changing the coordinate position of the width A from -10 mm to +10 mm in the previous formula 2. 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.

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

First, under the above conditions, the point image intensity distribution I (z) of the defocus amount generated when the defocus characteristic Cm of the arc-shaped change in the exposure width A is distinguished in units of focal depth DOF is shown in FIG. 10 Show it out. The point image intensity distribution is obtained by the formula I (z) = [sin (ΔDz) / (ΔDz)] ² × I ₀ and ΔDz = (π / 2 / λ) × NA ² × z described above.

Secondly, for the assumption that the average of the defocus amount is adjusted to become the best focus, the point image intensity distribution in the arc width within the exposure width A is changed to various values such as 0, 1 × DOF, 2 × DOF, 3 × DOF, 4 × DOF. In addition, in the case where the defocus width of the arc-shaped change in the exposure width A is various, the point image intensity distribution when the defocus amount is defocused from its position is calculated using this defocus amount and its slit width as a reference. In this way, the relationship between the point image intensity distribution and the defocus when the defocus width of the arc-shaped change in each exposure width A uniquely determined by the calculated exposure width A is aggregated. Specifically, it is aimed at setting the defocus width of the arc-shaped change in the exposure width in the exposure device U3a to 0, 0.5 × DOF, 1 × DOF, 1.5 × DOF, 2 × DOF, 2.5 × DOF, 3 × DOF For each of the cases of 3.5 × DOF and 4 × DOF, the relationship between the point image intensity distribution and the focus error and defocus assumed during exposure is calculated.

Secondly, for assuming that the average of the defocus amount is adjusted to become the best focus, the defocus characteristic Cm of the point image intensity distribution in a circular arc shape within the exposure width A is set to various values such as 0,1 × DOF, 2 × DOF, 3 × DOF, 4 × DOF. In addition, for various cases where the defocus characteristics Cm having an arc-shaped change in the exposure width A are various, the point image intensity distribution when the defocus amount and its slit width are used as a reference to calculate the defocus from the position is calculated. In this way, the relationship between the point image intensity distribution and the defocus at the respective defocus characteristics Cm uniquely determined by the calculated exposure width A is aggregated. Specifically, it is set to 0 × DOF, 0.5 × DOF, 1 × DOF, 1.5 × DOF, 2 × DOF, 2.5 × DOF for the defocus characteristic Cm shown in FIG. 9 which is set on the simulation as the exposure device U3a. , 3 × DOF, 3.5 × DOF, 4 × DOF, calculate the point image intensity distribution and the focus error assumed during exposure (from the set position relationship between the set projection image plane Sm1 and the surface of the substrate P Offset). This corresponds to the graph of FIG. 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, the exposure device U3a projects the projection beam EL2 on the substrate P by rotating the cylindrical mask pattern surface, that is, the projection image surface Sm, so the focus error assumed during exposure is performed twice. Variety. Therefore, the state of the point image is slightly different between the positive side and the negative side of the defocus. In this embodiment, the position where the point intensity at the position where the defocus is +40 μm and the point intensity at the position -40 μm are symmetrical is set as the optimal focus. As shown in the graph of FIG. 10, the larger the amplitude due to rotation, that is, as the defocus width in the exposure area becomes larger along the defocus characteristic Cm as shown in FIG. 9, the point image at the best focus The intensity becomes lower, and the change of the point image intensity when defocusing becomes smaller.

