JPH02297920A - Exposure device - Google Patents

Abstract

PURPOSE:To simplify an optical system and to facilitate the exposure of a large-sized board by employing a laser light as an exposure light source, and mounting a XY base in which a mask and a board are moved in two-dimensional manner in a plane perpendicular to a laser light passage. CONSTITUTION:The laser light 2 of a light source 1 is incident to a concave mirror 5 via a mask window 4 of a XY base 3a, reflected on the mirror 5, reflected at convex and concave mirrors 6, 5 near the focal distance, and is incident to the board mounting window of a XY base 3b. The optical axes of the mirrors 6, 7 are parallel to the light 2, and the lights to the windows 3a, 3b are isolated at equal distance (d) from the optical axis. When a XY base motion controller 9 is started, the bases 3a, 3b are moved in +X and Y directions, similarly moved in +Y and -Y directions and swept in two dimensional manner, the pattern 10 of a mask 11 is transferred in a two dimensional manner on the board. According to this structure, the exposure of a large-sized board can be facilitated. Since the exposure light source radiates the laser light, light intensity can be easily increased, and the exposure time can be shortened.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to an exposure apparatus that transfers a copy source pattern formed on a mask onto a substrate (wafer), and is particularly applicable to large substrates. The present invention relates to an exposure apparatus that can easily carry out exposure.

(Prior Art) An exposure apparatus that uses a reflective optical system such as a concave mirror or a convex mirror to project a predetermined pattern on a mask onto a JJ and transfer the pattern onto a substrate is configured as shown in FIG. 7, for example. ing. That is, the light output from the mercury lamp 31 is converted into light having an arcuate cross section using a large number of optical members 32 such as plane mirrors and concave mirrors. Then, this light having an arcuate cross section is irradiated onto a mask 34 mounted on the rear panel 33, and the light transmitted through the mask 34 is reflected by a trapezoidal mirror 35, and the reflected light is transferred to a concave mirror 36 and a convex surface. Re-reflect at 1137. The light re-reflected by the concave mirror 37 is again reflected downward by the trapezoidal mirror 35, and a substrate (wafer) 39 placed on a carrier 38 is interposed in the optical path of this reflected light. Each of the carriers 33, 38 is integrally constructed by a mechanism (not shown), and is supported movably in a plane (horizontal plane) perpendicular to the optical axis by a moving mechanism (not shown).

In addition, an objective lens 40 is provided in front of the mask 34 so that it can be inserted and withdrawn freely, and the operator can check the pattern drawn on the mask 34 through an eyepiece lens 43 via order reflectors 41 and 42 as necessary. The structure is such that it can be done.

In an exposure apparatus having such a structure, the pattern formed on the mask 34 is irradiated with light having an arc-shaped cross section, and the light is irradiated onto the substrate 39, so that an arc-shaped pattern is projected onto the substrate 39. be done. Therefore, carrier 3
3.If 38 is moved horizontally and linearly in one direction,
The two-dimensional pattern drawn on the mask 34 is sequentially centrally copied onto the substrate 39.

However, the exposure apparatus configured as described above still has the following problems. That is, since the carriers 33 and 38 only move linearly, as long as the concave mirror 36 and the convex surface 1137 are used, it is necessary to form the cross-sectional shape of the light irradiated onto the mask 34 into an arc shape. In order to convert the light output from the mercury lamp 31, which is a point light source, into light having an arcuate cross section, it is necessary to use a large number of optical members 32 such as plane mirrors and concave mirrors, as shown in the figure. Therefore, there is a problem that the entire device becomes complicated and large.

Furthermore, since the light passes through a large number of optical members 32, the light intensity is attenuated, and there is also the problem that sufficient exposure intensity cannot be obtained on the substrate 39.

Furthermore, when exposing a substrate 39 having a large area, the original pattern drawn on the mask 34 naturally also becomes large. As a result, it is necessary to increase the cross-sectional area (arc length) of the arc-shaped light, but increasing the cross-sectional area of the light sometimes results in a decrease in the exposure intensity per unit area.

Therefore, there is a certain limit to the size of the substrate 39 that can be exposed with this exposure apparatus.

(Problem to be solved by the invention) - In this way, in conventional exposure apparatuses, exposure is performed using light with an arcuate cross section, so the optical system for forming the light with an arcuate cross section is complicated. Not only that, but when exposing a large substrate, there are cases of underexposure.

The present invention has been made in view of the above circumstances, and uses a laser beam as an exposure light source to attach a mask and a substrate to an XY table that moves two-dimensionally in a plane perpendicular to the optical path of the laser beam. To provide an exposure apparatus that eliminates the need to form the cross section of exposure light into an arc shape, simplifies an optical system, and easily exposes a large substrate without reducing exposure intensity.

