JP2013218156A - Exposure apparatus and substrate processing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exposure apparatus and a substrate processing apparatus which are excellent in optical performance.SOLUTION: An exposure apparatus exposes a substrate by projecting an image of a pattern formed in a mask onto a sheet-like substrate with exposure light. The exposure apparatus includes a substrate support device provided with a curvature forming part supporting the substrate in a state where a portion of the substrate onto which the image is projected is curved, and an adjustment member which adjusts a light path length of exposure light in accordance with the curved portion of the substrate.

Description

  The present invention relates to an exposure apparatus and a substrate processing apparatus.

  As display elements that constitute display devices such as display devices, for example, liquid crystal display elements and organic electroluminescence (organic EL) elements are known. Currently, in these display elements, active elements (active devices) that form thin film transistors (TFTs) on the substrate surface corresponding to each pixel have become mainstream.

  In recent years, a technique for forming a display element on a flexible substrate (for example, a film member) has been proposed. As such a technique, for example, a technique called a roll-to-roll system (hereinafter simply referred to as “roll system”) is known (see, for example, Patent Document 1). In the roll method, the belt-shaped substrate wound around the substrate supply side supply roller is sent out, and the substrate is transported while being wound up by the substrate recovery side recovery roller.

  A gate electrode, a gate oxide film, a semiconductor film, a source / drain electrode, and the like constituting the TFT are formed by a plurality of processing apparatuses from when the substrate is sent out until it is wound. Thereafter, other components of the display element are sequentially formed on the substrate. For example, when an organic EL element is formed on a substrate, a light emitting layer, an anode, a cathode, an electric circuit, and the like are sequentially formed on the substrate. These components may be formed using, for example, a photolithography method using an exposure apparatus that exposes the substrate with exposure light through a mask, for example.

International Publication No. 2006/100868

  By the way, even in the roll method as described above, there is a demand for a technology that enables a display element to be manufactured with high accuracy on a belt-like substrate. For this reason, an exposure apparatus having excellent optical performance is required.

  In view of the above, an object of an aspect of the present invention is to provide an exposure apparatus and a substrate processing apparatus excellent in optical performance.

  According to a first aspect of the present invention, there is provided an exposure apparatus that exposes a substrate by projecting an image of a pattern formed by exposure light on a mask onto a sheet-like substrate, wherein a portion of the substrate on which an image is projected is provided. An exposure apparatus is provided that includes a substrate support device provided with a curve forming portion that supports the substrate so as to be bent, and an adjustment member that adjusts the optical path length of exposure light in correspondence with the curved portion of the substrate.

  According to a second aspect of the present invention, a substrate transport unit that transports a substrate and a substrate processing unit that processes the substrate, the substrate processing unit having the exposure apparatus according to the first aspect of the present invention. A processing device is provided.

  According to the aspect of the present invention, it is possible to provide an exposure apparatus and a substrate processing apparatus having excellent optical performance.

1 is a diagram showing a configuration of an exposure apparatus according to a first embodiment of the present invention. The figure for demonstrating the principle of the adjustment mechanism which concerns on this embodiment. The figure which shows the structure of the device manufacturing system which concerns on 2nd embodiment of this invention. The figure which shows the structure of the exposure apparatus which concerns on the modification of this embodiment. The figure which shows the structure of the exposure apparatus which concerns on the modification of this embodiment. The figure which shows the structure of the exposure apparatus which concerns on the modification of this embodiment. The figure which shows the structure of the exposure apparatus which concerns on the modification of this embodiment. The figure which shows the structure of the exposure apparatus which concerns on the modification of this embodiment.

[First embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a view showing the arrangement of the exposure apparatus EX according to this embodiment.
As shown in FIG. 1, the exposure apparatus EX includes an illumination unit IU, a mask stage MST, a projection optical system PL, a substrate stage SST, and a control device. The exposure apparatus EX projects an image Im by the exposure light ELI of the pattern P formed on the mask M onto the sheet-like substrate S.

