JP5935294B2 - Proximity exposure apparatus and proximity exposure method - Google Patents

Description

  The present invention relates to a proximity exposure apparatus and a proximity exposure method, and more particularly to a proximity exposure apparatus and a proximity exposure method for exposing and transferring a mask pattern of a mask onto a substrate of a large flat panel display such as a liquid crystal display or a plasma display. .

  Conventionally, various exposure apparatuses such as a proximity exposure apparatus, a scan exposure apparatus, a projection exposure apparatus, a mirror projection, and a contact type exposure apparatus have been devised as apparatuses for manufacturing a panel such as a color filter of a flat panel display apparatus. For example, in the division sequential proximity exposure apparatus, a mask smaller than the substrate is held on the mask stage and the substrate is held on the work stage. By irradiating the substrate with pattern exposure light from the mask side at each step, a plurality of patterns drawn on the mask are exposed and transferred onto the substrate, and a plurality of panels are manufactured on one substrate. In the proximity scan exposure apparatus, exposure light is irradiated onto a substrate being conveyed at a constant speed through a mask, and a mask pattern is exposed and transferred onto the substrate.

  Further, in the proximity exposure apparatus, it is known to use a plurality of light sources instead of using a large lamp as an illumination optical system in order to increase the output of the light source (see, for example, Patent Documents 1 to 4). ).

  In the exposure apparatus described in Patent Document 1, it is described that an illuminance sensor is disposed on the back side of a plane mirror, and the illuminance is kept constant while changing the lighting and extinction of the light source over time. Moreover, in the light source device described in Patent Document 2, by measuring a plurality of light sources with one illuminance sensor and comparing the actual illuminance with a preset appropriate illuminance, Each light source is controlled so that the illuminance is constant.

  In addition, in the surface light source control device described in Patent Document 3, a grouping is performed in advance for each group in which the tendency of the illuminance distribution characteristics of each point light source at a position corresponding to the exposure surface is similar, and this corresponds to the exposure surface of the exposure object. Emission level determination means for determining the emission level of each point light source for which the illuminance distribution at the position is uniform is determined for each group to which the point light source belongs, and this emission level determination means is for point light sources belonging to the same group Controls each light source so as to have the same light emission level.

  In the exposure apparatus described in Patent Document 4, an illuminance sensor is provided for each light source, and each power source is feedback-controlled so that the detection result of each illuminance sensor becomes the determined target value of the illuminance of the lamp. Each light source is controlled so that becomes constant.

JP 2010-256428 A JP 2008-241877 A JP 2006-344747 A JP 2008-286971 A

By the way, in the proximity exposure apparatus, the gap of about 100 μm between the mask opening and the substrate to be exposed does not become constant at each position on the exposure surface because of the self-weight deflection of the mask and the thickness variation of the substrate. For this reason, non-uniformity occurs in the way the light strikes the photosensitive material, and variations due to the gap occur in the size of the pattern after exposure.
In addition, for the production of a color filter or a TFT substrate of a liquid crystal display panel, the exposure is repeated a plurality of times to perform superposition. Therefore, as the required resolution becomes higher, the size of the overlapped portion becomes smaller, and when the size variation is large, it is not possible to superimpose well. In the exposure apparatuses described in Patent Documents 1 to 4, there is no description about controlling the illuminance in consideration of the gap distribution.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to make it possible to reduce variations in illuminance on the exposure surface due to gap distribution by controlling the illuminance of a plurality of light source units, respectively. An exposure apparatus and a proximity exposure method are provided.

The above object of the present invention can be achieved by the following constitution.
(1) An illumination optical system including a plurality of light source units, a shutter, an integrator lens, and a collimation mirror is provided, and light is emitted from the illumination optical system toward a mask that is in close proximity to the substrate. A proximity exposure apparatus for exposing a mask pattern onto a substrate,
A gap measuring means for measuring a gap between the mask and the substrate at a plurality of locations in an exposure region;
The proximity exposure apparatus, wherein the plurality of light source units change illuminance according to gaps measured at a plurality of locations.
(2) The plurality of light source units may partially decrease the illuminance at a location where the measured gap is narrower than a set gap, and partially increase the illuminance at a location where the measured gap is wider than the set gap. The proximity exposure apparatus according to (1), characterized in that:
(3) the gap measuring means, proximity exposure apparatus according to (2) comprises a plurality of gap measuring means disposed respectively in the plurality of grooves provided on the word Kusuteji.
(4) the gap measuring means, proximity exposure apparatus according to (2) to be movably disposed in the groove provided in the word Kusuteji.
(5) The proximity exposure apparatus according to any one of (1) to (4), wherein the gap measuring unit is a gap sensor.
(6) An illumination optical system having a plurality of light source units, a shutter, an integrator lens, and a collimation mirror is provided, and light is emitted from the illumination optical system toward a mask that is in close proximity to the substrate. A proximity exposure method for exposing a mask pattern onto a substrate,
Measuring a gap between the mask and the substrate at a plurality of locations in an exposure region by a gap measuring means;
According to each gap measured at a plurality of locations, each of changing the illuminance of the plurality of light source units,
A proximity exposure method characterized by comprising:

  According to the proximity exposure apparatus and the proximity exposure method of the present invention, by controlling the illuminance of the plurality of light source units according to each gap measured at a plurality of locations in the exposure region, the exposure surface by the gap distribution is controlled. The variation in illuminance can be reduced, and the exposure accuracy can be improved.

