JPH06168862A - Semiconductor laser aligner - Google Patents

Abstract

PURPOSE:To provide a semiconductor laser aligner in which aligning time can be shortened greatly by superposing a large number of laser beams emitted from semiconductor lasers while shifting sequentially and projecting the laser beam while moving in the direction perpendicular to the arranging direction of laser beam thereby allowing multibeam alining. CONSTITUTION:Laser beams emitted from semiconductor lasers 2, 2,... are introduced into optical fibers 3, 3,... where the optical axes are substantially parallelized. The laser beams are then overlapped by means of a first condenser lens 4 and converged by means of a second condenser lens 5 and an auto-focus lens 6 before being projected onto an object W to be exposed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor laser exposure apparatus capable of performing multiple beam exposure by using a semiconductor laser and arranging a plurality of laser beams so as to overlap each other in a line.

[0002]

2. Description of the Related Art A conventional semiconductor laser exposure apparatus irradiates a single roll of laser light onto a plate-making roll coated with a silver salt film or a photosensitive film wound on a drum, and main-scans (rotates) the drum or plate-making roll. The single laser beam exposure method is used in which the laser beam is sub-scanned (directly moved) along the drum while being applied, and the exposure operation takes an extremely long time.

[0003]

If the number of laser beams is increased, the time required for the exposure work will be one fraction of the number of laser beams used for single laser beam exposure. Therefore, the number of laser beams can be reduced by using a beam splitter. It is possible to increase. However, since the semiconductor laser has a beam energy much weaker than that of the argon / neon gas laser, it cannot pass through the beam splitter at all. Therefore, it is conceivable to arrange a large number of semiconductor lasers side by side, but the arrangement interval of the semiconductor lasers is too large, and it has not been proposed how to arrange the laser beams so that they are arranged in a row one after another. .

The present invention has been devised in view of the above-mentioned points, and a large number of laser beams can be stacked in a row one after another by using a semiconductor laser, and the laser beams can be irradiated in a direction orthogonal to the array direction. You can move and perform multiple laser beam exposure,
It is an object of the present invention to provide a semiconductor laser exposure apparatus that can significantly reduce the time required for exposure work.

[0005]

As a means for solving the above problems, the present invention provides a scanning table 1 with a required number of semiconductor lasers 2 for emitting laser light to an object W to be exposed.
, Are arranged side by side so that their laser beams are radiated in parallel, and one end portion of the same number of optical fibers 3, 3, ... As the semiconductor lasers 2, 2 ,. · Opposed to the semiconductor laser 2 so that the laser light is introduced by aligning their end faces side by side and aligning their end faces side by side, and the other ends of the optical fibers 3, 3, · · are aligned by aligning their end faces side by side. Further, the first condensing lens 4 is installed at a distance A from the other ends of the optical fibers 3, 3, ... While being kept in close proximity, and further at a distance B from the first condensing lens 4. The second condensing lens 5 is installed, and further, the autofocus lens 6 is installed at a distance C from the second condensing lens 5, and the optical fibers 3, 3,
The distance A from the end face of the other end of the first condenser lens 4 to the first condenser lens 4 is such that the spread of the laser light emitted from the optical fibers 3, 3 ,. Is set so that an appropriate value of the overlap R is generated between the laser beams that are adjacent to each other and reach the distance B between the first condenser lens 4 and the second condenser lens 5. Is
The focal length f1 of the first condensing lens 4 and the focal length f2 of the second condensing lens 5 are set to a sum, and the distance C between the second condensing lens 5 and the autofocus lens 6 is set to , The focal length f2 of the second condenser lens 5 and the focal length f3 of the autofocus lens 6 are set, and the autofocus lens 6 and the exposed object W are set.
Is adjusted so that the scanning table 1 is moved and adjusted in the X-axis direction prior to the exposure so as to match the focal length f3 of the autofocus lens 6, and during the exposure, the autofocus of the autofocus lens 6 is performed. The present invention provides a semiconductor laser exposure apparatus, which is characterized in that the focal length f3 is matched with the function.