[Structure of the invention]

(Means for Solving the Problems) In order to solve the above problems, an exposure apparatus of the present invention includes a laser light source that outputs laser light, an optical axis parallel to the laser light output from the laser light source, and a laser light source that outputs laser light. a concave mirror that reflects the laser beam, and a convex mirror that is placed near the focal point of the concave mirror and that reflects the laser beam reflected by the concave mirror so that it enters the concave mirror. A mask on which a copy source pattern is formed is held so as to be inserted into the optical path of the laser beam from the laser light source to the concave mirror, and the substrate is inserted into the optical path of the laser beam re-reflected by the concave mirror. An XY table is used to hold the mask, and an
This is a table movement control unit.

Further, in another invention, a laser light source that outputs laser light, a first plane mirror that reflects the laser light output from the laser light source in a predetermined direction,
A concave mirror is arranged near the focal point of this concave mirror and reflects the laser light reflected by this concave mirror. a convex mirror for directing +li radiation onto the concave mirror; a second flat mirror for reflecting the laser beam re-reflected by the concave mirror in a direction parallel to the laser beam from the laser light source; A mask, which is movably provided inside and has a copy source pattern formed thereon, is held so as to be inserted in the optical path of the laser light from the laser light source to the first plane mirror, and the substrate is reflected by the second plane mirror. an XY table that is held so as to be inserted into the optical path of the laser beam, and an XY table that transfers the mask pattern onto the substrate by moving this
This is a combination of a table movement control section and a table movement control section.

(Function) With the exposure apparatus configured in this way, the laser light output from the laser light source passes through the pattern drawn on the grid mounted on the XY table and enters the concave mirror, and the concave ILivL The light is reflected by the convex mirror, enters the concave mirror again, and is reflected by the concave mirror again. Finally, the light is irradiated onto the substrate mounted on the XY table. Therefore, the pattern drawn on the mask is projected onto the substrate, and the substrate is exposed. Then, when the XY table movement control section moves the XY table two-dimensionally within the city perpendicular to the laser beam, the pattern drawn on the mask is transferred to the substrate.

Furthermore, in another invention, the laser light output from the laser light source passes through a mask attached to an XY table, and then is bent in a predetermined direction by a first plane mirror and is incident on a concave mirror. Further, the laser beam re-reflected by the concave mirror is bent by a second plane mirror in a direction parallel to the laser beam from the laser light source, and then irradiated onto the substrate mounted on the XY table. Therefore, as described above, when the XY table movement control section moves the XY table two-dimensionally within the city perpendicular to the laser beam, the pattern drawn on the mask is transferred to the substrate.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic diagram showing a schematic configuration of an exposure apparatus according to an embodiment. In the figure, 1 is a laser light source, and this laser light source 1 is
For example, it is composed of an ultraviolet laser oscillator 1a that outputs a pulsed laser beam having a wavelength in the ultraviolet region, and a beam shaping lens IC that shapes the laser beam incident through a reflection film into a beam of light.

Laser light 2 output from laser light source 1 is transmitted through mask mounting window 4 formed on one side of first XY table 3a, and is incident on concave mirror 5. The laser beam 2 incident on one peripheral portion of the concave mirror 5 is reflected by a convex mirror 6 disposed near the focal point of the concave mirror 5, and is again incident on the other peripheral portion of the concave mirror 5. The laser beam reflected again by the concave mirror 5 enters the substrate mounting window 7 formed in the second XY table 3b.

The concave surface fn5 and the convex mirror 6 are arranged so that their optical axes 8 are parallel to the laser beam 2 output from the laser beam k1.1. That is, from the laser light source 1 to the concave surface 11
The laser light incident on the concave mirror 5 is re-reflected from the second laser beam.
The laser beams incident on the substrate mounting window 7 of the XY table 3b maintain a parallel relationship and are spaced from each other by an equal distance 1111d with respect to the optical axis 8. The first and second XY tables 3a and 3b are supported movably in a plane perpendicular to the optical axis 8, and are controlled by an XY table movement control section 9 in the X direction and Y direction in the figure, respectively. Movement is controlled at constant speed.

A mask 11 on which a copy source pattern 10 is drawn is attached to the mask attachment window 4 of the first XY table 3a, as shown in FIG. Attached to 7 is a substrate (U/%) 12 onto which a pattern is to be transferred.

In the exposure apparatus configured in this way, the laser beam 2 output from the laser light source 1 perpendicularly passes through the mask 11, enters the four surfaces 115, is re-reflected by the concave surfaces 115, and then passes through the substrate 12. is irradiated perpendicularly to Therefore, the pattern of the mask 11 is projected onto the substrate 12 and transferred to the substrate 12.