It is a partial exploded perspective view for demonstrating the division | segmentation successive proximity exposure apparatus which concerns on 1st Embodiment of this invention. It is a front view of the division | segmentation successive proximity exposure apparatus shown in FIG. It is sectional drawing of a mask stage. (A) is a perspective view which shows a workpiece | work stage, (b) is sectional drawing which shows the workpiece | work stage and gap sensor along the IV-IV line of (a). (A) is a front view which shows the light irradiation apparatus of an illumination optical system, (b) is sectional drawing along the VV line of (a), (c) is V 'of (a). It is sectional drawing along the -V 'line. (A) is a front view which shows a cassette, (b) is sectional drawing seen from VI direction of (a), (c) is sectional drawing of the cassette seen from VI 'direction of (a). It is a figure which shows this with an integrator lens. It is an expanded sectional view of the light source part vicinity attached to the cassette. It is a principal part enlarged view which shows the state in which the cassette was attached to the support body. It is the schematic which shows the distance from the output surface of each light source part to the entrance surface of an integrator lens. It is a figure for showing the control composition of each light source part. (A) is a figure which shows the illumination intensity of the lamp | ramp before illumination control, (b) is a figure which shows the gap distribution in the exposure area | region before illumination control. (A) is a figure which shows the illumination intensity of the lamp | ramp after the illumination intensity control based on gap distribution, (b) is a figure which shows the illumination intensity distribution in the exposure area | region after illumination intensity control. (A) is a figure which shows the illumination intensity in the exposure surface of each light source part at the time of radiate | emitting the light of substantially uniform illumination intensity from a light source part, (b) is a figure which shows the image of the whole illumination intensity in an exposure surface. It is. (A) is a figure which shows the illumination intensity in the exposure surface of each light source part at the time of raising the illumination intensity of a part of light source part, (b) is a figure which shows the image of the whole illumination intensity in an exposure surface. . (A) is a perspective view which shows the work stage based on the modification of this embodiment, (b) is sectional drawing which shows the work stage and gap sensor along the XV-XV line | wire of (a). . (A), (b) is a figure which shows arrangement | positioning of the light source part attached to a cassette. It is a figure which shows the flame | frame with which the cassette of Fig.16 (a) was attached. It is a whole perspective view of the proximity scan exposure apparatus concerning 2nd Embodiment of this invention. It is a top view which shows a proximity | contact scanning exposure apparatus in the state which removed upper structures, such as an irradiation part. It is a side view which shows the exposure state in the mask arrangement | positioning area | region of a proximity scan exposure apparatus. (A) is a principal part top view for demonstrating the positional relationship of a mask and an air pad, (b) is the sectional drawing. It is a figure for demonstrating the irradiation part of a proximity scan exposure apparatus. (A) is a front view which shows the light irradiation apparatus of FIG. 22, (b) is sectional drawing along the XXIII-XXIII line of (a).

  Hereinafter, embodiments according to the light irradiation apparatus, the exposure apparatus, and the exposure method of the present invention will be described in detail with reference to the drawings.

(First embodiment)
As shown in FIGS. 1 and 2, the divided successive proximity exposure apparatus PE of the first embodiment includes a mask stage 10 that holds a mask M, a substrate stage 20 that holds a glass substrate (material to be exposed) W, and a pattern. And an illumination optical system 70 that irradiates light for exposure.

  A glass substrate W (hereinafter simply referred to as “substrate W”) is disposed to face the mask M, and a surface (on the opposite surface side of the mask M) for exposing and transferring a pattern drawn on the mask M. A photosensitive agent is applied to the surface.

  The mask stage 10 is a mask stage base 11 in which a rectangular opening 11a is formed at the center, and a mask holding part that is mounted on the opening 11a of the mask stage base 11 so as to be movable in the X axis, Y axis, and θ directions. A mask holding frame 12 and a mask driving mechanism 16 that is provided on the upper surface of the mask stage base 11 and adjusts the position of the mask M by moving the mask holding frame 12 in the X axis, Y axis, and θ directions. .

  The mask stage base 11 is supported by a column 51 standing on the apparatus base 50 and a Z-axis moving device 52 provided at the upper end of the column 51 so as to be movable in the Z-axis direction (see FIG. 2). It is arranged above the stage 20.

  As shown in FIG. 3, a plurality of planar bearings 13 are arranged on the upper surface of the peripheral edge of the opening 11a of the mask stage base 11, and the mask holding frame 12 has a flange 12a provided at the outer peripheral edge of the upper end. It is mounted on the flat bearing 13. As a result, the mask holding frame 12 is inserted into the opening 11a of the mask stage base 11 through a predetermined gap, so that the mask holding frame 12 can move in the X axis, Y axis, and θ directions by the gap.

  A chuck portion 14 that holds the mask M is fixed to the lower surface of the mask holding frame 12 via a spacer 15. The chuck portion 14 is provided with a plurality of suction nozzles 14a for sucking the peripheral portion of the mask M on which the mask pattern is not drawn, and the mask M is not shown in the drawing through the suction nozzle 14a. It is detachably held on the chuck portion 14 by the apparatus. The chuck portion 14 can move in the X axis, Y axis, and θ directions with respect to the mask stage base 11 together with the mask holding frame 12.

  The mask driving mechanism 16 includes two Y-axis direction driving devices 16y attached to one side along the X-axis direction of the mask holding frame 12, and one X-axis attached to one side along the Y-axis direction of the mask holding frame 12. Direction drive device 16x.