  In FIG. 1, an orthogonal coordinate system XYZ is set such that the pattern formation surface Ma of the mask M is perpendicular to the XZ plane, and the width direction orthogonal to the transport direction (long direction) of the substrate S is set to the Y direction. Shall be. The substrate S may be activated by modifying the surface in advance by a predetermined pretreatment, or may be formed with a fine partition structure (uneven structure) for precise patterning on the surface.

  As the substrate S, for example, a foil such as a resin film or stainless steel can be used. For example, the resin film is made of polyethylene resin, polypropylene resin, polyester resin, ethylene vinyl copolymer resin, polyvinyl chloride resin, cellulose resin, polyamide resin, polyimide resin, polycarbonate resin, polystyrene resin, vinyl acetate resin, etc. Can be used.

  The substrate S preferably has a smaller coefficient of thermal expansion so that the dimensions do not change even when subjected to heat of about 200 ° C., for example. For example, an inorganic filler can be mixed with a resin film to reduce the thermal expansion coefficient. Examples of the inorganic filler include titanium oxide, zinc oxide, alumina, silicon oxide and the like. The substrate S may be a single piece of ultrathin glass having a thickness of about 100 μm manufactured by a float process or the like, or a laminate in which the resin film or aluminum foil is bonded to the ultrathin glass.

  The dimension in the width direction (short direction) of the substrate S is, for example, about 1 m to 2 m, and the dimension in the length direction (long direction) is, for example, 10 m or more. Of course, this dimension is only an example and is not limited thereto. For example, the dimension in the Y direction of the substrate S may be 50 cm or less, or 2 m or more. Moreover, the dimension of the X direction of the board | substrate S may be 10 m or less.

  The substrate S is formed so as to have flexibility. Here, the term “flexibility” refers to the property that the substrate can be bent without being broken or broken even if a force of its own weight is applied to the substrate. In addition, flexibility includes a property of bending by a force of about its own weight. The flexibility varies depending on the material, size, thickness, environment such as temperature, etc. of the substrate. As the substrate S, a single strip-shaped substrate may be used, but a configuration in which a plurality of unit substrates are connected and formed in a strip shape may be used.

  The illumination unit IU illuminates the exposure light ELI on the mask M. In the present embodiment, a mask M on a flat plate is used as the mask M. A predetermined pattern P is formed on the pattern forming surface (object surface) Ma of the mask M. As the mask M, a transmissive mask that transmits the exposure light ELI from the illumination unit IU is used. However, the mask M is not limited to this, and a reflective mask that reflects the exposure light ELI from the illumination unit IU may be used. good.

  Mask stage MST is movable while holding mask M. The mask stage MST has a drive mechanism (not shown) that moves the mask M along the pattern formation surface Ma. The exposure light ELI is scanned over the entire pattern P by the mask stage MST moving the mask M.

  The projection optical system PL includes lenses 31 to 34 that project an image of the pattern P formed on the mask M onto the substrate S. As the projection optical system PL, for example, an enlargement optical system that enlarges and projects an image of the pattern P formed on the mask M (that is, an optical system having an enlargement magnification as a projection magnification) is used. Further, the projection optical system PL has an intermediate imaging 36, and the magnification of the intermediate imaging is a reduction magnification with respect to the image of the substrate S.

  The substrate stage SST transports the substrate S so as to pass through each projection area PA on which an image of the pattern P is projected by the projection optical system PL. The substrate stage SST has a substrate support roller 80. In addition, the substrate stage SST has a drive unit 81 that moves the substrate support roller 80 in the X direction, the Y direction, and the Z direction, and rotates it in the θY direction.

  In the substrate stage SST, the substrate support roller 80 is formed in a cylindrical shape, and is disposed at a position corresponding to the projection area PA of the image of the pattern P by the projection optical system PL. The outer peripheral surface of the substrate support roller 80 is a support surface 80 a that supports the substrate S. The substrate support roller 80 is provided with an air bearing mechanism (not shown), and the air bearing mechanism may support the substrate S on the support surface 80a in a non-contact manner.

  In the present embodiment, in the projection optical system PL of the exposure apparatus EX configured as described above, the projection position of the projection image (pattern P image) is adjusted in a direction along the surface Sa of the substrate S supported by the support surface 80a. A possible adjustment mechanism 35 is provided. The adjustment mechanism 35 adjusts the optical path length in the X direction of the exposure light ELI.

