JP2005300753A - Proximity aligner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a proximity aligner which realizes production of a high-quality exposed product in a short tact even when a relatively inexpensive exposure mask such as a film mask is used. <P>SOLUTION: The proximity aligner E1 exposes a photosensitive substrate 300 along a pattern 200P formed in a mask 200 by disposing the mask 200 in the proximity of the photosensitive substrate 300. The aligner is equipped with a transparent glass plate 400 having a contact flat face 400P as the lower face to which the mask 200 can be tightly adhered, a mask sucking and holding means P1, 401 to suck and hold the mask 200 to the contact face 400P, and a glass plate holding means 31 to hold the transparent glass plate 400 to make a small gap D between the mask 200 and the photosensitive substrate 300. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a proximity exposure apparatus that exposes a pattern formed on an exposure mask to the photosensitive substrate by bringing the exposure mask and the photosensitive substrate close to each other. More specifically, the present invention relates to a proximity exposure apparatus that can realize production of a high-quality exposure product with a short tact even with a relatively inexpensive exposure mask such as a film mask.

  As an exposure apparatus for performing exposure using an exposure mask, an exposure apparatus using a vacuum contact method or a proximity method is known. FIG. 7 is a partial front sectional view of a conventional exposure apparatus. FIG. 7A shows a proximity exposure apparatus, and FIG. 7B shows a vacuum contact exposure apparatus.

  As shown in FIG. 7A, the proximity exposure apparatus 50 includes an exposure mask 51 on which a pattern is formed, a mask holder 52 that holds the exposure mask 51, a photosensitive substrate 53 that is an object to be exposed, and a photosensitive substrate 53. A suction table 54 for sucking and holding is provided. In the proximity exposure apparatus 50, a minute gap D of about 50 to 100 μm is provided between the exposure mask 51 and the photosensitive substrate 53, and exposure is performed with substantially parallel light LT.

  In the proximity exposure apparatus 50, if the minute gap D is not kept constant over the entire exposure area, the pattern width exposed on the photosensitive substrate 53 will vary. Use a mask. Such a glass mask is generally expensive and expensive because it must be prepared for each pattern.

  On the other hand, as shown in FIG. 7B, the vacuum contact exposure apparatus 60 includes a pattern-formed exposure mask 61, a mask holder 62 that holds the exposure mask 61, a photosensitive substrate 63 that is an object to be exposed, and a photosensitive substrate 63. And a sealing member 65 provided between the mask holder 62 and the suction table 64 for forming a sealed space 66. The vacuum contact exposure apparatus 60 performs exposure with substantially parallel light LT in a state where the exposure mask 61 and the photosensitive substrate 63 are in close contact with each other by sucking the sealed space 66 by vacuum.

JP-A-10-268525 JP2004-12777 JP-A-6-295851 JP-A-8-83749

  In the vacuum contact exposure apparatus 60, exposure is performed with the exposure mask 61 and the photosensitive substrate 63 in close contact with each other, so that high resolution can be obtained. However, since vacuum suction and separation of the exposure mask 61 and the photosensitive substrate 63 are performed for each exposure, the tact time becomes longer, and dust carried by the photosensitive substrate 63 adheres to the exposure mask 61 or scratches on the exposure mask 61. The exposure mask 61 has a short life. Therefore, a relatively inexpensive film mask is used as the exposure mask 61, and production of a high-quality exposure product as obtained with the proximity exposure apparatus 50 cannot be expected.

  As described above, the conventional proximity exposure apparatus 50 requires an expensive glass mask for each pattern, and the vacuum contact exposure apparatus 60 has a problem that the tact time becomes long and production of a high-quality exposure product cannot be expected. .