  The Y-axis direction driving device 16y is installed on the mask stage base 11, and has a driving actuator (for example, an electric actuator) 16a having a rod 16b that expands and contracts in the Y-axis direction, and a pin support mechanism 16c at the tip of the rod 16b. And a guide rail 16e attached to a side portion of the mask holding frame 12 along the X-axis direction and movably attached to the slider 16d. The X-axis direction drive device 16x has the same configuration as the Y-axis direction drive device 16y.

  In the mask drive mechanism 16, the mask holding frame 12 is moved in the X-axis direction by driving one X-axis direction drive device 16x, and the two Y-axis direction drive devices 16y are driven equally. The mask holding frame 12 is moved in the Y axis direction. In addition, the mask holding frame 12 is moved in the θ direction (rotated about the Z axis) by driving one of the two Y-axis direction driving devices 16y.

  Furthermore, as shown in FIG. 1, an alignment camera 18 for confirming the attachment position of the mask M held by the chuck portion 14 is provided on the upper surface of the mask stage base 11. The alignment camera 18 is held so as to be movable in the X-axis and Y-axis directions via the moving mechanism 19 and is arranged in the mask holding frame 12.

  On the mask holding frame 12, as shown in FIG. 1, aperture blades 38 are provided at both ends in the X-axis direction of the opening 11a of the mask stage base 11 to shield both ends of the mask M as necessary. It is done. The aperture blade 38 is movable in the X-axis direction by an aperture blade drive mechanism 39 including a motor, a ball screw, a linear guide, and the like, and adjusts the shielding area at both ends of the mask M. The aperture blades 38 are provided not only at both ends of the opening 11a in the X-axis direction but also at both ends of the opening 11a in the Y-axis direction.

  As shown in FIGS. 1 and 2, the substrate stage 20 includes a work stage 21 as a substrate holding unit that holds the substrate W, and the work stage 21 with respect to the apparatus base 50 in the X-axis, Y-axis, and Z-axis directions. A moving substrate driving mechanism 22. The work stage 21 detachably holds the substrate W by a vacuum suction mechanism (not shown). The substrate drive mechanism 22 includes a Y-axis table 23, a Y-axis feed mechanism 24, an X-axis table 25, an X-axis feed mechanism 26, and a Z-tilt adjustment mechanism 27 below the work stage 21.

  As shown in FIG. 2, the Y-axis feed mechanism 24 includes a linear guide 28 and a feed drive mechanism 29, and a slider 30 attached to the back surface of the Y-axis table 23 extends 2 on the apparatus base 50. The Y-axis table 23 is driven along the guide rail 31 by a motor 32 and a ball screw device 33 while straddling the guide rail 31 through a rolling element (not shown).

  The X-axis feed mechanism 26 has the same configuration as the Y-axis feed mechanism 24 and drives the X-axis table 25 in the X direction with respect to the Y-axis table 23. Further, the Z-tilt adjustment mechanism 27 has one movable wedge mechanism formed by combining the wedge-shaped moving bodies 34 and 35 and the feed drive mechanism 36 at one end side in the X direction and two at the other end side. Consists of. The feed drive mechanisms 29 and 36 may be a combination of a motor and a ball screw device, or may be a linear motor having a stator and a mover. Further, the number of Z-tilt adjustment mechanisms 27 installed is arbitrary.

  Thereby, the substrate driving mechanism 22 feeds and drives the work stage 21 in the X direction and the Y direction, and moves the work stage 21 in the Z-axis direction so as to finely adjust the gap between the opposing surfaces of the mask M and the substrate W. Fine adjustment and tilt adjustment.

  Bar mirrors 61 and 62 are respectively attached to the X-direction side and the Y-direction side of the work stage 21, and a total of three laser interferometers 63 are provided at the Y-direction end and the X-direction end of the apparatus base 50. , 64, 65 are provided. As a result, the laser light is applied to the bar mirrors 61 and 62 from the laser interferometers 63, 64 and 65, the laser light reflected by the bar mirrors 61 and 62 is received, and the laser light and the laser reflected by the bar mirrors 61 and 62 are received. The position of the substrate stage 20 is detected by measuring interference with light.

  As shown in FIG. 4, the work stage 21 is formed with a plurality of circular grooves 21a opened on the upper surface at a plurality of locations in the exposure region, and in each groove 21a, a mask M and a substrate are formed. A plurality of gap sensors 17 are accommodated as gap measuring means for measuring the gap between the facing surfaces of W. Examples of the gap sensor 17 include an optical transmission type, an eddy current type, and an ultrasonic type.

  As shown in FIGS. 2 and 5, the illumination optical system 70 includes a light irradiation device 80 including a plurality of light source units 73 and a light beam emitted from the plurality of light source units 73, and the illuminance of the incident light. Integrator lens 74 for uniforming the distribution, optical control unit 76 capable of voltage control including switching on / off of the lamp 71 of each light source unit 73, and changing the direction of the optical path emitted from the exit surface of the integrator lens 74 A collimation mirror 77; and an exposure control shutter 78 that is disposed between the plurality of light source units 73 and the integrator lens 74 and controls opening and closing so as to transmit and block the irradiated light. Note that a DUV cut filter, a polarization filter, and a band pass filter may be disposed between the integrator lens 74 and the exposure surface, and the curvature of the mirror can be changed manually or automatically in the collimation mirror 77. A declination angle correction unit may be provided.