  The surface Sa of the substrate S supported by the support surface 80a formed in a cylindrical shape as in the present embodiment is disposed on the cylindrical surface. On the other hand, the mask M is formed in a planar shape, and the pattern P is disposed in a planar shape. Therefore, when the image Im of the pattern P of the mask M is projected onto the surface Sa of the substrate S, it is necessary to adjust the image Im in the direction along the surface Sa of the substrate S supported by the support surface 80a.

FIG. 2 is a diagram for explaining the principle of adjusting the image Im.
As shown in FIG. 2, when a cylindrical surface 51 having a radius of curvature R is set and a plane 52 in contact with the cylindrical surface 51 is set, the cylindrical surface 51 from a position 54 on the plane 52 that is separated from the contact 53 by a distance H. The distance L to
L = R−√ (R ² −H ² )
It is.

  Therefore, if the projection optical system PL is configured such that an optical path difference (optical path difference L) equal to the distance L is generated in a light beam passing from the contact point 53 to the position 54 in the plane 52, the substrate S arranged as a cylindrical surface. The image Im of the pattern P can be projected on the surface Sa with good optical performance. Therefore, in the present embodiment, the adjustment mechanism 35 is disposed in the projection optical system PL.

  In this embodiment, for example, a photorefractive member 37 that can transmit the exposure light ELI and has a light refractive index distribution in the curvature direction (X direction) is used as the adjusting mechanism 35. The photorefractive member 37 is provided on the downstream side of the mask M in the traveling direction of the exposure light ELI. The photorefractive member 37 is disposed in the vicinity of the object plane (pattern formation surface Ma) and the conjugate position in the projection optical system PL. In this case, if the light refractive index distribution in the X direction of the light refracting member 37 has a light refractive index distribution having the above optical path difference, the image plane of the pattern P forms a cylindrical surface. The light refracting member 37 may be arranged at a position 39 that is a conjugate position with the light refracting member 37 in the projection optical system PL.

  As described above, according to the present embodiment, the exposure apparatus EX that exposes the substrate S by projecting the image Im by the exposure light ELI of the pattern P formed on the mask M onto the sheet-like substrate S. The substrate support roller 80 provided with a support surface 80a for supporting the substrate S so as to curve the projection area PA on which the image Im is projected, and the optical path length of the exposure light ELI corresponding to the curved portion of the substrate S. Since the adjusting mechanism 35 for adjusting is provided, the adjusting mechanism 35 can adjust the image Im of the pattern P so as to correspond to the shape of the substrate S. Thereby, the exposure apparatus EX excellent in optical performance is realizable.

[Second Embodiment]
Next, a second embodiment of the present invention will be described.
In the present embodiment, a device manufacturing system including the exposure apparatus EX described in the first embodiment will be described. FIG. 3 is a diagram showing a partial configuration of the device manufacturing system (flexible display manufacturing line) of the present embodiment. Here, the flexible substrate S (sheet, film, etc.) drawn out from the supply roll FR1 passes through n processing devices U1, U2, U3, U4, U5,. The example until it winds up to FR2 is shown.

  In FIG. 3, the orthogonal coordinate system XYZ is set so that the front surface (or back surface) of the substrate S is perpendicular to the XZ plane, and the width direction orthogonal to the transport direction (long direction) of the substrate S is set to the Y direction. Shall be. The substrate S may be activated by modifying the surface in advance by a predetermined pretreatment, or may be formed with a fine partition structure (uneven structure) for precise patterning on the surface.

  The substrate S wound around the supply roll FR1 is pulled out by the nipped drive roller DR1 and transported to the processing apparatus U1. The center of the substrate S in the Y direction (width direction) is controlled by the edge position controller EPC1. Servo control is performed so as to be within a range of about ± 10 μm to several tens μm with respect to the position.

  The processing device U1 continuously or selects a photosensitive functional liquid (photoresist, photosensitive coupling material, UV curable resin liquid, etc.) on the surface of the substrate S by a printing method with respect to the transport direction (long direction) of the substrate S. It is the coating device which coats automatically. In the processing apparatus U1, a coating mechanism including a pressure drum DR2 around which the substrate S is wound, a coating roller for uniformly coating the photosensitive functional liquid on the surface of the substrate S on the pressure drum DR2. Gp1, a drying mechanism Gp2 for rapidly removing the solvent or moisture contained in the photosensitive functional liquid applied to the substrate S, and the like are provided.

