JPH10116774A - Method and apparatus for exposure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an exposure method in which an exposure operation can be performed uniformly over the whole face of an exposure region in a proximity exposure method in which a local illuminating operation is scanned so as to expose the whole face of a substrate. SOLUTION: In a proximity exposure method, a substrate 9 and a mask 7 are supported so as to be faced, illuminating light is irradiated from the upper part of the mask 7, and a mask pattern is transferred to a photosensitizer which is coated on the substrate 9. In this case, an illuminating operation is set as a scanning-type local illuminating operation, the cross-sectional shape of a beam by the illuminating light is formed to be a hexagonal shape, the interval between two sides at right angles to the scanning direction of the illuminating operation out of its six sides is adjusted, the luminance of the illuminating light during an exposure operation is measured sequentially by an illuminance sensor 17, and the scanning speed of a local illuminating part 12 is changed sequentially on the basis of its measured result so as to perform the exposure operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an exposure apparatus used in the manufacture of semiconductors and liquid crystal display devices.

[0002]

2. Description of the Related Art Proximity exposure method (proximity exposure method)
That is, an exposure method for supporting a glass substrate or wafer (hereinafter simply referred to as a substrate) coated with a photosensitive agent and a mask in close proximity, and irradiating illumination light from above the mask to transfer a mask pattern to the photosensitive agent. It is. Compared with the projection exposure method, this method does not require a complicated lens system and a high-precision stage, so it is easy to reduce the cost.In comparison with the contact exposure method, the mask and the substrate do not directly contact, so the photosensitive agent peels off It has an excellent feature that defects are unlikely to occur. However, the proximity exposure method is different from the projection exposure method in that it is difficult to adjust the magnification of the exposure pattern according to the extension and contraction of the substrate. Conventionally, as this method, a method of using a scanning type local illumination as illumination light and relatively moving a mask and a substrate in synchronization with the scanning has been considered (for example, Japanese Patent Application No. 6-44051).

Hereinafter, a conventional proximity exposure method and apparatus will be described with reference to FIGS. FIG. 7 is a schematic view of a conventional proximity exposure apparatus. 8 is a detailed view of the local illumination unit, FIG. 9 is a perspective view showing scanning, FIG. 10 is a view of a scanning path, and FIG. 11 is a view showing an integrated exposure amount. In FIG. 7, reference numeral 11 denotes a gantry, and 18 denotes a gantry 11.
An X stage 16 fixed to the X axis guide 18 is slidably mounted on the X axis guide 18 in the X direction and can be driven by an X axis motor (not shown) through a ball screw (not shown).
Reference numeral 15 denotes a Y-axis guide fixed to the X-stage 16, 19 denotes a Y-axis motor fixed to the Y-axis guide, and 13 denotes a slidably mounted to the Y-axis guide 15, and is provided by a Y-axis motor 19 via a ball screw 14. A driven Y stage, 12 is a local illumination unit fixed to the Y stage 13, 5 is a projection lens system including a first lens group 5a and a second lens group 5b, and 4 is a local illumination together with the projection lens system 5. 1 is a mercury lamp, 2 is an elliptical mirror, 3 is an optical fiber fixed at one end to the local illumination unit 12 and the other end is located at the focal point of the elliptical mirror 2, and 6 is local illumination. Aperture mounted at the bottom of part 12, 7
Is a mask, 8 is a mask chuck for holding the mask 7 by suction, 9 is a substrate held opposite to the mask 7, and 25 is a substrate 9
Chuck 10 for sucking and holding XY on gantry 11
XY stage that can move in the direction
Is a setting device for giving a command value to the servo motor driver 23.

