JPH0653113A - Scanning projection aligner - Google Patents

Abstract

PURPOSE:To expose a large substrate easily and to eliminate a pattern distortion caused by yawing and rolling in scanning, in a scanning projection aligner which is used for manufacturing a semiconductor and a substrate of a liquid crystal display. CONSTITUTION:This equipment is constituted of a device for casting light from a light source 8 on a mask 11, two concave mirrors 13 and 15, one plane mirror 12, one convex mirror 14 and one right and left reversal mirror 16. This equipment has a 1:1 erect projection optical system which projects a pattern of the mask 11 on a substrate 17, a mechanism for holding the mask 11 and the substrate 17 without changing a relative position of the two, and a scanning device for letting this holding device make a scanning as one body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a scanning projection exposure apparatus used for manufacturing semiconductors or liquid crystal display device substrates.

[0002]

2. Description of the Related Art Generally, in manufacturing semiconductors, liquid crystal display substrates, etc., exposure processing is performed by a scanning projection exposure apparatus.

FIG. 7 shows a schematic structure of a conventional scanning projection exposure apparatus. Reference numeral 1 in the drawing is an illumination optical system, which is provided with a mercury lamp 1a and various optical parts, and the arc illumination light as shown in FIG. 8 is applied to the mask 2 from the mercury lamp 1a through the arc slit 1b.

The pattern of the mask 2 illuminated in an arc shape is projected on the substrate 6 through a projection optical system composed of a trapezoidal mirror 3, a concave mirror 4 and a convex mirror 5. Therefore, the area of the image projected on the substrate 6 has an arc shape. The mask 2 is provided on the upper end of the carriage 7 and the substrate 6
Is held at the lower end of the carriage 7,
By scanning in the B direction, the entire pattern on the mask 2 is exposed on the substrate 6.

[0005]

However, in the above structure, when exposing a large-sized substrate, a large-sized concave mirror such as a large-diameter concave mirror having a diameter of about twice the width of the substrate is necessary to cover the entire exposure area. Since optical parts are required, it is difficult to manufacture and expensive. Further, since it is an inverted optical system, there is a problem that the yawing and lateral shake of the linear scanning of the carriage cause the pattern distortion of the exposure.

In view of the above problems, the present invention provides a scanning projection exposure apparatus which is easy to manufacture, low in cost, easy to expose a large substrate, and free from yawing of scanning and lateral shake causing pattern distortion. That is the purpose.

[0007]

To achieve the above object, a scanning projection exposure apparatus according to the present invention comprises a light source, a means for irradiating a mask with the light, two concave mirrors, and one plane mirror.
An upright projection optical system for projecting the pattern of the mask onto a substrate, a holding mechanism for holding the mask and the substrate without changing their relative positions, The holding mechanism is configured to include a scanning unit that integrally performs a scanning movement.

[0008]

In the above structure, the mask and the substrate are moved in a scanning manner without changing their relative positions, so that the image of the partial pattern of the mask irradiated with light is projected and exposed at a ratio of 1: 1 over the entire surface of the substrate. Since the 1: 1 erecting projection optical system is used, scanning yawing and lateral shake do not cause pattern distortion.

[0009]

Embodiments of the scanning projection exposure apparatus of the present invention will be described below.
This will be described with reference to FIGS.

FIG. 1 shows a scanning projection exposure apparatus according to the first embodiment of the present invention. 8 in the figure is a mercury lamp as a light source,
A heat ray transmissive elliptical reflecting mirror 9 is associated so as to reflect the light of the mercury lamp 8. The light reflected by the elliptical reflecting mirror 9 is projected onto the mask 11 via the condensing optical system 10. The light including the mask pattern information is reflected by the plane mirror 12, the concave mirror 13, the convex mirror 14, the concave mirror 15,
The image is projected on the substrate 17 via the left / right reversing mirror 16. That is, the above 12 to 16 constitute a 1: 1 erecting projection optical system. In this 1: 1 erecting projection optical system, as shown in FIG. 4, O ₂ is at the center of the radius of curvature r of the convex mirror 14 located on the optical axis 33 of the convex mirror 14, and the concave mirrors 13 and 15 are , The radii of curvature R are equal and the centers of the radii of curvature coincide at the position of O ₁ , but O ₁ is arranged at a position slightly displaced from the optical axis 33 of the convex mirror.