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a proximity exposure apparatus that can realize the production of a high-quality exposure product with a short tact even with a relatively inexpensive exposure mask such as a film mask. And

  In order to solve the above-mentioned problem, as shown in FIGS. 3 and 4, the invention of claim 1 brings a mask 200 and a photosensitive substrate 300 close to each other and causes a pattern 200P formed on the mask 200 to be exposed to the photosensitive material. In the proximity exposure apparatuses 1E and 2E for exposing the substrate 300, the transparent glass plate 400 having a close plane 400P capable of closely contacting the mask 200 on the lower surface, and the mask 200 are attracted and held on the close plane 400P. And the glass plate holding means 31 for holding the transparent glass plate 400 so as to form a minute gap D between the mask 200 and the photosensitive substrate 300.

  According to the invention of claim 1, the transparent glass plate 400 includes a close plane 400 </ b> P capable of closely contacting the mask 200 on the lower surface. Mask suction holding means P1, 401 holds the mask 200 in close contact with the flat surface 400P. The glass plate holding means 31 forms a minute gap D between the mask 200 and the photosensitive substrate 300. Even when the mask 200 is thin and easily bent, for example, when the film mask 200 is used, the influence of the deflection can be eliminated by adsorbing and holding the film mask 200 on the transparent glass plate 400. For this reason, the film mask 200 can be used for high-quality exposure without using a vacuum contact system. Further, since the film mask 200 is adsorbed and held on the transparent glass plate 400, a stable minute gap D can be ensured, and unlike the conventional proximity exposure apparatus, it is not necessary to use an expensive glass mask for each pattern. Further, since it is not necessary to draw a vacuum for each exposure, the tact time can be shortened, and there is no continuous defect due to dust adhesion.

  In the invention of claim 2, as shown in FIGS. 3 and 4, the mask suction holding means includes a mask suction groove 401 formed on the lower surface of the transparent glass plate 400 so as to be outward of the pattern 200P. And suction means P1 for vacuum-sucking a sealed space formed by the mask suction groove 401 and the mask 200.

  According to the invention of claim 2, the mask suction groove 401 is formed on the lower surface of the transparent glass plate 400 so as to be outside the pattern 200 </ b> P. The suction means P1 vacuum-sucks the sealed space formed by the mask suction groove 401 and the mask 200. Thereby, the mask 200 is attracted and held on the transparent glass plate 400. By making the mask suction groove 401 outside the pattern 200P, pattern exposure is not hindered.

  In the invention of claim 3, as shown in FIGS. 5 and 6, the mask suction holding means vacuums the sealed space 401A formed by the mask 200, the transparent glass plate 400A, and the glass plate holding means 31A. It comprises suction means P2 for sucking.

  According to the invention of claim 3, the mask 200, the transparent glass plate 400A, and the glass plate holding means 31A form a sealed space 401A. The sealed space 401A is depressurized by vacuum suction by the suction means P2, and the transparent glass plate 400A is sucked and held by the glass plate holding means 31A. Since the mask suction groove 401 as in the invention of claim 2 is not formed on the transparent glass plate 400A, the labor and cost of processing can be reduced.

  According to the present invention, production of a high-quality exposure product can be realized with a short tact even with a relatively inexpensive exposure mask such as a film mask.

{Embodiment}
FIG. 1 is a schematic view showing a first embodiment of a proximity exposure apparatus according to the present invention, FIG. 2 is an enlarged front partial sectional view showing a mask stage mechanism 4 and a work stage mechanism 5 in FIG. 1, and FIG. FIG. 4 is a partial front sectional view showing the main part of the present invention in the first embodiment, and FIG. 4 is a partial plan sectional view showing the main part of the present invention in the first embodiment.

  As shown in FIG. 1, the proximity exposure apparatus 1E according to the first embodiment includes a feed reel mechanism 1 that sends a strip-shaped workpiece 300 coated with a photoresist, and a take-up reel that winds the strip-shaped workpiece 301 that has been exposed. A mechanism 2, a light irradiation mechanism 3 that is installed between the delivery reel mechanism 1 and the take-up reel mechanism 2 and irradiates exposure light, and a glass jig 400 that holds and holds the film mask 200 on which the pattern 200 </ b> P is formed. A mask stage mechanism 4 that holds the workpiece, a workpiece stage mechanism 5 that holds the strip-shaped workpiece 300 so as to have a predetermined distance from the film mask 200, and a transport mechanism 6 that intermittently transports the strip-shaped workpiece 300 are provided.