  As shown in FIGS. 5 to 7, the light irradiation device 80 includes an ultra-high pressure mercury lamp 71 as a light emitting unit, and a reflecting mirror as a reflecting optical system that emits light with directivity emitted from the lamp 71. 72, a plurality of light source units 73 including a plurality of light source units 73, a plurality of cassettes 81 to which a predetermined number of light source units 73 can be respectively mounted, and a support body 82 to which a plurality of cassettes 81 can be mounted. . As the light emitting unit, an LED may be applied instead of the ultrahigh pressure mercury lamp 71.

In the illumination optical system 70, when a 160 W ultrahigh pressure mercury lamp 71 is used, an exposure apparatus that manufactures a 6th generation flat panel has 374 light source units, and an exposure apparatus that manufactures a 7th generation flat panel. In an exposure apparatus that manufactures 572 light source units and 8th generation flat panels, 774 light source units are required. However, in this embodiment, in order to simplify the description, as shown in FIG. 5, the cassette 81 to which a total of six light source sections 73 in three rows in the α direction and two rows in the β direction are attached is three rows × A description will be given on the assumption that 54 light source sections 73 are arranged in a total of nine rows in three rows. The cassette 81 and the support 82 may have a square shape with the same number of light source portions 73 arranged in the α and β directions, but a rectangular shape with a different number in the α and β directions is applied. Moreover, in the light source part 73 of this embodiment, the opening part 72b of the reflection part 72 is formed in the substantially square shape, and it arrange | positions so that four sides may follow a (alpha) and (beta) direction.

  Each cassette 81 includes a light source support unit 83 that supports a predetermined number of light source units 73, and a concave lamp pressing cover 84 that is attached to the light source support unit 83 by pressing the light source unit 73 supported by the light source support unit 83. Are formed in a substantially rectangular parallelepiped shape having the same configuration.

  The light source support portion 83 is provided corresponding to the number of the light source portions 73 and is provided on the cover side of the window portions 83 a that emit light from the light source portion 73. A lamp recess 83b that surrounds the opening 72a (or the opening of the reflecting mirror mounting portion to which the reflecting mirror 72 is mounted) is formed. A plurality of cover glasses 85 are attached to the window 83a on the side opposite to the cover. In addition, attachment of the cover glass 85 is arbitrary and does not need to be provided.

  The bottom surface of each lamp recess 83b has intersections p between the irradiation surface (here, the opening surface 72b of the reflecting mirror 72) that irradiates light from the light source unit 73 and the optical axis L of the light source unit 73, respectively, α and β. A single curved surface in the direction, for example, a flat surface or a curved surface (in this embodiment, a flat surface) is formed so as to be positioned on the spherical surface r.

  A contact portion 86 that contacts the rear portion of the light source portion 73 is provided on the bottom surface of the lamp pressing cover 84. Each contact portion 86 is provided with an actuator such as a motor or a cylinder, a spring press, screwing, or the like. A configured lamp holding mechanism 87 is provided. As a result, each light source unit 73 fits the opening 72 a of the reflecting mirror 72 into the lamp recess 83 b of the light source support unit 83 and attaches the lamp pressing cover 84 to the light source support unit 83. By pressing the rear part 73, the cassette 81 is positioned. Therefore, as shown in FIG. 6C, the integrator lens 74 into which the light of the predetermined number of light source units 73 is incident from each irradiation surface irradiated with the light of the predetermined number of light source units 73 positioned on the cassette 81. The distance of each optical axis L to the incident surface is substantially constant. Further, in the storage space between the light source support portion 83 and the lamp pressing cover 84, the back surface 72c of the reflecting mirror 72 of the adjacent light source portion 73 is directly opposed, and other than the light source portion 73, the lamp pressing mechanism 87, and the like. Does not block the flow of air in the storage space, and provides good air fluidity.

  The support 82 includes a support body 91 having a plurality of cassette mounting portions 90 to which a plurality of cassettes 81 are attached, and a support cover 92 that is attached to the support body 91 and covers the rear portion of each cassette 81. Have.

  As shown in FIG. 8, each cassette mounting portion 90 is formed with an opening 90 a where the light source support 83 faces, and a rectangular plane around the light source support 83 is opposed to the periphery of the opening 90 a. A cassette recess 90c having a bottom surface 90b is formed. A cassette fixing means 93 for fixing the cassette 81 is provided around the cassette concave portion 90c of the support body 91. In this embodiment, the cassette fixing means 93 is engaged with the concave portion 81a formed in the cassette 81. Then, the cassette 81 is fixed.

  Each plane 90b of the cassette recesses 90c arranged in the α direction or the β direction has an intersection point p between the irradiation surface that irradiates the light of all the light source parts 73 of each cassette 81 and the optical axis L of the light source part 73. , Β are formed so as to intersect at a predetermined angle γ so as to be positioned on a single curved surface, for example, a spherical surface r (see FIG. 9).

Therefore, each cassette 81 is engaged with the cassette fixing means 93 in the recess 81a of the cassette 81 in a state where the light source support 83 is fitted and positioned in the cassette recess 90c of each cassette mounting portion 90. Each is fixed to the support 82. Then, a support cover 92 is attached to the support body 91 in a state where each cassette 81 is attached to the support body 91. Therefore, as shown in FIG. 9, each irradiation surface irradiated with the light of all the light source units 73 positioned in each cassette 81 and the incident surface of the integrator lens 74 on which the light of the predetermined number of light source units 73 is incident. The distance of each optical axis L is also substantially constant.
In FIG. 9, since the flat surface 90b of the cassette mounting portion 90 is disposed with a predetermined angle, each optical axis L is orthogonal to the flat surface 90b. Therefore, when each optical axis L is extended, each optical axis L to the entrance surface of the integrator lens 74 on which the light of all the light source units 73 is incident intersects with the integrator lens 74.