Next, calculate the point image intensity change in each case where the defocus characteristic Cm that changes in a circular arc shape 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 difference in point image intensity changes between two points where the characteristic Cm differs by 0.5DOF. The calculation result is shown in FIG. 11. The vertical axis in FIG. 11 represents the difference between the changes in the intensity of the two point images, and the horizontal axis represents the object for which the difference is obtained 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 a difference when the defocus characteristic Cm is changed by 0 × DOF and when it is changed by 0.5 × DOF. According to the simulation result of FIG. 11, the difference between the point image intensity changes from a state where the defocus characteristic Cm has changed by 0.5 × DOF amount to a state where the defocus characteristic Cm has changed by 1 × DOF amount, and the defocus characteristic Cm has changed by 2.5 When the state of the × DOF amount is changed to the state of the 3 × DOF amount, the overall difference is large. That is, in the range of 0.5 × DOF to 3 × DOF, the change of the point image intensity is more gentle than the change of the defocus amount. Therefore, according to the defocus amount of the defocus characteristic Cm, the effect is high when the amplitude is set to 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 formed as an image on the photoresist may vary depending on the resist used or the like. Different, but according to experiments, when the k1 factor of the resolution is about 0.5, as long as the point image intensity is approximately 0.6 or more, an image can be formed. Here, if the focus error estimated as the exposure device is set to the defocus width of the definition formula λ / NA ² to the depth of focus DOF (± 24 μm in this embodiment), The defocus amplitude, that is, the defocus width is set to 2.5 × DOF, that is, the image of the mask pattern can be formed well with a small change in image intensity.

Next, various calculations are performed on the field stage where the mask pattern to be projected is an L / S (line and space) pattern. Here, the range of the focal depth definition formula is set as a range of the focal depth definition formula, that is, in the present embodiment, it is ± 24 μm. The L / S (line and space) pattern is a pattern in which a plurality of linear patterns having 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 varies depending on the lighting conditions, in this embodiment, the lighting numerical aperture σ, which is the lighting condition of the lighting optical system IL, is set to 0.7.

First, when the defocus characteristic Cm shown in FIG. 9 is changed into various kinds, that is, as described 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 the unit is changed by 0.5DOF, 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 -24 μm to calculate the light intensity distribution of the defocused L / S pattern.

Based on the calculation results, the calculated changes in the contrast between the optimal focus state and the defocus state of DOF / 2 are plotted, and the graph after drawing them is shown in FIG. 12. The horizontal axis in FIG. 12 represents the defocus width caused by the defocus characteristic Cm that changes in an arc shape within the exposure width A. The horizontal axis represents contrast. Set the contrast change of the best focus state to 0 μm (BestF). The contrast change in the defocus state is set to ± 24 μmDef. In addition, according to the results shown in FIG. 12, the ratio of the best focus state comparison [0μm (BestF)] to the DOF / 2 defocus state comparison [± 24μmDef], which is [0μm (BestF)] / [± 24 μmDef] The calculated results are shown in FIG. 13. In Fig. 13, the horizontal axis is the defocus width caused by the defocus characteristic Cm that changes in an arc shape within the exposure width A, and the horizontal axis is the comparison.

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

As shown in Figure 14, in the case of the L / S pattern to be projected, the change in line width (change in CD value) is smaller than the change in defocus amplitude in the exposure area. As shown in Figure 12, the comparison Significant changes. However, as shown in FIG. 13, it can be seen that as the amplitude of the defocus becomes larger, the ratio of the contrast in the best focus state to the contrast in the defocus state of ± 24 μm 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 dispersion caused by increasing the defocus characteristic Cm that changes in an arc shape within the exposure width A is increased. The focal width can make the contrast ratio close to 1, reducing the difference between the contrast of the image in the best focus state and the contrast of the image in the defocus state. With this, in the case of the cylindrical mask M (the cylindrical projection image surface Sm1), it is possible to suppress the change of the contrast at the best focus and the contrast at the time of defocus only by rotating the movement. Scanner exposure with a smaller width to suppress the variation of the line width of the pattern being exposed, and increase the variation margin of the projection image surface Sm1 and the surface of the substrate P in the focus direction (the diameter direction of the cylindrical surface).