[0006]

The scanning table 1 is moved and adjusted in the X-axis direction prior to the exposure to adjust the autofocus lens 6 and the exposed object W.
Is the focal length f3 of the autofocus lens 6
To match. Then, the scanning table 1 is placed on the object W to be exposed.
Scanning in the X-axis direction relative to the semiconductor laser 2,
2, ... Are driven by blinking based on image data, and the laser light emitted from the semiconductor lasers 2, 2, ... Is automatically focused with the optical fiber 3, the first condenser lens 4, the second condenser lens 5, and the like. The object W to be exposed is irradiated with the light through the lens 6. A large number of laser beams emitted in parallel from the semiconductor lasers 2, 2, ... Are circularized into a constant diameter in the process of passing through the optical fibers 3, 3 ,. The divergence angle of the light is increased in the process of radiating the laser light, and when the laser light reaches the center of the wall thickness of the first condenser lens 4, an overlap R of an appropriate value is generated between the laser light and the adjacent laser light. The overlapping arrangement of the laser light is generated by the second condenser lens 5 and the autofocus lens 6.
The object W to be exposed is irradiated with the light after being reduced to a tenth to a few tenths.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a semiconductor laser exposure apparatus of the present invention will be described with reference to FIG. In the figure, the exposed object W is
1 shows a rotary drum wound with a silver salt film or a plate-making roll coated with a photosensitive film. The exposed object W is scanned and rotated by a servo motor (not shown). The scanning table 1 is movable in the X-axis direction approaching and separating from the exposed object W and reciprocally movable in the Y-axis direction parallel to the exposed surface of the exposed object W. The movement of the scanning table 1 in the Y-axis direction is the sub-scanning, and the exposed object W
Each rotation of the laser beam is shifted by about the width of the column. When the object W to be exposed is, for example, an offset lithographic plate, the scanning table 1 is preferably configured as a three-dimensional table. The scanning table 1
Semiconductor lasers 2, 2, ... And optical fibers 3, 3 ,.
The first condenser lens 4, the second condenser lens 5, and the autofocus lens 6 are arranged. The ten semiconductor lasers 2, 2, ... Are provided so as to radiate the laser light in parallel and are fixed by a fixture 7. The semiconductor lasers 2, 2, ... Are arranged in close contact with the laser housing. The optical fibers 3, 3, ... Are semiconductor lasers 2,
The same number as that of the lasers 2, 2, ..., One end of which is aligned side by side with the end faces of the semiconductor lasers 2, 2 ,. The light is introduced, and the other ends thereof are fixed by a fiber fixing tool 9 so that the end faces are aligned side by side and are held in parallel and close to each other. The first condensing lens 4 is supported by a finely adjustable supporter 10 at a distance A from the other ends of the optical fibers 3, 3 ,. The second condenser lens 5 is separated from the first condenser lens 4 by a distance B and is supported by a finely adjustable supporter 11. The autofocus lens 6 is supported by a finely adjustable supporter 12 at a distance C from the second condenser lens 5. The laser light emitted from the semiconductor laser array 2 is transmitted through the optical fiber 3,
.., the first condensing lens 4, the second condensing lens 5, and the autofocus lens 6 are transmitted to irradiate the object W to be exposed. The distance A between the optical fibers 3, 3, ... And the first condenser lens 4 is equal to the semiconductor laser 2a,
Laser light emitted from 2a, ...
In the process of passing through 3, ..., The light diameter is circularized to a constant size, and the divergence angle of the light is increased in the process of radiating toward the first condensing lens 4, so that It is set so that when the center of thickness is reached, an appropriate value of overlap R is generated between adjacent laser beams. The overlap R may be a slight overlap so that the laser beams come into contact with each other, but it is preferably 0.293d at the minimum when the light diameter of the laser beam is d.
It is preferable to cause an overlap of 0.5 d and a maximum of 0.5 d. The distance B between the first condenser lens 4 and the second condenser lens 5 is set to a distance obtained by adding the focal length f1 of the first condenser lens 4 and the focal length f2 of the second condenser lens 5. Has been done. Distance C between the second condenser lens 5 and the autofocus lens 6
Is set to a distance obtained by adding the focal length f2 of the second condenser lens 5 and the focal length f3 of the autofocus lens 6. The distance between the autofocus lens 6 and the object W to be exposed is adjusted by moving the scanning table 1 in the X-axis direction prior to the exposure to obtain a focal length f of the autofocus lens 6.
It is supposed to match 3. The autofocus lens 6 is held by the voice coil or the electrostrictive actuator so as to be position-controlled in the optical axis direction, and during exposure, the autofocus function matches the focal length f3.