Further, as shown in FIG. 10, a lighting power source 95 and a control circuit 96 for supplying power to the lamp 71 are individually connected to the light source unit 73 of each cassette 81, and each extending backward from each light source unit 73. The wiring 97 is connected to and integrated with at least one connector 98 provided in each cassette 81. The connector 98 of each cassette 81 and the optical control unit 76 provided outside the support 82 are connected by another wiring 99, respectively. As a result, the optical control unit 76 transmits a control signal to the control circuit 96 of each lamp 71 and performs voltage control for adjusting the voltage including turning on and off the lamp 71.
Note that the lighting power supply 95 and the control circuit 96 of each light source unit 73 may be provided collectively in the cassette 81 or may be provided outside the cassette. Further, the contact portion 86 of the lamp pressing cover 84 is formed so as not to interfere with each wiring 97 from each light source portion 73.
Further, although the lighting power supply 95 and the control circuit 96 are provided for each light source unit 73, one light source unit 73 may be provided for each cassette 81, and each light source unit 73 in the cassette 81 may be managed collectively. .

  In addition, each light source unit 73, each cassette 81, and support 82 of the light irradiation device 80 is provided with a cooling structure for cooling each lamp 71. Specifically, as shown in FIG. 7, a cooling path 75 a is formed in the base part 75 to which the lamp 71 and the reflecting mirror 72 of each light source part 73 are attached, and each cover glass 85 of the cassette 81 includes One or a plurality of through-holes 85a are formed. In addition, a plurality of exhaust holes (communication holes) 84a are formed on the bottom surface of the cassette pressing cover 84 of the cassette 81 (see FIG. 6C), and a plurality of exhaust holes are also formed in the support cover 92 of the support 82. A hole 92a is formed (see FIG. 5C). Further, a blower unit (forced exhaust means) 79 formed outside the support 82 is connected to each exhaust hole 92a via an exhaust pipe 79a. Therefore, by pulling and exhausting the air in the support 82 by the blower unit 79, the external air sucked from the through hole 85a of the cover glass 85 is moved between the lamp 71 and the reflecting mirror 72 in the direction indicated by the arrow. The light sources 73 are passed through the gaps s and guided to a cooling path 75a formed in the base member 75 of the light source unit 73 to cool each light source unit 73 with air.

  In the exposure apparatus PE configured as described above, when the exposure control shutter 44 is controlled to be opened during exposure in the illumination optical system 40, the light emitted from the ultrahigh pressure mercury lamp 71 is incident on the incident surface of the integrator lens 74. Incident. Then, the light emitted from the exit surface of the integrator lens 74 is changed in its traveling direction by the collimation mirror 77 and converted into parallel light. The parallel light is irradiated as pattern exposure light substantially perpendicularly to the surface of the mask M held on the mask stage 10 and the surface of the substrate W held on the substrate stage 20. Is transferred onto the substrate W by exposure.

  Here, in the present embodiment, the plurality of light source units 73 change the illuminance according to each gap measured at a plurality of locations by the plurality of gap sensors 17. Specifically, the gap between the mask M and the substrate W in the exposure region is measured by a plurality of gap sensors 17 arranged on the work stage 21 as shown in FIG. 4, and compared with the set gap. The plurality of light source units 73 partially reduce the illuminance at a portion where the measured gap is narrower than the set gap (that is, set gap−measured value> 0), and the measured gap is wider than the set gap ( In other words, the illuminance is partially increased at the setting gap−measured value <0).

For example, when the gap variation with respect to the set gap as shown in FIG. 11B is measured by the gap sensor 17, the plurality of light source units 73 are changed from the uniform illuminance shown in FIG. The illuminance on the exposure surface corresponding to the gap distribution as shown in FIG. 12B is obtained by changing the illuminance according to the gap distribution shown in FIG. As a result, variation in illuminance on the exposure surface due to variation in gap can be reduced, and the pattern size can be made uniform.
In particular, when a color filter or a TFT substrate of a liquid crystal display panel is formed, the same region of the substrate is overlaid by repeating exposure a plurality of times. Therefore, even when the pattern size is reduced according to the high resolution, the patterns can be superimposed with high accuracy.

For example, as shown in FIG. 13, when light having substantially uniform illuminance is irradiated from four light source units 73 (73 a,..., 73 d), an exposure surface that passes through an integrator lens (fly eye lens) 74. The respective illuminances are uniform, and are made uniform by overlapping these lights. On the other hand, as shown in FIG. 14, when the power of some of the four light source units 73 (73 a, 73 d) is increased, the light from the light source unit 73 passes through the integrator lens (fly eye lens) 74. The illuminance of the light emitted to the exposure surface also increases, and the illuminance on the exposure surface according to the gap distribution can be given.
As a method for controlling the illuminance of the plurality of light source units 73, the light source unit 73 may be controlled for each light source unit 73 or the cassette 81 may be controlled according to the number of the lighting power supply 95 and the control circuit 96 described above. Also good.

  As shown in FIG. 15, the work stage 21 is provided with a plurality of rectangular grooves 21a, and the gap sensor 17 accommodated in each groove 21a is configured to be movable in the grooves 21a. Also good. In this case, each gap sensor 17 measures the gap between the mask M and the substrate W at a plurality of locations in the groove 21a while moving in the groove 21a.