Next, various calculations are performed when the pattern of the photomask is an isolated line pattern. Here, the range of the focal depth definition formula is set as a range of the focal depth definition formula, that is, in the present embodiment, it is ± 24 μm. An isolated line pattern is a linear pattern with a line width of 2.5 μm. Furthermore, since the imaging state varies depending on the lighting conditions, the illumination numerical aperture σ, which is the lighting condition, is set to 0.7.

As with the previous simulation of the L / S pattern, first, when the defocus characteristic Cm shown in FIG. 9 is changed into various kinds, that is, as described above, 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 defocus state of DOF / 2, that is, the light intensity distribution of the isolated line pattern in the defocused state is calculated at +24 μm or -24 μm. Based on the calculation results, the change characteristics of the image contrast with respect to the change in the defocus width of each 0.5 DOF as shown in FIG. 15 are obtained.

The horizontal axis of FIG. 15 represents the defocus width generated by the defocus characteristic Cm that changes in an arc shape within the exposure width A, and the horizontal axis represents the contrast of the isolated line pattern image. According to the results shown in FIG. 15, similar to the previous FIG. 13, the ratio of the best focus state [0 μm (BestF)] to the DOF / 2 defocus state [± 24 μmDef], that is, [0 μm The result after (BestF)] / [± 24 μmDef] calculation is shown in FIG. 16. In FIG. 16, the horizontal axis is the defocus width generated by the defocus characteristic Cm that changes in an arc shape within the exposure width A, and the horizontal axis is the contrast ratio.

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

Therefore, by setting the defocus width of the arc-shaped defocus characteristic Cm within the exposure width A to a larger 2.5 × DOF or 3 × DOF, even if the set focus position is changed, 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 plane Sm1 and the surface of the substrate P in the focus direction is changed for various reasons during exposure, it is possible to suppress the change in line width with respect to the focus variation, and to keep the The quality of a display panel or an electronic component sequentially manufactured on a substrate P. In addition, it can be seen that an isolated line with a line width of 2.5 μm at the time of optimal focusing and a cut level of 2.5 μm will increase the defocus width caused by increasing the defocus characteristic Cm that changes in an arc shape within the exposure width A. As the value becomes larger, as a result, the change in line width becomes smaller with respect to defocus.

In addition, using the previous FIG. 14 and FIG. 17, comparing the difference in cutting levels due to the difference in patterns, it can be seen that if the defocus width Cm resulting from the arc-shaped change in the exposure width A is set to 2.25 × DOF, compared with the L / S pattern and the isolated line pattern, have substantially the same cutting level (light intensity). Therefore, by setting the defocus width due to the defocus characteristic Cm to a range of 2.25 × DOF, even in the case of a mask pattern in which an L / S pattern and an isolated line pattern are mixed, a high-quality substrate can be manufactured. Therefore, it is not necessary to consider the line width correction (OPC, line width offset) of the mask pattern, which is necessary in the case where the cut level of the L / S pattern and the isolated line pattern are not the same, so that the two can coexist. In addition, since it is not necessary to remake a photomask for line width correction (OPC, line width offset) or to manufacture a plurality of photomasks for adjustment, manufacturing steps and costs can be reduced. In addition, by setting the line width offset, changing the line width of a part of the mask pattern can also prevent the occurrence of undesirable situations such as narrowing the focal depth on the part.

[Third Embodiment]

Next, an exposure apparatus U3b according to the third embodiment will be described with reference to Fig. 18. In addition, in order to avoid repetitive descriptions, only parts different from those in the second embodiment will be described, and the same constituent elements as those in the second embodiment will be given the same reference numerals as those in the second embodiment. FIG. 18 is a diagram showing the overall configuration of an exposure apparatus (substrate processing apparatus) according to a third embodiment. Although the exposure device U3 of the second embodiment has a configuration of a reflective mask that reflects the light of the photomask into a projection beam, the exposure device U3b of the third embodiment uses the light transmitted through the mask to become a transmissive light of the 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 that holds the mask MA, a guide roller 93 that supports the mask holding cylinder 21a, and a driving roller that drives the mask holding cylinder 21a. 94 、 and drive unit 96.