  The processing device U2 heats the substrate S conveyed from the processing device U1 to a predetermined temperature (for example, about several tens of degrees Celsius to 120 ° C.) to stably fix the photosensitive functional layer applied on the surface. It is a heating device. In the processing apparatus U2, a plurality of rollers and an air turn bar for returning and conveying the substrate S, a heating chamber HA1 for heating the loaded substrate S, and the temperature of the heated substrate S, A cooling chamber HA2 and a nipped drive roller DR3 are provided for lowering the temperature so as to match the environmental temperature of the post-process (processing device U3).

  The processing device U3 is an exposure device EX that irradiates the photosensitive functional layer of the substrate S conveyed from the processing device U2 with ultraviolet patterning light corresponding to the circuit pattern and wiring pattern for display. In the processing apparatus U3, an edge position controller EPC that controls the center of the substrate S in the Y direction (width direction) to a fixed position, a nipped drive roller DR4, and the back surface of the substrate S that is conveyed in the X direction with a predetermined tension Are provided with a substrate transport device ST which is plane-supported by an air bearing layer, and two sets of drive rollers DR6 and DR7 for giving a predetermined slack (play) DL to the substrate S.

  The processing apparatus U4 in FIG. 3 is a wet processing apparatus that performs wet development processing, electroless plating processing, and the like on the photosensitive functional layer of the substrate S conveyed from the processing apparatus U3. In the processing apparatus U4, three processing tanks BT1, BT2, and BT3 layered in the Z direction, a plurality of rollers that fold and convey the substrate S, a nip driving roller DR8, and the like are provided.

  The processing device U5 is a heating and drying device that warms the substrate S transported from the processing device U4 and adjusts the moisture content of the substrate S wet by the wet process to a predetermined value, but the details are omitted. After that, the substrate S that has passed through several processing apparatuses and passed through the last processing apparatus Un of the series of processes is wound up on the collection roll FR2 via the nipped drive roller DR1. Also during the winding, the edge position controller EPC2 controls the Y of the drive roller DR1 and the recovery roll FR2 so that the center in the Y direction (width direction) of the substrate S or the substrate end in the Y direction does not vary in the Y direction. The relative position in the direction is successively corrected and controlled.

  The host controller 5 controls the operation of the processing devices U1 to Un constituting the production line, monitors the processing status and processing status of the processing devices U1 to Un, and the substrate S between the processing devices. It also monitors the conveyance status, and performs feedback correction and feedforward correction based on the results of prior and subsequent inspections and measurements.

  The board | substrate S used by this embodiment is foil (foil) etc. which consist of metals or alloys, such as a resin film and stainless steel, for example. The material of the resin film is, for example, one of polyethylene resin, polypropylene resin, polyester resin, ethylene vinyl copolymer resin, polyvinyl chloride resin, cellulose resin, polyamide resin, polyimide resin, polycarbonate resin, polystyrene resin, and vinyl acetate resin. Or two or more.

  As the substrate S, it is desirable to select a substrate whose coefficient of thermal expansion is not remarkably large so that the amount of deformation caused by heat in various processing steps can be substantially ignored. The thermal expansion coefficient may be set smaller than a threshold corresponding to the process temperature or the like, for example, by mixing an inorganic filler with a resin film. The inorganic filler may be, for example, titanium oxide, zinc oxide, alumina, silicon oxide or the like. The substrate S may be a single layer of ultrathin glass having a thickness of about 100 μm manufactured by a float process or the like, or a laminate in which the above resin film, foil, or the like is bonded to the ultrathin glass. It may be.

  The device manufacturing system 1 according to the present embodiment repeatedly or continuously executes various processes for manufacturing a device (display panel or the like) on the substrate S. The substrate S that has been subjected to various types of processing is divided (diced) for each device to form a plurality of devices. As for the dimension of the substrate S, for example, the dimension in the width direction (short Y direction) is about 10 cm to 2 m, and the length direction (long X direction) is 10 m or more.