  The delivery reel mechanism 1 rotatably supports a reel 310 around which a strip-shaped workpiece 300 coated with a photoresist is wound, and feeds the strip-shaped workpiece 300 at a predetermined speed, a suction box 9, and a fan. 10, the exhaust duct 11, a storage unit 8 that stores the strip-shaped workpiece 300 in a U shape, a roller 12 that guides the strip-shaped workpiece 300 to the storage unit 8, and a feeding unit 13 that feeds the strip-shaped workpiece 300 from the storage unit 8. Prepare.

  The take-up reel mechanism 2 includes a take-up means 14 for taking up the exposed strip-shaped workpiece 301 at a predetermined speed, a suction box 16, a fan 17 and an exhaust duct 18, and a storage means for storing the strip-shaped workpiece 301 in a U-shape. 15, a winding means 19 that rotatably supports a winding reel 320 and winds the belt-like workpiece 301 at a predetermined speed, and a roller 20 that guides the belt-like workpiece 301 from the storage means 15 to the winding means 19 Is provided.

  The light irradiation mechanism 3 includes an ultra-high pressure mercury lamp or an ultra-high pressure xenon mercury lamp, an ultraviolet lamp, a condensing mirror, a reflecting call mirror, an integrator for uniform light distribution, a reflecting call mirror, A collimator lens that converts the light into parallel light, and a case that attaches the collimator lens to a predetermined position.

  As shown in FIG. 2, the mask stage mechanism 4 is installed on a machine base 21 or an XY table installed on the floor, and a machine frame elevating means 22 for elevating the machine frame 23 to a predetermined position, L-shaped guide members 24 and 25 provided at predetermined intervals on the upper part, and L-shaped guide surfaces of the guide members 24 and 25 are supported in a state of slidably contacting each other in a direction perpendicular to the paper surface. Support members 29, 30 and a frame 31 having both ends attached to the support members 29, 30 are provided. A glass jig 400, which is a feature of the present invention, is fixed to the frame 31 by a plurality of bolts 26.

  As shown in FIGS. 3 and 4, the glass jig 400 is a transparent glass plate processed to a size that can be attached to the frame 31. The lower surface, that is, the surface facing the belt-like workpiece 300 is polished so as to be sufficiently flat to form a close contact surface 400P. The close contact plane 400P enables the film mask 200 to contact closely.

  A mask suction groove 401 is formed outside the pattern 200P when the film mask 200 is in close contact with the close contact plane 400P. The mask suction groove 401 is a narrow groove that is continuously formed along the outer edge of the glass jig 400 and has a substantially “mouth” shape in plan view. The mask suction groove 401 is formed outside the pattern 200P so as to surround at least a range larger than the size of the pattern 200P so that the pattern 200P formed on the film mask 200 can be positioned inside the mask suction groove 401. . This does not hinder pattern exposure.

  A vacuum suction hole H1 that penetrates in the thickness direction of the glass jig 400 is formed in the middle of the mask suction groove 401, and a bolt that penetrates in the thickness direction of the glass jig 400 is formed outside the mask suction groove 401. A plurality of holes 402 are formed. The upper surface of the vacuum suction hole H1 is connected to a vacuum pump through a suction pad P1.

  Returning to FIG. 2, the work stage mechanism 5 is installed on the work table 70 on which the suction table 71 for sucking and holding the belt-like work 300 is installed, and on the upstream side and the downstream side of the work table 70. Gap measuring means 74 for measuring the distance between the lower surface of the film mask 200 and the holding surface of the suction table 71; And 77 and a mask frame body elevation adjustment means for adjusting the gap by raising and lowering the frame body 31 based on the measurement results by the gap measurement means 74 to 77.

  It is possible to form the work table 70 and the suction table 71 with one member, or to make the work table 70 move up and down.