The mask holding cylinder 21a forms a mask surface on which the illumination area IR on the mask MA is arranged. In the present embodiment, the mask surface includes a surface (hereinafter referred to as a cylindrical surface) that rotates a line segment (general line) about 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 or a cylindrical outer peripheral surface. The mask holding cylinder 21a is made of, for example, glass, quartz, or the like, and has a cylindrical shape having a certain thickness. The 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 shape having a constant radius of curvature Rm from the center line. The portion of the mask holding cylinder 21a that overlaps the pattern of the mask MA when viewed from the radial direction of the mask holding cylinder 21a, for example, the central portion of the mask holding cylinder 21a other than both ends in the Y-axis direction of the mask holds the illumination beam EL1. With light transmission.

The photomask MA is, for example, a transmission-type flat sheet photomask formed with a light-shielding layer such as chromium on one side of a long, ultra-thin glass plate (for example, a thickness of 100 to 500 μm) with excellent flatness, so that it can follow the light The outer peripheral surface of the cover holding cylinder 21a is curved, and is used while being wound (attached) to the outer peripheral surface. The photomask MA has a patterned non-formed region where no pattern is formed, and the patterned non-formed region is mounted on the mask holding cylinder 21a. The mask MA is detachably attached to the mask holding cylinder 21a. The photomask MA is the same as the photomask M of the first embodiment. Instead of the mask holding cylinder 21a wound around the transparent cylindrical base material, the mask MA can be held round by the transparent cylindrical base material. A mask pattern formed by forming a light-shielding layer such as chromium is directly drawn on the outer peripheral surface of the cylinder 21a for integration. In this case, the photomask holding cylinder 21a also functions as a photomask holding member.

The guide roller 93 and the driving roller 94 extend in a Y-axis direction that is parallel to the center axis of the mask holding cylinder 21a. The guide roller 93 and the driving roller 94 are provided so as to be rotatable about an axis parallel to the central axis. The outer diameter of the guide roller 93 and the drive roller 94 in the axial direction is larger than that of other portions, and this end is externally connected to the mask holding cylinder 21a. As described above, the guide roller 93 and the driving roller 94 are provided so as not to contact the mask MA held by the mask holding cylinder 21a. The driving roller 94 is connected to the driving portion 96. The driving roller 94 transmits the torque supplied from the driving portion 96 to the photomask holding cylinder 21a to rotate the photomask holding cylinder 21a around the central axis.

Moreover, although the mask holding mechanism 11a is provided with one guide roller 93, the number is not limited, and may be two or more. Similarly, although the mask holding mechanism 11a includes one driving roller 94, the number is not limited, and may be two or more. At least one of the guide roller 93 and the driving roller 94 may be disposed inside the photomask holding cylinder 21a, and may be internally connected to the photomask holding cylinder 21a. The portion of the mask holding cylinder 21a that does not overlap with the pattern of the mask MA when viewed from the radial direction of the mask holding cylinder 21a (both ends in the Y-axis direction) can also have transparency to the illumination light beam EL1. It may not have translucency. One or both of the guide roller 93 and the drive roller 94 may be, for example, a truncated cone shape, and the central axis (rotation axis) thereof is not parallel to the central axis.

The light source device 13a of this embodiment includes a light source (not shown) and an illumination optical system ILa. The illumination optical system ILa is provided with a plurality of (e.g., six) illumination optical systems ILa1 to ILa6 arranged in the Y-axis direction in correspondence with each of the plurality of projection optical systems PL1 to PL6. The light source can use various light sources in the same manner as the various light source devices 13a described above. The illumination light emitted from the light source has a uniform illumination 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 a lens. Each of the plurality of illumination optical systems ILa1 to ILa6 includes, for example, an integrating optical system, a rod lens, a fly-eye lens, etc., and the illumination region IR is illuminated by the illumination light beam EL1 with a uniform illumination 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 passes through the mask holding cylinder 21a from the inside of the mask holding cylinder 21a to illuminate and hold each illuminated area on the mask MA on the outer peripheral surface of the mask holding cylinder 21a.