  As described above, according to the present embodiment, since the exposure apparatus EX excellent in optical performance is mounted, the display element can be manufactured on the belt-like substrate S with high accuracy.

The technical scope of the present invention is not limited to the above-described embodiment, and appropriate modifications can be made without departing from the spirit of the present invention.
For example, in the above-described embodiment, the adjustment mechanism 35 has been described by taking as an example a configuration in which the adjustment mechanism 35 is disposed in the vicinity of the conjugate plane with the object plane (pattern formation surface Ma) of the projection optical system PL. There is no.

  For example, as shown in FIG. 4, the adjustment mechanism 35 may be arranged in the vicinity of the intermediate imaging 36. In this case, as the adjustment mechanism 35, a light refraction member 37 in which a light refractive index distribution is formed in the X direction is disposed as in the above embodiment. The photorefractive member 37 is configured to generate a predetermined optical path difference at the position of the intermediate imaging 36 so that an optical path difference L is formed on the surface Sa of the substrate S so that the image plane of the pattern P becomes a cylindrical surface. It is.

  For example, as shown in FIG. 5, a configuration in which a concave cylindrical lens 38 is disposed in the vicinity of the intermediate imaging 36 as the adjustment mechanism 35 may be employed. In this case, the concave cylindrical lens 38 generates a predetermined optical path difference at the position of the intermediate imaging 36 so that an optical path difference L is formed on the surface Sa of the substrate S so that the image plane of the pattern P becomes a cylindrical surface. It is the structure to make.

  Further, for example, as shown in FIG. 6, a configuration in which a concave mirror 43 is disposed in the vicinity of the intermediate imaging 36 as the adjustment mechanism 35 may be employed. In the configuration shown in FIG. 6, the projection optical system PL includes a dichroic prism 41, a lens 32, a concave mirror 42, a concave mirror 43, a lens 33, and a lens 34, and the exposure light ELI includes the first intermediate image 36a and the second optical image 36a. The intermediate image 36b is configured to connect the two intermediate images 36b. In the projection optical system PL, the concave mirror 43 is disposed in the vicinity of the first intermediate image 36a.

  The exposure light ELI from the illumination unit IU enters the lens 32 via the dichroic prism 41 and passes through the lens 32. The exposure light ELI is reflected by the concave mirror 42, passes through the lens 32 again, and reaches the concave mirror 43 disposed in the vicinity of the intermediate image 36.

  The exposure light ELI that has reached the concave mirror 43 forms a first intermediate image 36 a in the vicinity of the concave mirror 43. Thereafter, the exposure light ELI is reflected by the concave mirror 43, passes through the lens 32, is reflected by the concave mirror 42, passes through the lens 32 again, and passes through the dichroic prism 41. The exposure light ELI transmitted through the dichroic prism 41 forms a second intermediate image 36b. Thereafter, the exposure light ELI is projected onto the projection area PA of the surface Sa of the substrate S through the lens 33 and the lens 34.

  In this configuration, the concave mirror 43 has a predetermined optical path difference at the position of the first intermediate image 36a so that an optical path difference L is formed on the surface Sa of the substrate S so that the image plane of the pattern P becomes a cylindrical surface. It is the structure which generates. In the configuration shown in FIG. 6, the adjustment mechanism 35 (concave mirror 43) is provided only in the vicinity of the first intermediate imaging 36a. However, the configuration is not limited to this. For example, the adjustment mechanism 35 may be separately provided in the vicinity of the second intermediate imaging 36b. In this case, each adjustment mechanism 35 may be designed so that the total value of the adjustment amounts in all the adjustment mechanisms 35 becomes the optical path difference L.