The operation of the conventional exposure apparatus configured as described above will be described below. First, scanning exposure using local illumination will be described. In this illumination, the light emitted from the mercury lamp 1 is condensed by the elliptical mirror 2, guided to one end of the optical fiber 3, the light beam emitted from the other end is guided to the optical integrator 4, and reflected in the optical integrator 4 many times. Thereafter, a light beam having a uniform light intensity distribution is prepared at the output end of the optical integrator 4, and an image of the end face is enlarged and projected to the height of the lower surface of the mask 7 by the projection lens system 5, and at the same time, is adjusted to parallel rays. . The parallel light beam having a uniform light intensity distribution obtained in this way is shaped into a hexagon by the aperture 6 attached to the lower surface of the local illumination unit 12 to produce illumination light 38. The pattern on the mask 7 is exposed and transferred over the entire surface of the substrate 9 by scanning the local illuminator 12 above the mask 7 and the substrate 9 facing each other at a constant speed set by a presetter 22 as shown in FIG. it can. FIG. 10 is a diagram showing a scanning path of the illumination light 38 at this time, and FIG. 11 is a diagram showing an integrated exposure amount at a seam portion of the scanning of the illumination light 38. As shown in FIG. 11B, the integrated exposure amount is constant even at the seam of scanning, and uniform exposure can be performed on the entire surface of the substrate. Next, the magnification adjustment will be described.
In this manner, the entire surface of the substrate is exposed by scanning the local illuminator 12, and while the local illuminator scans one line in the Y direction on the substrate, the substrate 9 and the mask 7 are synchronized with the scanning. Error distribution in the Y direction is performed by successively moving the local illuminator in the Y direction, and when the local illumination unit is stepped in the X direction to start a line feed, the relative position between the substrate 9 and the mask 7 is stepwise moved so as to be line by line. By performing the error distribution, the magnification can be adjusted steplessly in the Y direction and stepwise in the X direction.

[0005]

However, in the proximity exposure apparatus having this configuration, since the scanning speed of the local illumination section 12 is constant, the mercury lamp 1 is not exposed during the exposure.
When the brightness of the image changes, uneven exposure occurs. When the photosensitive agent used is a negative type photosensitive agent, the degree of exposure differs between the case where exposure is performed once and the case where exposure is performed twice, even if the integrated exposure amount is the same. There has been a problem that exposure unevenness occurs in portions. This will be described with reference to FIG. FIG. 3 (a)
When exposing and transferring a mask pattern with a fixed line width on a substrate coated with a negative type photosensitive agent, due to the difference in the division ratio of the exposure amount when performing double exposure at various division ratios so that the integrated exposure amount is the same FIG. 4 is a diagram illustrating a difference in exposure line width. The horizontal axis represents the ratio of the first exposure amount to the total exposure amount, and 0 and 10/10 indicate that exposure was performed at once without performing double exposure. FIG. 3B is a diagram showing a change in the exposure line width due to an increase or decrease in the exposure amount in the case of a single exposure. In the case of a negative type photosensitive agent, the exposure line width increases proportionally as the exposure amount increases. It has become. From these figures, it can be seen that even if the integrated exposure amount is the same, the exposure line width becomes narrower when double exposure is performed, resulting in the same state as underexposure. Due to this phenomenon, in the conventional method, exposure unevenness has occurred at a joint portion of scanning exposure.

Accordingly, the present invention solves these problems, and enables magnification adjustment. Even when the brightness of a mercury lamp changes during exposure or when a negative type photosensitive agent is used, the uniformity can be obtained over the entire surface of the substrate. It is an object of the present invention to provide an exposure method and an exposure method that enable exposure transfer.

[0007]

According to a first aspect of the present invention, to solve the above problems, a substrate and a mask are opposed to each other, and a mask pattern is coated on the substrate by irradiating illumination light from above the mask. In the proximity exposure method of transferring to the photosensitive agent, the illumination is a scanning type local illumination, the illuminance of the illumination is sequentially measured during the scanning exposure, and the scanning speed of the local illumination is sequentially adjusted based on the measured value. Then, an exposure method is provided in which the exposure is performed so that the integrated exposure amount becomes a predetermined value for all portions of the exposure area.

According to a second aspect of the present invention, there is provided a proximity exposure method for supporting a substrate and a mask so as to face each other, irradiating illumination light from above the mask, and transferring the mask pattern to a negative type photosensitive agent coated on the substrate. Is a scanning-type local illumination, the cross-sectional shape of the beam emitted from the local illumination is hexagonal, of the six sides, by adjusting the interval between two sides perpendicular to the scanning direction of the local illumination, exposure unevenness. An exposure method is provided, characterized in that the exposure is reduced.