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

When the exposure device U3a uses a transmissive mask as the photomask, the exposure device U3a is also the same as the exposure devices U3 and U3a. The relationship between the projection image surface and the exposure surface is set as described above. The positional relationship of the in-focus state can obtain the same effects as described above.

[Fourth Embodiment]

Next, an exposure apparatus U3c according to the fourth embodiment will be described with reference to Fig. 19. In order to avoid repetitive descriptions, only the parts that are different from the first embodiment will be described, and the same components as those of the first embodiment will be given the same symbols as those of the first embodiment. FIG. 19 is a diagram showing the overall configuration of an exposure apparatus (substrate processing apparatus) according to a fourth embodiment. Although the exposure apparatus U3 of the first embodiment uses a configuration in which a cylindrical reflection mask M is held by a rotatable mask holding cylinder 21, the exposure apparatus U3c of the fourth embodiment uses a flat plate. The reflective mask MB is configured to be 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 that holds a planar mask MB and the mask stage 110 along the X direction in a plane orthogonal to the center plane CL. Scan a mobile device (not shown).

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

Where the main ray of the illumination beam EL1 illuminated on the mask MB is perpendicular to the XY plane, the polarizing beam splitter PBS is configured to enter the main beam of the illumination beam EL1 of the quarter-wave plate 41 at an incident angle θ 1 It becomes the Brewster angle θ B, and the main ray of the illumination light beam EL1 reflected by the 1/4 wavelength plate 41 is perpendicular to the XY plane. With the change of the configuration of the polarizing beam splitter PBS, the configuration of the illumination optical module ILM is also changed appropriately.

When the main 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 It is assumed that the projection light beam EL2 from the polarizing beam splitter PBS is reflected, and the reflected projection light beam EL2 passes through the first lens group 71 and enters the first concave mirror 72 at an angle. 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).

Also, the fourth embodiment is the same as the previous FIG. 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 from the center point of the projection area PA1 (and PA3, PA5) on the substrate P running along the support surface P2 to the center point of the second projection area PA2 (and PA4, PA6). The perimeters are substantially equal.

Similarly to the exposure device U3c of FIG. 19, the lower control device 16 controls the moving device (the linear motor for scanning exposure or the actuator for micro-movement) of the mask holding mechanism 11 in synchronization with the rotation of the substrate support cylinder 25 Drive the photomask stage 110. The exposure device U3c of FIG. 19 must perform the operation (roll-back) of returning the mask MB to the initial position in the -X direction after scanning exposure during the synchronous movement of the mask MB 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 exposure on the substrate P is not performed during the rewinding operation of the photomask MB, but is attached to the substrate. The conveying direction of P forms a pattern for a panel intermittently (separately). However, in practice, since the speed of the substrate P (here, the peripheral speed) and the speed of the photomask MB during scanning exposure are assumed to be 50 to 100 mm / s, it is only necessary to load the photomask when the photomask MB is rolled back. The stage 110 is driven at a maximum speed of, for example, 500 mm / s, that is, the blank space of the pattern for the panel formed on the substrate P in the conveying direction can be reduced.