The mask 11 is supported and fixed to a supporting member 18, and the substrate 17 is supported and fixed to a supporting member 19. The support members 18 and 19 are attached to the rotary shaft 2
It is fixed integrally to 0. The rotary shaft 20 is rotatably attached to a carriage 23 by a rotary bearing 22. The rotary shaft 20 is rotated by a motor 21, and the carriage 23 is directly driven in the X direction by another motor 24 via a ball screw 34.

2 is a sectional view taken along the line CC of FIG.
Reference numeral 5 is an illumination spot on the mask 11 irradiated from the condensing optical system 10. FIG. 3 is a diagram for explaining the action of the left-right inverting mirror, and R in FIGS. 2 and 3 is a symbol for expressing the direction of an image in the optical system.

The operation of the scanning projection exposure apparatus configured as above will be described. The light emitted from the mercury lamp 8
The light is condensed by the elliptical reflecting mirror 9 and the condensing optical system 10,
An illumination spot 25 is formed on the lower surface of the mask 11. The light including the mask pattern information in the illumination spot 25 is
Next, the image of the partial pattern of the mask 11 is formed on the upper surface of the substrate 17 after being reflected by the plane mirror 12 and passing through the concave mirror 13, the convex mirror 14, the concave mirror 15, and the left / right reversing mirror 16. At this time, the mask pattern in the illumination spot 25 shown in FIG.
After being reflected by the concave mirror 15, the right and left are inverted as shown in FIG. 3, and the left and right reversing mirror 16 converts the image into an erect image and projects it on the substrate 17. The mask 11 and the substrate 1
7 is integrally supported by the supporting members 18 and 19 and the rotary shaft 20 so that the relative position does not change. The motor 21 is rotationally scanned in the θ direction at the same time as the motor 24.
Is scanned linearly in the X direction. Therefore, the illumination spot 25 scans the entire surface of the mask 11, and the entire pattern of the mask 11 is exposed on the substrate 17. In addition, in this embodiment, as shown in FIGS.
1. It is configured so that a plurality of substrates 17 can be processed at the same time.

Further, as shown in FIG. 4, concave mirrors 13, 1
By slightly shifting the center O ₁ of the radius of curvature 5 from the optical axis of the convex mirror, the astigmatic difference of the projection optical system can be reduced and the depth of focus can be increased.

As described above, according to this embodiment, the light source, the means for irradiating the light on the mask, the two concave mirrors, the one plane mirror, the one convex mirror, and the one left-right reversing mirror are used. 1: 1 erecting projection optical system for projecting the mask pattern onto the substrate, a holding mechanism for holding the mask and the substrate without changing their relative positions, and a rotary scan for integrally scanning the holding mechanism. The provision of the mechanism and the linear scanning mechanism has the following excellent effects.

1) Since the optical parts constituting the projection optical system and the illumination optical system may be small, they are easy to manufacture and inexpensive. 2) The exposure area is not limited to the size of the optical system, and
Since the astigmatic difference is small and the depth of focus is large, projection exposure of a large substrate can be easily performed.

3) Since a plurality of substrates can be processed at one time,
High productivity. 4) Since it is a 1: 1 erecting projection optical system, scanning yawing and lateral shake do not cause exposure pattern distortion.

Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 5 shows a scanning projection exposure apparatus according to the second embodiment of the present invention. In this embodiment, the illumination optical system (8-10) and the 1: 1 erecting projection optical system (12-16) are exactly the same as those in the first embodiment. The characteristic structure of this embodiment is that the mask 26
Using a U-shaped support member that integrally supports the substrate 27 and the substrate 27 without changing their relative positions, a Y stage 29 that is linearly driven in the Y direction of FIG. X stage 3 which is linearly driven in the X direction of 6
1 is provided. Reference numeral 25 in the drawing denotes an illumination spot irradiated on the lower surface of the mask 26.

The operation of the scanning projection exposure apparatus configured as above will be described. Illumination optical system (8-10)
The 1: 1 erecting projection optical system (12 to 16) is exactly the same as in the first embodiment. The mask 26 and the substrate 27 are integrally supported by a supporting member 28 so that their relative positions do not change. The motor 30, the ball screw 35 and the motor 32, and the ball screw 36 are used for Y, X.
Is scanned linearly in the direction. For example, as shown in FIG. 6, X, Y
When the scanning motion is alternately performed in the direction, a spiral scanning is performed, the illumination spot 25 scans the entire surface of the mask 26, and the entire pattern of the mask 26 is exposed on the substrate 27.