According to a third aspect of the present invention, there is provided a proximity exposure apparatus for supporting a substrate and a mask so as to face each other, irradiating illumination light from above the mask, and exposing and printing a mask pattern on a photosensitive agent applied on the substrate. A local illuminator that scans upwards, an illuminance sensor that sequentially measures the illuminance of illumination light from the local illuminator, and a scanning speed of the local illuminator that is controlled based on an output value of the illuminance sensor and a set value of the integrated exposure amount. An exposure apparatus is provided, comprising:

A fourth aspect of the present invention is a proximity exposure apparatus for supporting a substrate and a mask so as to face each other, irradiating illumination light from above the mask, and exposing and printing a mask pattern on a photosensitive agent applied on the substrate. A local illumination unit that scans upward, an aperture that shapes the cross-sectional shape of the beam by the local illumination unit into a hexagon, and the position of one side of the six sides of the hexagonal beam that is orthogonal to the scanning direction of the local illumination unit. An exposure apparatus comprising: a beam shaping unit that translates in a scanning direction.

[0011]

According to the first aspect of the present invention, the illuminance is sequentially measured during the scanning exposure using the scanning type local illumination, and the illuminance L is measured.
And the scanning speed v such that L / v = constant.
Is adjusted, the integrated exposure amount S = L × d / v becomes constant (d is the beam width in the scanning direction of the local illumination), and the integrated exposure amount can be made uniform over the entire exposure area while using the scanning exposure method.

According to the second aspect of the present invention, the cross-sectional shape of the beam emitted from the local illumination is made hexagonal, and the distance between two sides of the six sides orthogonal to the scanning direction is adjusted, so that the joint of the scanning exposure is formed. By changing the integrated exposure amount in the part,
In scanning exposure using a negative type photosensitive agent, it is possible to reduce exposure unevenness at a joint portion. This will be described with reference to FIGS. As shown in FIG. 3, in order to obtain the same line width as that of single exposure by performing double exposure with a negative type photosensitive agent, the integrated exposure amount must be increased in accordance with the division ratio of double exposure. When the aperture is deformed so that the integrated exposure amount changes at the seam portion of the scanning exposure based on the result, the shape of FIG. 4A is obtained, and the two sides orthogonal to the hexagonal scanning direction shown in FIG. Can be approximated by changing the distance between the pixels, and thereby, exposure unevenness can be reduced. FIGS. 5 and 6 show the integrated exposure amount of the seam portion in each of FIGS. 4A and 4B. As is apparent from these figures, the integrated light amount of the seam portion exposed twice is shown in FIGS. By making the exposure amount larger than that of the other portion exposed once, it is possible to reduce the unevenness in exposure to the negative type photosensitive agent.

According to the third aspect of the present invention, by adopting the above configuration, the illuminance of the illumination light can be sequentially measured during the exposure, and the scanning speed can be adjusted according to the illuminance. An exposure apparatus capable of performing uniform exposure even when it changes can be provided.

According to the fourth aspect of the present invention, one of the six sides of the hexagonal irradiation beam of the local illumination, which is orthogonal to the scanning direction, is moved in parallel in the scanning direction, so that the integrated exposure is performed at the joint portion of the scanning exposure. It is possible to provide an exposure apparatus capable of changing the amount, and capable of uniformly exposing a negative type photosensitive agent over the entire exposure area.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below.
This will be described with reference to the drawings. FIG. 1 is a diagram showing an embodiment of the present invention. FIG. 2 is a detailed view of the local illumination unit in the present embodiment. FIG. 2C is a side view of FIG.
FIG. 2D is a bottom view of FIG.