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

The exposure device U3c images the projection light beam EL2 by the projection optical system PL to form a projection image surface Sm2 of the pattern of the mask MB. The projection image surface Sm2 is a position where the pattern of the mask MB is imaged, and it is a position for optimal focusing. Here, the photomask MB is arranged in a plane as described above. Thereby, the projection image plane Sm2 also becomes a plane (a straight line in the ZX plane). In the exposure device U3c, the surface of the substrate P is an exposure surface Sp. Here, the exposure surface Sp is the surface of the substrate P. The substrate P is held in 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 curvature radius Rm. The exposure surface Sp is an axis having a curved surface in a direction orthogonal to the scanning exposure direction. Therefore, the exposure surface Sp shown in FIG. 20 is a curved curve with respect to the scanning exposure direction. The amount of change in the exposure surface Sp at the position of the exposure width A in the scanning exposure direction in the projection area PA is Δp. The projection image plane Sm2 is a plane. 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 relative 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 different from the projection image surface Sm2 in the scanning exposure direction. In addition, the exposure device U3c can adjust the distance between the mask MB and the substrate P by adjusting the position of each optical member of the projection optical system PL or the mask holding mechanism 11b and the substrate supporting mechanism 12 with respect to the projection. The position of the exposure surface of the image plane Sm2 changes.

In the exposure device U3c, the projection image plane Sm2 and the actual exposure plane Spa intersect at two different positions Pa2, Pb2, thereby, within the exposure width A, the focus state becomes the most in the position Pa2 on the actual exposure plane Spa. The best focus is achieved at 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, can be used to project the mask pattern onto the scanning exposure direction of the substrate P in the same manner as the exposure devices U3, U3a, and U3b. The projected image surface Sm2 and the exposed surface Sp of the exposed substrate P give a cylindrical shape difference. Furthermore, in the exposure device U3c, the projection image plane Sm2 and the actual exposure plane Spa intersect at two different positions Pa2, Pb2, and the focus state of the exposure plane becomes the best focus in the two different positions.

In this way, the exposure device U3c can similarly change the focus state continuously within the exposure width A of the scanning exposure direction by holding the rotary motion of the cylinder 21, thereby suppressing the contrast of the image with respect to the actual focus. Variety. The exposure device U3c can also obtain various effects similar to those of the exposure device U3. As described above, even when only one of the projection surface and the exposure surface (the surface of the substrate P) is formed into a curved surface, the same effects as those obtained when the projection surface and the exposure surface are formed into a curved surface can be obtained.

Here, the exposure device U3c can calculate the dispersion in a circular arc shape 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 in the above formula to 0. Focal width Δ.

Δ = r ₂ -((r ₂ ² )-(A / 2) ² ) ^1/2

Here, in the exposure device U3c, since the curvature radius of the projection image surface Sm2 of the mask pattern is ∞, the defocus characteristic Cm that changes in an arc shape within the exposure width A is obtained only by the previous Equation 3. That is, the defocus characteristic Cm (= ΔRp) in the case of the exposure device U3c is based on Come to find out.

In the exposure apparatus of this embodiment, among the mask holding mechanism and the substrate supporting mechanism, a curved surface holder is used as the first supporting member, and a curved surface or planar support is used as the second supporting member.

<Exposure method>

Next, an exposure method will be described with reference to FIG. 21. FIG. 21 is a flowchart showing an exposure method.

In the exposure method shown in FIG. 21, first, the substrate P is supported on the supporting surface P2 by a substrate supporting mechanism (step S101), and the photomask M is supported on the surface P1 by a mask holding mechanism (step S102). As a result, the photomask M and the substrate P face each other. In addition, the order of steps S101 and S102 may be reversed. One of the surfaces P1 and the support surface P2 is a first surface, and the other is a second surface. The first surface is a shape curved into a cylindrical surface with a predetermined curvature.

Next, the focus position with respect to the exposure surface is adjusted (step S103). Specifically, the focus position is set within the exposure width A of the projection area PA set on the surface of the substrate P, at a position including two optimal 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, an operation of moving at least one of the substrate P and the mask M in the scanning exposure direction is started by at least one of the substrate supporting mechanism and the mask holding mechanism.