  Further, the work table 70 can be installed on an XYθ table that moves in the X and Y directions and rotates in the θ direction on a horizontal plane, and can be configured to move up and down in the Z direction together with the XYθ table.

  The suction table 71 is provided with a suction hole at a predetermined position on the upper surface so that an exhaust means (not shown) having an exhaust fan, an exhaust pipe, a pipe switching valve and the like communicate with the suction hole. Connected.

  When the belt-like workpiece 300 is sucked and held by the suction table 71 of the workpiece stage mechanism 5, the upper surface of the roller 85 is located at the same position as the suction holding surface of the belt-like workpiece 300 of the suction table 71 or below the suction holding surface. To do. When the belt-like workpiece 300 is conveyed, the roller 85 moves to a position where the upper surface of the roller 85 is above the suction holding surface and the upper surface of the belt-like workpiece 300 is not in contact with the film mask 200.

  The gap measuring means 74 to 77 irradiate a line-shaped semiconductor laser beam having a predetermined width toward the lower surface of the film mask 200 and receive reflected light from the lower surface of the film mask 200, and a light reception signal of the sensor. And a calculation unit (not shown) for calculating the gap dimension value. The sensor is attached to a predetermined position of the work table 70 so that the measurement reference position is the suction holding surface of the suction table 71.

  The transport mechanism 6 is installed on the work stage mechanism 5 side of the machine frame 99 and fixed position clamping means 98 having a movable claw for clamping the belt-like workpiece 300, and the rail 100 formed on the machine frame 99 with the belt-like workpiece 300 sandwiched therebetween. A movable clamping unit 101 having a movable claw that is installed so as to move in the conveyance direction of the belt-like workpiece 300 and has a movable claw for clamping the belt-like workpiece 300, and the movable clamping device 101 from the standby position to the conveyance end position, Drive means 102 for reciprocating from the standby position to the standby position.

  The transport mechanism 6 includes a driving roller and a nip roller, and can be configured to intermittently transport the strip-shaped workpiece 300 by sandwiching both ends in the width direction of the strip-shaped workpiece 300. It is preferable to install in place of the take-up means 14.

  In the proximity exposure apparatus 1E configured as described above, the film mask 200 is attached as follows. First, on a flat work table or the like, the glass jig 400 is brought into contact with the film mask 200 so that the mask suction groove 401 of the glass jig 400 enters the inside of the film mask 200 and surrounds the pattern 200P. Next, the vacuum pump is operated to hold the film mask 200 on the glass jig 400 by suction.

  Then, a glass jig 400 holding the film mask 200 by suction is set from below the frame body 31, and the bolts 26 are passed through the bolt holes 402 and fastened to the frame body 31. Finally, the frame body 31 is pushed into a predetermined exposure position. At this time, the supporting members 29 and 30 are pressed by pressing means (not shown), and the supporting members 29 and 30 are positioned and fixed to the guide members 24 and 25.

  After the attachment of the film mask 200 is completed, the exposure operation is started. At the time of exposure, the mask frame lifting / lowering adjusting unit operates so that a minute gap D is formed between the lower surface of the film mask 200 and the exposed surface of the strip-shaped workpiece 300. Since the glass jig 400 is a transparent glass plate, the exposure light is transmitted therethrough, and the strip-shaped workpiece 300 is exposed through the pattern 200P formed on the film mask 200.

  Although the film mask 200 is thin and easily bent, the influence of the bending can be eliminated by being held by suction on the glass jig 400. For this reason, the film mask 200 can be used for high-quality exposure without using a vacuum contact system. Further, since the film mask 200 is attracted and held by the glass jig 400, a stable minute gap D can be secured, so that unlike the conventional proximity exposure apparatus, it is not necessary to use an expensive glass mask for each pattern. Further, since it is not necessary to draw a vacuum for each exposure, the tact time can be shortened, and there is no continuous defect due to dust adhesion. As described above, according to the proximity exposure apparatus 1E, it is possible to produce a high-quality exposure product similar to the conventional proximity exposure apparatus using the relatively inexpensive film mask 200.