In FIG. 1, reference numeral 11 denotes a gantry, and 18 denotes a gantry 1.
The X-axis guide fixed to 1, and the X-axis guide 18
An X stage, which is slidably mounted in the direction and can be driven by an X axis motor (not shown) through a ball screw (not shown), 15 is a Y axis guide fixed to an X stage 16, 1
Reference numeral 9 denotes a Y-axis motor fixed to the Y-axis guide. Reference numeral 13 denotes a Y stage, which is slidably mounted on the Y-axis guide 15 and is driven by a Y-axis motor 19 via a ball screw 14.
2 is a local illumination unit fixed to the Y stage 13 and 5 is a first
The projection lens system 4 including the lens group 5a and the second lens group 5b
1 is a mercury lamp, 2 is an elliptical mirror, 3 is an optical fiber fixed at one end to the local illumination unit 12 and the other end is located at the focal point of the elliptical mirror 2, 6 is the local illumination unit 12 , A mask, 8 is a mask chuck for sucking and holding the mask 7, 9 is a substrate held opposite to the mask 7, 25 is a substrate chuck for sucking and holding the substrate 9, 10 is on the gantry 11 Is an XY stage that can move in the XY directions, 17 is an illuminance sensor attached to the local illumination unit 12, 24 is an illuminance sensor amplifier 20, a controller 21, a setting unit 22, and a servo motor driver 23, and one end is an illuminance sensor 17 The other end is control means electrically connected to the Y-axis motor 19. In FIG. 2, reference numeral 30 denotes a plane mirror disposed between the first lens group 5a and the second lens group 5b, 31 denotes a light-shielding plate base attached to the local illumination unit 12, and 33 denotes a light-shielding plate base. Mounted motor, 34
Is a light-shielding plate disposed on the end face of the optical integrator 4 and slidable in the z direction, 32 is a ball screw having one end mounted on the light-shielding plate 34 and the other end mounted on the motor 33, and 35 is the projection end 39 of the optical integrator 4 projected thereon. Projection light 37, a light-shielding area in the optical integrator emission end face 39, 36 is a light-shielded area projection image of the light-shielding area 37, and 38 is illumination light.

The operation of the exposure apparatus configured as described above will be described below. First, the local illumination unit will be described. In this illumination, the light emitted from the mercury lamp 1 was condensed by the elliptical mirror 2, guided to one end of the optical fiber 3, the light flux emitted from the other end was guided to the optical integrator 4, and reflected many times in the optical integrator 4. Thereafter, a light beam having a uniform light intensity distribution is formed at the exit end 39 of the optical integrator 4, and an image of the end surface is projected by the projection lens system 5.
The projection is enlarged to the height of the lower surface of the mask 7 and, at the same time, is adjusted to parallel rays to become projection light 35. And the shading plate 34
Is moved in the z-direction on the light-shielding plate base 31 by the motor 33 via the ball screw 32 to provide a light-shielding area 37 on the emission end face 39 of the optical integrator 4. The light-shielding area 37 is also enlarged and projected by the projection lens system 5. The light-shielded area projected image 36 is obtained. Thus, a part of the projection light 35 is cut off, and the remaining light beam is further transmitted to the aperture 6.
The five sides are cut off to form hexagonal illumination light 38, and illumination light having a shape in which one side of the six sides of the hexagon orthogonal to the scanning direction Y is moved in parallel as shown in FIG. 4B can be formed. . Then, the Y stage 13 supporting the local illumination unit 12 is driven by a Y-axis motor 19 via a ball screw 14 and moved along a Y-axis guide 15 to perform scanning exposure. Even when the integrated exposure amount is increased and a negative type photosensitive agent is used, uneven exposure can be reduced and uniform exposure can be performed over the entire exposure area. Further, during the exposure, the illuminance of the illumination light is sequentially measured by the illuminometer 17, and based on the measured value,
By sequentially controlling the Y-axis motor 19 so that the ratio between the illuminance and the Y-stage speed is always constant, the mercury lamp 1 is exposed during the exposure.
Even if the brightness of the image changes, uniform exposure can be realized over the entire exposure area.

[0018]

According to the first and third aspects of the present invention, the illumination is a scan-type local illumination, the illuminance is sequentially measured during exposure, and the scanning speed is sequentially changed based on the measurement result. Even if the brightness of the mercury lamp changes during exposure, uniform exposure can be performed over the entire exposure area.