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

The exposure method is to project the beam after adjusting the focus position in the above manner, so that the beam including the two optimal focus positions in the scanning exposure direction can be projected on the projection area on the exposure surface of the substrate P. Thereby, various effects described above can be obtained. In addition, although the case of adjusting the focus position has been described in this embodiment, a position including two optimal focus positions in the scanning exposure direction may be the focus position depending on the setting of the device.

<Element Manufacturing Method>

Next, a device manufacturing method will be described with reference to FIG. 22. FIG. 22 is a flowchart showing a component manufacturing method of the component manufacturing system.

The element manufacturing method shown in FIG. 22 is to first perform a function and performance design of a display panel formed using a self-luminous element such as an organic EL, and design a circuit pattern and a wiring pattern required by CAD or the like (step S201). Next, a mask M of a desired layer amount is produced based on various patterns of each layer designed by CAD or the like (step S202). A supply roll FR1 on which a flexible substrate P (resin film, metal foil film, plastic, etc.) as a base material of the display panel is wound is prepared (step S203). In addition, the roll-shaped substrate P prepared in this step S203 may be one whose surface has been modified as necessary, or which has been previously formed with a bottom layer (for example, through minute irregularities of an imprint method), or laminated with light in advance. Inductive functional film or transparent film (insulating material).

Next, an electrode constituting a display panel element or a substrate layer composed of wiring, an insulating film, a TFT (thin film semiconductor), and the like is formed on the substrate P, and a light emission composed of a self-emitting element such as an organic EL is laminated on the substrate. Layer (display pixel portion) (step S204). In this step S204, although the conventional lithography process is used to expose the photoresist layer using the exposure device U3 described in the previous embodiments, it also includes a substrate P pattern 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 a photo-sensitive catalyst layer pattern and forms a metal film pattern (wiring, electrodes, etc.) by an electroless plating method, or a silver-containing process Processing such as printing process for drawing patterns such as conductive ink of rice particles.

Next, for each display panel element that is continuously manufactured on the long substrate P by a roll method, the substrate P is cut, or a protective film (environmental barrier layer) or a color filter film is laminated on the surface of each display panel element. The components are assembled (step S205). Next, a step of checking whether the display panel element can operate normally or whether it satisfies the desired performance and characteristics is performed (step S206). Through the above method, a display panel (flexible display) can be manufactured.

Claims (15)