  Further, in the above embodiment, for the sake of simplicity, the cassette 81 in which a total of six light source sections 73, which are arranged in three rows in the α direction and in two rows in the β direction, is described as an example. Eight or more light source parts 73 are arranged in 81, and are attached to the cassette 81 with point symmetry or line symmetry with an arrangement as shown in FIGS. 16 (a) and 16 (b). That is, light sources 73 are arranged in different numbers in the α direction and the β direction, and a line connecting the centers of the light sources 73 located on the outermost periphery attached to the light source support 83 of the cassette 81 with four sides is rectangular. Make. Further, as shown in FIG. 17, the cassette mounting portion 90 of the support 82 to which each cassette 81 is mounted matches the number n (n: a positive integer of 2 or more) arranged in the α and β directions orthogonal to each other. And formed into a rectangular shape. Here, this rectangular shape is most efficient when the number of rows and columns of the cassette is the same as the number of rows and columns of the cassette element.

  The aspect ratio (length / width ratio) of each lens element of the integrator lens 74 is determined corresponding to the aspect ratio of the area of the exposure region. In addition, each lens element of the integrator lens has a structure incapable of capturing light incident from an angle greater than the incident aperture angle. That is, the lens element has a smaller incident aperture angle on the short side than on the long side. For this reason, the aspect ratio (length / width ratio) of the entire light source unit 73 disposed on the support 82 is set to a rectangular shape corresponding to the aspect ratio of the incident surface of the integrator lens 74, so that the light use efficiency is increased. Becomes better.

(Second Embodiment)
Next, a proximity scan exposure apparatus according to a second embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 21, the proximity scan exposure apparatus 101 uses a plurality of masks M on which patterns P are formed for exposure on a substantially rectangular substrate W that is transported in a predetermined direction while approaching the mask M. The pattern L is exposed and transferred onto the substrate W by irradiating the light L. That is, the exposure apparatus 101 employs a scan exposure method in which exposure transfer is performed while the substrate W is moved relative to the plurality of masks M. Note that the size of the mask used in the present embodiment is set to 350 mm × 250 mm, and the X-direction length of the pattern P corresponds to the X-direction length of the effective exposure region.

  As shown in FIGS. 18 and 19, the proximity scan exposure apparatus 101 floats and supports the substrate W, and transports the substrate W in a predetermined direction (X direction in the figure), and a plurality of the substrate scanning mechanisms 120. A mask holding mechanism 170 having a plurality of mask holding portions 171 each holding the mask M and arranged in two rows in a staggered manner along a direction (Y direction in the figure) intersecting with a predetermined direction, and a plurality of mask holding portions 171 is disposed above each of the plurality of irradiation units 180 as an illumination optical system that irradiates the exposure light L, and is disposed between the plurality of irradiation units 180 and the plurality of mask holding units 171. And a plurality of light shielding devices 190 that shield the exposure light L emitted from the light source.

  The substrate transport mechanism 120, the mask holding mechanism 170, the plurality of irradiation units 180, and the light shielding device 190 are disposed on the apparatus base 102 installed on the ground via a level block (not shown). Here, as shown in FIG. 19, the region where the mask holding mechanism 170 is disposed above the region where the substrate transport mechanism 120 transports the substrate W is located upstream of the mask placement region EA and the mask placement region EA. This area is referred to as a substrate carry-in area IA, and an area downstream of the exposure area EA is referred to as a substrate carry-out area OA.

  The substrate transport mechanism 120 is disposed on the carry-in frame 105, the precision frame 106, and the carry-out frame 107 installed on the apparatus base 102 via other level blocks (not shown), and floats the substrate W with air. A floating unit 121 as a substrate holding unit to be supported, and a frame 109 disposed on the apparatus base 102 via another level block 108 on the side of the floating unit 121 in the Y direction, and holds the substrate W And a substrate driving unit 140 for transporting the substrate W in the X direction.

  As shown in FIG. 20, the levitation unit 121 includes a plurality of long exhaust air pads 123 (see FIG. 20) to which a plurality of connecting rods 122 extending upward from the upper surface of the carry-in / out and precision frames 105, 106, 107 are respectively attached. 19), 124 and a plurality of elongated air intake / exhaust air pads 125a and 125b, and an air exhaust system 130 and air exhaust for exhausting air from a plurality of exhaust holes 126 formed in each of the air pads 123, 124, 125a and 125b. And an air suction system 132 and an air suction pump 133 for sucking air from the intake holes 127 formed in the intake / exhaust air pads 125a and 125b.

  The intake / exhaust air pads 125a and 125b have a plurality of exhaust holes 126 and a plurality of intake holes 127, and balance the air pressure between the support surfaces 134 of the air pads 125a and 125b and the substrate W to obtain a predetermined value. The flying height can be set with high accuracy and can be horizontally supported at a stable height.

  As shown in FIG. 19, the substrate driving unit 140 includes a gripping member 141 that grips the substrate W by vacuum suction, a linear guide 142 that guides the gripping member 141 along the X direction, and a gripping member 141 along the X direction. And a drive motor 143 and a ball screw mechanism 144 that are driven in the manner described above, and are attached to the side of the frame 109 in the substrate carry-in area IA so as to be movable in the Z direction and to be rotatable so as to protrude from the upper surface of the frame 109. And a plurality of work collision prevention rollers 145 that support the lower surface of the substrate W waiting to be conveyed to.