  Further, for example, as shown in FIG. 7, a configuration in which a plurality of adjustment mechanisms 35 are arranged for one intermediate imaging 36 may be employed. In the configuration shown in FIG. 7, a first light refraction member 37 a and a second light refraction member 37 b are provided as the adjustment mechanism 35. The first light refracting member 37a and the second light refracting member 37b are arranged at a position sandwiching the intermediate imaging 36 in the traveling direction of the exposure light ELI. In FIG. 7, a mask stage MST having a rotator 55 that detachably holds the reflective mask M is provided. Accordingly, the exposure apparatus EX is configured to project the pattern P of the reflective mask M held in a convex shape by the mask stage MST onto the surface Sa of the substrate S supported by the convex support surface 80a. Yes. In this case, the optical path difference L needs to be larger than the optical path difference L when the flat pattern P is projected onto the surface Sa of the convex substrate S. In such a case, by arranging the plurality of adjusting mechanisms 35, the image plane of the pattern P can be formed on the cylindrical surface while reducing aberration. In the configuration shown in FIG. 7, for example, an optical path difference is generated by the first light refracting member 37a so that the image plane of the intermediate image 36 becomes a plane, and the surface Sa of the substrate S is formed by the second light refracting member 37b. The optical path difference can be generated so as to form a cylindrical surface corresponding to.

  Moreover, in the said embodiment, although the structure when the board | substrate S was supported by convex shape was mentioned as an example and demonstrated, it is not restricted to this. For example, as shown in FIG. 8, even when the substrate S is supported in a concave shape, the adjustment mechanism 35 can be arranged. In this case, the adjustment mechanism 35 may be configured to generate an optical path difference L such that the image plane of the pattern P is a concave surface.

  EX ... Exposure apparatus PL ... Projection optical system SST ... Substrate stage M ... Mask P ... Pattern ELI ... Exposure light Im ... Image S ... Substrate Ma ... Pattern formation surface PA ... Projection area Sa ... Surface 1 ... Device manufacturing system 35 ... Adjustment mechanism 36 ... Intermediate imaging 36a ... First intermediate imaging 36b ... Second intermediate imaging 37 ... Light refraction member 37a ... First light refraction member 37b ... Second light refraction member 38 ... Concave cylindrical lens 39 ... Position 41 ... Dichroic prism 43 ... concave mirror 55 ... rotating body 80 ... substrate support roller

Claims (12)

An exposure apparatus that exposes the substrate by projecting an image of exposure light of a pattern formed on the mask onto a sheet-like substrate,
A substrate support device provided with a curve forming portion for supporting the substrate so as to curve a portion of the substrate on which the image is projected;
An exposure apparatus comprising: an adjustment member that adjusts an optical path length of the exposure light corresponding to a curved portion of the substrate. The exposure apparatus according to claim 1, wherein the adjustment member is provided on the downstream side of the mask in the traveling direction of the exposure light. A projection optical system for projecting the image onto the substrate;
3. The adjustment member according to claim 1, wherein the adjustment member is disposed at at least one of a first position close to the mask and a second position conjugate with the first position in the projection optical system. Exposure device. A projection optical system for projecting the image onto the substrate;
The projection optical system is formed to image the exposure light at an intermediate imaging position between the mask and the substrate,
The exposure apparatus according to any one of claims 1 to 3, wherein the adjustment member is disposed at a position sandwiching the intermediate imaging position in an optical path of the exposure light. The exposure apparatus according to any one of claims 1 to 4, wherein the adjustment member has a cylindrical surface. 6. The adjustment member according to claim 1, wherein the adjustment member is formed in a flat plate shape, and a refractive index distribution of the exposure light is formed so as to correspond to the curved portion. Exposure device. The mask is formed in a sheet shape,
The exposure apparatus according to any one of claims 1 to 6, further comprising a mask holding device having a rotating body that detachably holds the mask. The exposure apparatus according to any one of claims 1 to 6, wherein the mask is formed in a flat plate shape. The exposure apparatus according to any one of claims 1 to 8, wherein the curve forming portion includes a convex portion that supports the substrate. The exposure apparatus according to any one of claims 1 to 8, wherein the curve forming portion includes a recess that supports the substrate. The substrate support device has a guide roller for guiding the substrate,
The exposure apparatus according to any one of claims 1 to 8, wherein the curve forming portion is a part of a surface of the guide roller. A substrate transport section for transporting the substrate;
A substrate processing section for processing the substrate,
The said substrate processing part has an exposure apparatus as described in any one of Claims 1-11. A substrate processing apparatus.

Images