    A scanning exposure device for holding a mask holding cylinder that holds a mask pattern along a circumferential surface curved from a first axis to a first radius, rotates the first axis as a center, and moves a flexible substrate along the first axis. The scanning exposure direction of the surface, in order to expose the mask pattern on the surface of the substrate, includes: an illumination optical system, which illuminates illumination light toward an illumination region, the illumination region being set on the mask pattern on the first axis The direction is a slender rectangle or rectangle, and is set to have a predetermined width in the circumferential direction of the circumferential surface corresponding to the scanning exposure direction; the projection optics uses the light from the mask pattern to appear in the lighting area. The light beam is projected onto a projection area on the substrate side corresponding to the illumination area, so that the image of the mask pattern is imaged along a projection image surface curved in the scanning exposure direction corresponding to the first radius; and a substrate support cylinder The substrate is supported by bending the substrate from a second axis arranged parallel to the first axis and bending the outer peripheral surface into a cylindrical surface with a second radius. The second axis is rotated as a center to move the substrate in a circumferential direction of the outer peripheral surface corresponding to the scanning exposure direction; the mask holding cylinder, the substrate supporting cylinder, and the projection optical system are set to be curved. The projection image plane and the curved surface of the substrate intersect at two points separated by the scanning exposure direction in the projection region.         For example, the scanning exposure device of the first patent application range, wherein each of the projection optical system, the mask holding cylinder, and the substrate support cylinder is set so that the projection optical system is projected on the substrate by the projection optical system. When the defocus amount of the projection region of the light beam at 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 scope of the patent application, wherein the relationship between the aforementioned defocus amount Δ and the aforementioned focal depth DOF satisfies 1 ≦ Δ / DOF.         For example, the scanning exposure device of the second scope of the patent application, wherein the defocus amount of the projection surface of the mask pattern and the surface of the substrate is projected by the projection optical system with the best focus and projected in the projection area, 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 according to any one of claims 1 to 4, wherein the projection optical system has a plurality of division projection optical systems; the division projection optical systems are respectively on the first axis and the second axis. The extending direction is arranged in a column shape in a direction orthogonal to the scanning exposure direction, and the light beams are respectively projected onto the corresponding projection areas.         For example, the scanning exposure device of the fifth scope of the patent application, wherein the plurality of division projection optical systems are arranged in at least two rows in the scanning exposure direction and are arranged adjacent to each other in a direction orthogonal to the scanning exposure direction Ends of the projection areas corresponding to each of the divided projection optical systems overlap each other.         For example, the scanning exposure device of the sixth scope of the application for a patent, wherein the scanning exposure device is configured to integrate the exposure width of the projection area corresponding to each of the plurality of divided projection optical systems in the scanning exposure direction. The direction orthogonal to the scanning exposure direction is constant.         For example, the scanning exposure device of the 6th or 7th in the scope of patent application, wherein each of the plurality of division projection optical systems is a plurality of deflection members, lens groups, And a concave mirror arranged on the pupil surface is configured as a telecentric refracting optical system that deforms the Dyson system.     For example, the scanning exposure device according to any one of claims 1 to 4, wherein the exposure width of the projection area in the scanning exposure direction is set to A, and the radius of the curved projection image plane is set to r. _1. Set the radius of the curved substrate surface to r ₂ , set the numerical aperture of the projection optical system to NA, and set the wavelength of the illumination light to λ 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 of relationship. For example, the scanning exposure device of the ninth scope of the 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 ) < The relationship between r ₁ -((r ₁ ² )-(A / 2) ² ) ^1/2 + r ₂ -((r ₂ ² )-(A / 2) ² ) ^1/2 .     A scanning exposure method that moves a flexible substrate and a mask pattern in a scanning exposure direction with respect to a projection optical system to expose the aforementioned mask pattern on the surface of the substrate includes: The operation of rotating the photomask holding cylinder around the first axis while holding the first axis of the photomask holding cylinder around the first circumferential surface bent at a predetermined radius; The second axis set in parallel with the first axis is supported by bending the substrate with a second circumferential surface bent at a predetermined radius, and rotating the substrate supporting cylinder around the second axis; toward the lighting The area is irradiated with illumination light. The illumination area is set on the mask pattern to be an elongated rectangle or rectangle in the direction of the first axis, and is set to correspond to the scanning exposure direction on the first circumferential surface. Having a predetermined width in the circumferential direction; and projecting an optical system toward the substrate corresponding to the illumination area by projecting an optical beam from the mask pattern appearing in the illumination area The projection area on the side is projected, so that the image of the mask pattern is formed along the projection image surface curved in the scanning exposure direction corresponding to the radius of the first circumferential surface, and the projection image surface and the surface of the substrate are in the focusing direction. The positional relationship is set as a motion in which the curved projection image surface and the curved surface of the substrate intersect with each other at two points separated by the scanning exposure direction in the projection area.         For example, the scanning exposure method according to claim 11 of the application, 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 according to the 11th or 12th of the scope of patent application, wherein each of the aforementioned projection optical system, the aforementioned mask holding cylinder, and the aforementioned substrate supporting cylinder is set so that When the defocus amount of the projection region of the light beam of the substrate at 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 method according to item 13 of the scope of the patent application, wherein the relationship between the aforementioned defocus amount Δ and the aforementioned focal depth DOF satisfies 1 ≦ Δ / DOF.         For example, the scanning exposure method of the 13th aspect of the patent application, wherein the curved projection image surface of the mask pattern and the surface of the curved substrate are projected with the best projection by the aforementioned projection optical system in the projection area. 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.