  In addition, the substrate transport mechanism 120 is provided in the substrate carry-in side area IA, and the substrate pre-alignment mechanism 150 that performs pre-alignment of the substrate W waiting in the substrate carry-in side area IA, and the substrate alignment mechanism that performs alignment of the substrate W 160.

  As shown in FIGS. 19 and 20, the mask holding mechanism 170 is provided for each of the plurality of mask holding portions 171 and the mask holding portions 171, and the mask holding portion 171 is moved in the X, Y, Z, and θ directions, that is, , A predetermined direction, a crossing direction, a vertical direction with respect to the horizontal plane of the predetermined direction and the crossing direction, and a plurality of mask driving units 172 that drive around a normal line of the horizontal plane.

  The plurality of mask holding portions 171 arranged in two rows in a staggered manner along the Y direction are arranged on the upstream side with a plurality of upstream mask holding portions 171a (six in this embodiment) arranged on the upstream side. A plurality of downstream mask holding portions 171b (six in this embodiment), and the upstream side between column portions 112 (see FIG. 16) erected on both sides in the Y direction of the apparatus base 2. Two main frames 113 installed on the downstream side are respectively supported via a mask driving unit 172. Each mask holding portion 171 has an opening 177 penetrating in the Z direction, and the mask M is vacuum-sucked on the lower surface of the peripheral edge portion.

  The mask drive unit 172 is attached to the main frame 113 and moves along the X direction. The X direction drive unit 173 moves along the X direction. The Z direction drive unit 174 is attached to the tip of the X direction drive unit 173 and drives in the Z direction. A Y-direction drive unit 175 attached to the Z-direction drive unit 174 and driven in the Y-direction, and a θ-direction drive unit 176 attached to the Y-direction drive unit 175 and driven in the θ-direction. A mask holding portion 171 is attached to the tip of 176.

  As shown in FIGS. 22 and 23, the plurality of irradiation units 180 are provided in the housing 181 in the same manner as in the first embodiment, the light irradiation device 80A, the integrator lens 74, the optical control unit 76, and the collimation mirror 77. , And exposure control shutter 78, and plane mirrors 280, 281, 282 disposed between light source unit 73 A and exposure control shutter 78, and between integrator lens 74 and collimation mirror 77. The collimation mirror 77 or the plane mirror 282 as the folding mirror may be provided with a declination angle correction unit that can change the curvature of the mirror manually or automatically.

  The light irradiation device 80A includes a support 82A that includes an ultra-high pressure mercury lamp 71 and a reflecting mirror 72, each of which includes, for example, three cassettes 81A including eight light source sections 73 arranged in four rows and two rows. doing. Similarly to the first embodiment, in the cassette 81A, by attaching the cassette pressing cover 84 to the light source support portion 83 on which the eight light source portions 73 are supported, each irradiation surface irradiated with light from the eight light source portions 73 and The light source unit 73 is positioned so that the distance of each optical axis L to the incident surface of the integrator lens 74 on which the light of the eight light source units 73 is incident is substantially constant. Further, as shown in FIG. 23, each cassette 81A is attached to a plurality of cassette attaching portions 90 of the support 82A, so that each irradiation surface irradiated with light from all the light source portions 73 and the light from the light source portion 73 are obtained. Each cassette 81A is positioned so that the distance of each optical axis L to the incident surface of the integrator lens 74 on which is incident is substantially constant. The wiring arrangement from each light source unit 73 and the cooling structure in the support body are configured in the same manner as in the first embodiment.

  As shown in FIG. 20, the plurality of light shielding devices 190 have a pair of plate-shaped blind members 208 and 209 whose inclination angles are changed, and the blind driving unit 192 changes the inclination angles of the pair of blind members 208 and 209. To do. Thus, in the vicinity of the mask M held by the mask holding unit 171, the exposure light L emitted from the irradiation unit 180 is shielded, and the light shielding width in a predetermined direction for shielding the exposure light L, that is, the Z direction. The projected area viewed from the above can be made variable.

  In the proximity scan exposure apparatus 101, the pair of mask tray units 221 that hold the mask M is driven in the Y direction, so that the masks M held by the upstream and downstream mask holding units 171a and 171b are exchanged. A mask changer 220 is provided and pre-alignment is performed by bringing a positioning pin (not shown) into contact with the mask M while pressing the mask M that is levitated and supported against the mask tray portion 121 before the mask replacement. A mask pre-alignment mechanism 240 is provided.

Further, as shown in FIG. 20, the proximity scanning exposure apparatus 101 includes various detection means such as a laser displacement meter 260, a mask alignment camera (not shown), a tracking camera (not shown), and a tracking illumination 273. Is arranged.
Similarly to the work stage of the first embodiment, grooves are formed in the intake / exhaust air pads 125a and 125b provided in the mask arrangement area (exposure area) EA, and a gap sensor is arranged in the grooves. .

  Next, exposure transfer of the substrate W will be described using the proximity scan exposure apparatus 101 configured as described above. In the present embodiment, when a pattern of R (red), G (green), or B (blue) is drawn on the color filter substrate W on which a base pattern (for example, a black matrix) is drawn. Will be described.

  After the proximity scan exposure apparatus 101 supports the substrate W, which is transported to the substrate carry-in area IA, by air from the exhaust air pad 123 by a loader or the like (not shown) and performs pre-alignment work and alignment work for the substrate W. Then, the substrate W chucked by the gripping member 141 of the substrate driving unit 140 is transferred to the mask arrangement area EA.