Then, the XY table movement control section 9 is activated, and the first
xy child table a in the (+)X direction in the figure, and the second
If the table 3b is two-dimensionally swept in the XY plane in the (-)X direction and also in the Y direction, the mask 11
The two-dimensional pattern 10 drawn on is two-dimensionally transferred onto the substrate 12.

According to the exposure apparatus configured in this way, the laser light source 1
The cross section of the laser beam 2 outputted from the laser beam 2 is a point (suboso), and there is no need to form it into an arcuate cross section as in the conventional device shown in FIG. Therefore, it is only necessary to incorporate a simple beam shaping lens IC into the laser light source 1, and there is no need to construct a complicated optical system for forming an arcuate cross section unlike the conventional apparatus. As a result, the structure of the optical system can be significantly simplified. Further, complicated adjustment work such as optical axis alignment can be simplified.

Furthermore, since the cross-sectional shape of the laser beam irradiated onto the mask 11 and the substrate 12 is a point (spot), for example, when using light sources with the same light intensity, the exposure intensity per unit area is equal to that of the conventional device. This is significantly greater than the exposure intensity per unit area in an arcuate cross-sectional shape. Therefore, even if a large area pattern is transferred to a large area substrate, the exposure intensity will not decrease.

Therefore, it is possible to expose a large substrate to light.

In addition, since laser light is used as the exposure light source,
Light intensity can be easily increased. As a result, exposure time can be shortened, overall processing time can be shortened, and productivity can be improved.

Furthermore, since pulsed laser light having a wavelength in the ultraviolet region is used, the resolution of the transferred pattern can be significantly improved compared to normal visible light.

In order to improve the work efficiency of exposure, a plurality of laser light sources IA and IB are provided as shown in FIG. It is also possible to irradiate a remote location. In this case, the distances of the laser beams 2A and 2B from the optical axis 8 must be set to the same value d.

In addition, as shown in FIG. 4, one laser beam 2 output from one laser light source IC is transmitted to a plurality of half mirrors
A plurality of laser beams 2B, 2 using 3a, 13b, 13c
It is also possible to irradiate the mask 11 by dividing the radiation into parts b and 2c.

FIG. 5 is a schematic diagram showing an exposure apparatus according to still another embodiment of the present invention. The same parts as in the embodiment of FIG. 1 are given the same reference numerals.

Laser light 2 output from laser light source 1
The light passes vertically through the mask attachment window 4 formed on one side wall of the table 21H, and is bent at a right angle by the first plane mirror 22a attached to one side of the trapezoidal member 22. The laser beam 2 that has been reflected q and l on the first plane VL22a repeats the reflection QJ on the concave mirror 5 and the convex surface VL6, and finally reaches the second plane mirror 22 attached to the other surface of the trapezoidal member 22.
b is reflected in the same direction as the laser beam 2 output from the laser light source 1. The laser beam reflected by the second plane mirror 22b is incident perpendicularly 1 into the substrate mounting window 7 formed in the side wall of the second XY table 211).

The first and second XY tables 21a and 21b are illuminated by laser beams, as shown in the figure. It is supported movably in a plane perpendicular to the laser beam 2 output from fi, 1, and
The table movement control unit 9 controls movement two-dimensionally in the X direction and the Y direction.

Further, a mask 11 on which the original pattern 10 is drawn is attached to the mask attachment window 4 of the first XY table 21a, and a substrate 12 is attached to the substrate attachment window 4 of the second XY table 21b.

Note that the first and second XY tables 21a.

21b. Second plane mirror 22a.

The trapezoidal part +122 to which 22b is attached is fixed to a fixed frame by a support member (not shown), and
It is not linked to the movement of the tables 21a and 21b.

In the exposure apparatus configured in this way, the laser light source 1
The laser beam 2 output from the laser beam 2 perpendicularly passes through the mask 11, is reflected at right angles by the first plane mirror 22a, enters the concave mirror 5, is re-reflected by the concave surface vL5, and then passes through the second plane mirror 22b. After being reflected again in the right angle direction, the substrate 12
is irradiated perpendicularly to. Therefore, the pattern 10 of the mask 11 is projected onto the substrate 12 and transferred to the substrate 12.

Then, the XY table movement control section 9 is activated, and the first
2 in the XY plane shown in the XY table 21a.
The second XY table 21 sweeps dimensionally, and in conjunction with this, the second XY table 21
By sweeping b, the two-dimensional pattern 10 drawn on the mask 11 is two-dimensionally transferred to the substrate 12. Therefore, it is possible to obtain substantially the same effect as the embodiment shown in FIG. 1 described above.