  The proximity exposure apparatus 1 </ b> E and the vacuum contact exposure apparatus were subjected to experiments for comparing tact time, resolution degradation, and resolution unevenness. The experimental conditions are as follows. The strip-shaped workpiece 300 has a dry film resist (the dry film thickness is 10 μm, the thickness of the cover film) on the copper side of the copper-clad polyimide formed of polyimide (thickness is 25 μm) and copper (thickness is 8 μm). Used was a laminate of 16 μm (product number SPG102) manufactured by Asahi Kasei Corporation.

As the film mask 200, a PET film having a size of 290 mm × 440 mm × 175 μm was used. The exposure amount was 60 mJ / cm ² . The exposure amount was measured using UVD-365PD manufactured by USHIO INC. Although the exposure machine has a three-line specification with operating wavelengths of g, h, and i, since the sensor is i-line measurement, the actual exposure amount seems to be a little larger. The proximity gap was 50 μm. As a vacuum pump for vacuum contact, KHH-66 (an ultimate pressure of 2 kPa or less, a design displacement of 27.5 liters / minute (60 Hz), 23 liters / minute (50 Hz)) manufactured by Orion Machinery Co., Ltd. was used.

  Since the exposure time varies depending on the sensitivity of the resist, the transfer / vacuum contact time excluding the exposure time is compared with the proximity exposure apparatus 1E and the vacuum contact exposure apparatus. In the Mitty exposure apparatus 1E, the time was halved to 7 seconds. In order to improve the takt time of the vacuum contact exposure apparatus, it is conceivable to increase the capacity of the vacuum pump. However, in this case, there is a problem that the film mask 200 is wrinkled.

In the resolution and resolution unevenness, the proximity exposure apparatus 1E is considered to be inferior, and when the test was performed, the exposure part having a width of 10 μm in the film mask 200 was approximately 10 μm in the vacuum contact exposure apparatus, In the proximity exposure apparatus 1E, the width was as wide as 14 μm. However, the width was stable over the entire exposure surface (380 × 250 mm), and no uneven resolution was observed. When used at L / S (line / space) = 50 μm (pitch 100 μm) or more, it is considered that there is no problem.
{Embodiment 2}
Next, a second embodiment of the proximity exposure apparatus according to the present invention will be described. FIG. 5 is a partial front sectional view showing the main part of the present invention in the proximity exposure apparatus according to the present invention, and FIG. 6 is a plan view showing the main part of the present invention in the second embodiment.

  As shown in FIGS. 5 and 6, the proximity exposure apparatus 2E according to the second embodiment replaces the mask stage mechanism 4 and the glass jig 400 in the proximity exposure apparatus 1E according to the first embodiment, respectively. And a glass jig 400A. The other configuration is the same as that of the proximity exposure apparatus 1E of the first embodiment.

  In the proximity exposure apparatus 2E, as shown in FIG. 5, the frame 31A includes a thick base portion 31A1 and a thin base portion 31A2. A glass suction groove 402A is formed on the lower surface of the thin base portion 31A2 along the outer shape of the lower surface, and a first vacuum suction hole H3 penetrating in the thickness direction is formed from one point of the glass suction groove 402A. A second vacuum suction hole H4 that penetrates in the thickness direction and communicates with a sealed space 401A described later is formed in one of the thick base portions 31A1. The upper surfaces of the first vacuum suction hole H3 and the second vacuum suction hole H4 are connected to a vacuum pump via suction pads P3 and P4, respectively. The first vacuum suction hole H3 and the second vacuum suction hole H4 are configured to be independently vacuum-sucked.

  The glass jig 400A is a transparent glass plate processed to a size that can form a sealed space 401A with the inner peripheral surface of the thick base portion 31A1, and the lower surface is sufficiently polished. Unlike the glass jig 400 of the first embodiment, the mask suction groove 401 and the bolt hole 403 are not formed in the transparent glass plate. This is because the sealed space 401A and the glass suction groove 402A substitute these functions as described below.