  Thereafter, the substrate W moves in the X direction along the rail 142 by driving the drive motor 143 of the substrate drive unit 140. Then, the substrate W is moved onto the exhaust air pad 124 and the intake / exhaust air pads 125a and 125b provided in the mask arrangement area EA, and is lifted and supported with vibrations eliminated as much as possible. When the exposure light L is emitted from the light source in the irradiation unit 180, the exposure light L passes through the mask M held by the mask holding unit 171 and exposes and transfers the pattern onto the substrate W.

  Further, since the exposure apparatus 101 has a follow-up camera (not shown) and a laser displacement meter 260, the relative position deviation between the mask M and the substrate W is detected during the exposure operation, and the detected relative position is detected. Based on the deviation, the mask driving unit 172 is driven to cause the position of the mask M to follow the substrate W in real time. At the same time, the gap between the mask M and the substrate W is detected, the mask driving unit 172 is driven based on the detected gap, and the gap between the mask M and the substrate W is corrected in real time.

  As described above, pattern exposure can be performed on the entire substrate W by performing continuous exposure in the same manner. Since the masks M held by the mask holding part 171 are arranged in a staggered manner, even if the masks M held by the upstream or downstream mask holding parts 171a and 171b are arranged apart from each other, the substrate A pattern can be formed in W without a gap.

  Further, when a plurality of panels are cut out from the substrate W, a non-exposure area where the exposure light L is not irradiated is formed in a corresponding area between adjacent panels. For this reason, during the exposure operation, the pair of blind members 208 and 209 are opened and closed so that the blind members 208 and 209 are positioned in the non-exposure region in the same direction as the substrate W feed direction in accordance with the feed speed of the substrate W. The blind members 208 and 209 are moved.

  Here, also in the proximity scan exposure apparatus as in the present embodiment, the gaps between the mask M and the substrate W in the exposure region are measured at a plurality of locations by the plurality of gap sensors 17, and the plurality of light source units 73 are The illuminance is changed according to each gap. As a result, variation in illuminance on the exposure surface due to variation in gap can be reduced, and the pattern size can be made uniform.

  In the proximity scan exposure apparatus according to the present embodiment, the case where the substrate W is floated and conveyed by air has been described. However, the transport table needs to be configured so that the gap sensor can measure the gap.

  In addition, this invention is not limited to embodiment mentioned above, A deformation | transformation, improvement, etc. are possible suitably.

  For example, the number of light source units 73 arranged in the cassette 81 is eight or more, and the total number of light source units arranged in the support 82 is eight to about 800. If it is about 800, practicality and efficiency are improved. Furthermore, the number of cassettes 81 mounted on the support 82 is preferably 4% or less of the total number of light source units 73. In this case, the number of light source units 73 arranged in one cassette 81 is small. 4% or more.

  Further, for example, in the above-described embodiment, the divided sequential proximity exposure apparatus and the scanning proximity exposure apparatus have been described as the exposure apparatus, but the present invention is not limited thereto, and the present invention is not limited to this, but a mirror projection exposure apparatus and a lens projection exposure apparatus. It can also be applied to a contact type exposure apparatus. In addition, the present invention can be applied to any exposure method such as a batch method, a sequential method, and a scanning method.

10 Mask stage 17 Gap sensor (Gap measuring means)
20 Substrate stage 70 Illumination optical system 71 Lamp 72 Reflecting mirror 73 Light source unit 74 Integrator lens 77 Collimation mirror 78 Exposure control shutter (shutter)
80, 80A Light irradiation device 81, 81A Cassette 82, 82A Support body 101 Proximity scan exposure device (proximity exposure device)
DESCRIPTION OF SYMBOLS 120 Substrate conveyance mechanism 121 Levitation unit 140 Substrate drive unit 170 Mask holding mechanism 171 Mask holding part 172 Mask drive part 180 Irradiation part 190 Shading device M Mask P Pattern PE Sequential proximity exposure apparatus (proximity exposure apparatus)
W Glass substrate (material to be exposed, substrate)

Claims (6)

An illumination optical system having a plurality of light source units, a shutter, an integrator lens, and a collimation mirror is provided, and light is emitted from the illumination optical system toward a mask that is close to and opposed to the substrate. A proximity exposure apparatus that exposes a pattern onto a substrate,
A gap measuring means for measuring a gap between the mask and the substrate at a plurality of locations in an exposure region;
The proximity exposure apparatus, wherein the plurality of light source units change illuminance according to gaps measured at a plurality of locations.   The plurality of light source units may partially decrease illuminance at a location where the measured gap is narrower than a set gap, and partially increase illuminance at a location where the measured gap is wider than a set gap. The proximity exposure apparatus according to claim 1. The proximity exposure apparatus according to claim 2, wherein the gap measuring unit includes a plurality of gap measuring units respectively disposed in a plurality of grooves provided in the work stage . The proximity exposure apparatus according to claim 2, wherein the gap measuring unit is arranged to be movable in a groove provided in a work stage .   The proximity exposure apparatus according to claim 1, wherein the gap measuring unit is a gap sensor. An illumination optical system having a plurality of light source units, a shutter, an integrator lens, and a collimation mirror is provided, and light is emitted from the illumination optical system toward a mask that is close to and opposed to the substrate. A proximity exposure method for exposing a pattern to a substrate,
Measuring a gap between the mask and the substrate at a plurality of locations in an exposure region by a gap measuring means;
According to each gap measured at a plurality of locations, each of changing the illuminance of the plurality of light source units,
A proximity exposure method characterized by comprising:

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