According to the second and fourth aspects of the present invention, the illumination is scanning local illumination, the cross-sectional shape of the illumination light beam is hexagonal, and the six sides are orthogonal to the scanning direction of the local illumination. By changing the distance between the two sides, even when exposing a negative type photosensitive agent, uniform exposure can be performed over the entire exposure area.

[Brief description of the drawings]

FIG. 1 is a principle diagram of an exposure apparatus according to an embodiment of the present invention.

FIG. 2 is a detailed view of a local illumination unit of the exposure apparatus according to the embodiment of the present invention.

FIG. 3 is a diagram showing the exposure amount of a negative type photosensitive agent and the change in line width due to double exposure.

FIG. 4 is a diagram of an aperture according to an embodiment of the present invention.

FIG. 5 is a diagram showing an integrated exposure amount at a seam portion of scanning exposure.

FIG. 6 is a diagram showing an integrated exposure amount at a seam portion of scanning exposure according to an embodiment of the present invention.

FIG. 7 is a principle diagram of a conventional exposure apparatus.

FIG. 8 is a detailed view of a local illumination unit of a conventional exposure apparatus.

FIG. 9 is a perspective view showing scanning exposure.

FIG. 10 is a diagram showing a scanning path of scanning exposure.

FIG. 11 is a diagram showing an integrated exposure amount at a seam portion of scanning exposure of a conventional exposure apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mercury lamp 2 Elliptical mirror 3 Optical fiber 4 Optical integrator 5 Projection lens system 6 Aperture 7 Mask 8 Mask chuck 9 Substrate 10 XY stage 11 Mount 12 Local illumination part 13 Y stage 14 Ball screw 15 Y axis guide 16 X stage 17 Illuminance sensor 18 X Axis guide 19 Y-axis motor 20 Illuminance sensor amplifier 21 Controller 22 Setting device 23 Servo driver 24 Control means 25 Substrate chuck 30 Flat mirror 31 Light shielding plate base 32 Ball screw 33 Motor 34 Light shielding plate 35 Projection light 36 Light shielding area projected image 37 Light shielding area 38 Illumination light 39 Optical integrator emission end face

Continued on the front page (72) Inventor Hiroyuki Nagano 1006 Kazuma Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (4)

[Claims] 1. A proximity exposure method in which a substrate and a mask are opposed to each other, and illumination light is irradiated from above the mask to transfer a mask pattern to a photosensitive agent applied on the substrate. During scanning exposure, the illuminance of the illumination is sequentially measured, and the scanning speed of the local illumination is sequentially adjusted based on the measured value, so that the integrated exposure amount becomes a predetermined value for all portions of the exposure region. Exposure method characterized by exposing as follows. 2. A proximity exposure method for supporting a substrate and a mask so as to face each other, irradiating illumination light from above the mask, and transferring a mask pattern to a negative type photosensitive agent applied on the substrate, wherein the illumination is performed in a scanning local area. As illumination, the cross-sectional shape of the beam emitted from the local illumination is hexagonal, and among the six sides, uneven exposure is reduced by adjusting the interval between two sides orthogonal to the scanning direction of the local illumination. Exposure method. 3. In a proximity exposure apparatus for supporting a substrate and a mask so as to face each other and irradiating illumination light from above the mask to expose and print a mask pattern on a photosensitive agent applied on the substrate, a local area above the mask is scanned. An illuminating unit, an illuminance sensor for sequentially measuring the illuminance of illumination light from the local illuminating unit, and a control unit for controlling a scanning speed of the local illuminating unit based on an output value of the illuminance sensor and a set value of the integrated exposure amount. An exposure apparatus, comprising: 4. In a proximity exposure apparatus for supporting a substrate and a mask so as to face each other and irradiating illumination light from above the mask to expose and print a mask pattern on a photosensitive agent applied to the substrate, a local area above the mask is scanned. An illumination unit, an aperture for shaping the cross-sectional shape of the beam by the local illumination unit into a hexagon, and, among the six sides of the hexagonal beam, the position of one side orthogonal to the scanning direction of the local illumination unit is translated in the scanning direction. An exposure apparatus, comprising: a beam shaping unit for causing the beam to be formed.