As described above, according to this embodiment, the light source 8
And a means for irradiating the light to the mask 26, and a 1: 1 upright projection composed of two concave mirrors 13 and 15, one plane mirror 12, one convex mirror 14 and one left-right reversing mirror 16. The optical system, the holding mechanism that holds the mask 26 and the substrate 27 without changing their relative positions, and the two linear scanning mechanisms that integrally perform the scanning movement of the holding mechanism are provided. In addition to the effects similar to those of the embodiment, there is a peculiar effect that the device can be made small and can be manufactured at low cost even when exposing a large substrate.

In the first and second embodiments, the converging optical system 10 including the elliptical reflecting mirror 9 and the refracting optical system is used to form the illumination spot 25. The point is that the mercury lamp which is the light source is used. The light of No. 8 may be condensed on the lower surfaces of the masks 11 and 26, and the same effect can be obtained by using other optical components.

Further, in the first and second embodiments, the light source is a mercury lamp, but other light sources such as an excimer laser light source, a xenon lamp, and sunlight can achieve the same effect.

In the first and second embodiments, the optical system (8 to 16) is fixed and the masks 11 and 26 and the substrate 1 are fixed.
Although 7 and 27 are integrally moved in a scanning manner, the same effect can be obtained even if the mask and the substrate are fixed and the optical system is moved in a scanning manner.

Further, in the first embodiment, the mask 11 and the substrate 17 are four sets, but this may be one set or a plurality other than four. In addition, in the first and second embodiments, the masks 11 and 26 and the substrates 16 and 27 are mechanically coupled and integrally perform the scanning movement. For example, the scanning movements are separately performed by a plurality of drive systems. Then, the same effect can be obtained even if they are electrically synchronized.

[0025]

As is apparent from the above description of the embodiments, the scanning projection exposure apparatus of the present invention includes a light source, a means for irradiating the mask with the light, two concave mirrors and one plane mirror. 1: 1 erecting projection optical system that is composed of one convex mirror and one left / right reversing mirror and projects the mask pattern onto the substrate,
Since the holding mechanism for holding the mask and the substrate without changing the relative position and the scanning means for integrally performing the scanning movement of the holding mechanism or the optical system, it is possible to configure with a small optical component and easy to manufacture. It is inexpensive and can easily expose a large substrate. Moreover, since a 1: 1 erecting projection optical system is used, an excellent effect that scanning yawing and lateral shake do not cause pattern distortion can be obtained.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a scanning projection exposure apparatus according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line CC of FIG.

FIG. 3 is an explanatory diagram of a left-right reversing mirror.

FIG. 4 is a layout diagram of a concave mirror and a convex mirror.

FIG. 5 is a configuration diagram of a scanning projection exposure apparatus according to a second embodiment of the present invention.

6 is a sectional view taken along the line DD in FIG.

FIG. 7 is a block diagram showing an example of a conventional scanning projection exposure apparatus.

FIG. 8 is a plan view showing the same exposure pattern.

[Explanation of symbols]

 8 Mercury Lamp (Light Source) 11 Mask 12 Plane Mirror 13,15 Concave Mirror 14 Convex Mirror 16 Horizontal Inversion Mirror 17 Substrate 18,19 Supporting Member 23 Carriage

Claims (4)

[Claims] 1. A light source, means for irradiating the light to a mask, two concave mirrors, one plane mirror, one convex mirror and one left-right reversing mirror, and the mask pattern is projected onto a substrate. A scanning projection exposure apparatus comprising a 1: 1 erecting projection optical system, a holding mechanism for holding the mask and the substrate without changing their relative positions, and a scanning means for integrally scanning the holding mechanism or the optical system. 2. In a 1: 1 erecting projection optical system, two concave mirrors are arranged such that their curvatures are equal and their centers of curvature match, and the centers of curvature of said two concave mirrors are not located on the optical axis of the convex mirror. 2. The scanning projection exposure apparatus according to claim 1, wherein the scanning projection exposure apparatus is arranged as described above. 3. The scanning projection exposure apparatus according to claim 1, wherein the scanning means comprises a rotary motion system and a linear motion system. 4. The scanning projection exposure apparatus according to claim 1, wherein the scanning means is composed of two orthogonal linear motion systems.