Prior to the exposure, the scanning table 1 is moved and adjusted in the X-axis direction so that the distance between the autofocus lens 6 and the object W to be exposed becomes equal to the focal length f of the autofocus lens 6.
Match 3 Then, while the object W to be exposed is scanned and rotated, the scanning table 1 is scanned and moved in the Y-axis direction to drive the semiconductor lasers 2, 2, ... Blinking based on the image data, and the semiconductor lasers 2, 2 ,. The laser light radiated from the optical fiber is introduced into the optical fibers 3, 3, ... And the diameter of the laser light is circularized into a certain size while the laser light passes through the optical fibers 3, 3 ,. The divergence angle of the light is increased in the process of radiating toward the laser beam, and when the laser beam reaches the center of the wall thickness of the first condenser lens 4, an overlap R of an appropriate value is generated between the laser beam and the adjacent laser beam. While the overlapping arrangement of the laser light is maintained, the second condensing lens 5 and the autofocus lens 6 squeeze the light to the object W to be exposed to light by narrowing it down to one tenth or several tenths. When the laser light that reaches the center of the thickness of the first condensing lens 4 is in the overlapping arrangement, the laser lights are overlapped at a position P that is ahead of the first condensing lens 4 by the focal length f1 and further cross. As described above, the focal length f2 of the second condenser lens 5 advances, the light passes through the second condenser lens 5, and then the focal distance f2 of the second condenser lens 5 advances to irradiate the object W to be exposed. Perform exposure. Semiconductor laser 2,
The laser light emitted from 2, ..., Blinks and irradiates the object W to be exposed to expose the image based on the image data.

[0009]

As described above, according to the semiconductor laser exposure apparatus of the present invention, the laser beam emitted from the semiconductor laser is introduced into the optical fiber so that the optical axis intervals are close to each other in parallel, and the first condenser lens is provided. In the overlapping arrangement, the second condensing lens and the autofocus lens are arranged to squeeze the overlapping arrangement and irradiate the object to be exposed. The laser beams can be overlapped with each other one after another, and irradiation can be performed in a direction orthogonal to the arrangement direction of the laser beams to expose a large number of laser beams, and the time required for the exposure operation can be greatly shortened.

[Brief description of drawings]

FIG. 1 is a schematic front view of a semiconductor laser exposure apparatus of the present invention.

[Explanation of symbols]

 W ... Object to be exposed, 1 ... Scanning table, 2 ... Semiconductor laser, 3 ... Optical fiber, 4 ... First condensing lens, 5 ... Second condensing lens, 6 ... Autofocus lens,

Claims (1)

[Claims] 1. A scanning table is provided with a required number of semiconductor lasers for emitting laser light to an object to be exposed, arranged in parallel so that the laser light is emitted in parallel, and one end portion of the same number of optical fibers as the semiconductor lasers are provided. Face the semiconductor laser so that the laser light is introduced by aligning the end faces of the semiconductor lasers side by side and aligning their end faces side by side, and further holding the other end of the optical fiber in parallel and close to each other by aligning their end faces side by side. , A first condensing lens is installed at a distance A from the other end of the optical fiber, and a second condensing lens is installed at a distance B from the first condensing lens. An autofocus lens is installed at a distance C from the condenser lens, and the distance A from the end face of the other end of the optical fiber to the first condenser lens is emitted from the optical fiber. When the spread of the laser light to reach the center of the thickness of the first condensing lens, it is set so as to generate an appropriate value overlap with the adjacent laser light, the first collection The distance B between the optical lens and the second condensing lens is set to a distance obtained by adding the focal length f1 of the first condensing lens and the focal length f2 of the second condensing lens. The distance C between the optical lens and the autofocus lens is set to a distance obtained by adding the focal length f2 of the second condenser lens and the focal length f3 of the autofocus lens, and the distance between the autofocus lens and the exposed object W is set. The distance of X is set on the scanning table 1 prior to exposure.
It is characterized in that it is adjusted in the axial direction so as to match the focal length f3 of the autofocus lens, and during exposure, the focal length f3 is matched by the autofocus function of the autofocus lens. Semiconductor laser exposure device.