Furthermore, in this embodiment, the sizes of the mask] 1 and the substrate 12 are controlled by the first and second XY tables 21a,
It can be set freely over the movable range of 21b. That is, in the embodiment of FIG. 1, the first and second XY
The sizes of the mask mounting window 4 and the board mounting window 7 formed on the tables 3a and 3b are regulated by the outer diameter dimension of the concave mirror 5, or in this embodiment, the mask mounting window 4 and the board mounting window 7 are Since they are not formed in the same plane, the size of the mask mounting window 4 and the board mounting window 7 is determined by the concave surface ff15.
can be set regardless of the size of the

As a result, a pattern 10 with a large area can be transferred onto a larger substrate 12 without increasing the size of the apparatus.

Note that the present invention is not limited to the embodiments described above. For example, as shown in FIG. 6, it is also possible to use an XY table 3 in which the first XY table 3a and the second XY table 3b in FIG. 1 are integrally formed. In this case, the mask attachment window 4 to which the mask 11 is attached
A first reflecting mirror 25a is disposed in the optical path between the concave mirror 5 and the concave mirror 5, and a second reflecting mirror 25b and a third reflecting mirror m25c are inserted in the optical path between the concave surface 115 and the window 7 with a substrate. I'm letting you do it.

In this way, the three reflecting mirrors 25a reflect the laser beam 2 onto the optical path from the mask 11 to the substrate 12.

By interposing 25b and 25c, the mask 11
Since the images are formed on the substrate 12 as left and right images, the pattern of the mask 11 can be transferred to the substrate 12 while moving the mask 1 and the substrate 12 in the same direction.

[Effects of the Invention] As explained above, according to the exposure apparatus of the present invention, a laser beam is used as an exposure light source, and an XY table that moves a mask and a substrate two-dimensionally in a plane perpendicular to the optical path of the laser beam. It is installed on. Therefore, there is no need to form the cross section of the exposure light into an arc shape, the optical system can be simplified, and large substrates can be easily exposed without reducing the exposure intensity.

[Brief explanation of drawings]

FIG. 1 shows exposure according to the second embodiment of the present invention! A schematic diagram showing the schematic configuration of the A position, FIG. 2 is a diagram showing the mask of the same example,
3 and 4 are diagrams showing main parts of other embodiments of the present invention, FIG. 5 is a schematic diagram showing a schematic configuration of an exposure apparatus according to still another embodiment of the present invention, and FIG. The figure is a schematic diagram showing the main parts of an exposure apparatus according to yet another embodiment of the present invention, and FIG. 7 is a diagram showing a conventional exposure apparatus. 1... Laser light source, 2... Laser light, 3a. 21 a, first XY table, 3b, 21b-.
・TS2 XY table, 4...mask mounting window, 5.
... Concave mirror, 6... Convex mirror, 7... Board mounting window, 8
...Optical axis, 9...XY table movement control unit, 10.
...Pattern, 11...Mask, 12...Substrate, 2
2... Trapezoidal member, 22 a... First plane mirror, 22
b...252 plane mirror. Applicant's agent Patent attorney Takehiko Suzue Figure 3 Figure 4

Claims (2)

[Claims] (1) A laser light source that outputs laser light, a concave mirror whose optical axis is parallel to the laser light output from the laser light source and that reflects the laser light, and a concave mirror that is disposed near the focal point of the concave mirror. a convex mirror that reflects the laser beam reflected by the concave mirror and causes it to re-enter the concave mirror, and a mask that is movably provided in a plane perpendicular to the optical axis and has a copy source pattern formed thereon, from the laser light source to the concave mirror. an XY table that is held so as to be inserted in the optical path of the laser beam to the concave mirror, and a substrate that is held so as to be inserted in the optical path of the laser beam that is re-reflected by the concave mirror; and this XY table is placed on the optical axis. An exposure apparatus comprising: an XY table movement control section that transfers the pattern of the mask onto the substrate by moving it in a perpendicular plane. (2) A laser light source that outputs laser light, a first plane mirror that reflects the laser light output from this laser light source in a predetermined direction, and an optical axis parallel to the laser light reflected by the first plane mirror. A concave mirror that reflects this laser beam, a convex mirror that is disposed near the focal point of this concave mirror and that reflects the laser beam reflected by this concave mirror and makes it re-enter the concave mirror, and a convex mirror that reflects the laser beam again by the concave mirror. a second plane mirror that reflects the generated laser light in a direction parallel to the laser light from the laser light source; and a second plane mirror that is movably provided in a plane orthogonal to the laser light from the laser light source and forms a pattern to be copied. holding the mask so that it is inserted in the optical path of the laser beam from the laser light source to the first plane mirror, and holding the substrate so that it is inserted in the optical path of the laser beam reflected by the second plane mirror. The XY table to hold and this
An exposure apparatus comprising: an XY table movement control section that transfers the pattern of the mask onto the substrate by moving the Y table in the orthogonal plane.