  That is, the glass suction groove 402A is decompressed by vacuum suctioning the first vacuum suction hole H3 with the suction pad P3 in a state where the upper surface of the glass jig 400A is in close contact with the lower surface of the thin base portion 31A2. As a result, the vacuum glass jig 400 </ b> A is sucked and held on the frame 31. In addition, the sealed space 401A is depressurized by vacuum suction of the second vacuum suction hole H4 with the suction pad P4 while the upper surface of the film mask 200 is in close contact with the lower surface of the glass jig 400A. Thereby, the film mask 200 is attracted and held by the glass jig 400A.

  Also in the proximity exposure apparatus 2E, the film mask 200 is absorbed and held by the glass jig 400A, so that the influence of the deflection is eliminated. Further, since the film mask 200 is attracted and held by the glass jig 400A, a stable minute gap D can be secured, so that it is not necessary to use an expensive glass mask for each pattern. In addition, since it is not necessary to draw a vacuum for each exposure, the tact time is short, and there is no continuous failure due to dust adhesion. Further, since the mask suction groove 401 and the bolt hole 402 are not formed on the transparent glass plate, it is possible to reduce the labor and cost of processing them as compared with the proximity exposure apparatus 1E of the first embodiment, and to fix the mounting bolts and the like. The number of parts can be reduced.

  In the above embodiment, the proximity exposure apparatuses 1E and 2E are configured to perform exposure processing on a predetermined portion while intermittently transporting the strip-shaped workpiece 300. However, in the present invention, the square or rectangle cut to a predetermined length is used. This single-wafer workpiece can be applied to an exposure apparatus configured to supply the workpiece stage mechanism 5 one by one to perform exposure processing. In addition, the configuration, structure, shape, material, number, etc. of the whole or part of the proximity exposure apparatuses 1E, 2E can be appropriately changed in accordance with the gist of the present invention.

It is the schematic which shows 1st Embodiment of the proximity exposure apparatus which concerns on this invention. FIG. 2 is a partial front sectional view showing a mask stage mechanism and a work stage mechanism in FIG. 1 in an enlarged manner. It is a front fragmentary sectional view which shows the principal part of this invention in 1st Embodiment. It is a plane partial sectional view which shows the principal part of this invention in 1st Embodiment. It is a front fragmentary sectional view which shows the principal part of this invention in 2nd Embodiment. It is a top view which shows the principal part of this invention in 2nd Embodiment. It is a front fragmentary sectional view of the conventional exposure apparatus.

Explanation of symbols

1E Proximity exposure apparatus 2E Proximity exposure apparatus 31 Frame (glass plate holding means)
31A Frame (glass plate holding means)
200 Film mask (mask)
300 Strip work (photosensitive substrate)
400 Glass jig (transparent glass plate)
400A glass jig (transparent glass plate)
400P Close contact plane 401 Mask suction groove 401A Sealed space D Minute gap P1 Suction pad (suction means)
P2 Suction pad (suction means)

Claims (3)

  A proximity exposure apparatus that exposes a pattern formed on the mask to the photosensitive substrate by bringing the mask and the photosensitive substrate close to each other, and a transparent glass plate having a close plane on the lower surface capable of closely contacting the mask; A mask suction holding means for sucking and holding the mask on the intimate plane; and a glass plate holding means for holding the transparent glass plate so as to form a minute gap between the mask and the photosensitive substrate. Proximity exposure apparatus characterized by this.   The mask suction holding means is a suction for vacuum suction of a mask suction groove formed on the lower surface of the transparent glass plate so as to be outside the pattern, and a sealed space formed by the mask suction groove and the mask. The proximity exposure apparatus according to claim 1, comprising: means.   The proximity exposure apparatus according to claim 1, wherein the mask suction holding unit includes a suction unit that vacuum-sucks a sealed space formed by the mask, the transparent glass plate, and the glass plate holding unit.

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