JPH0145626B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of exposing a predetermined mask pattern onto an object to be exposed, such as a semiconductor wafer.

In order to expose the pattern of the mask onto an object to be exposed such as a semiconductor wafer, as shown in FIG. Masks 3 are placed at a certain distance from each other, and light from a light source 4 is irradiated onto the photoreceptor 1 through the mask 3, thereby exposing the pattern of the mask 3 onto the object 2 to be exposed.

Note that 5 in FIG. 1 is a condenser lens.

During this exposure, it is desirable that the light source 4 be a point light source from the perspective of the exposure operation.
In practice, a line light source is used due to its output.

In this way, since the light source 4 is a line light source, the lines of the pattern parallel to the length direction of the line light source are exposed almost accurately, but the lines of the pattern that intersect the length direction of the line light source are exposed almost exactly. , due to the large difference in the angle of incidence of the rays from the line rays incident on this line,
As shown in FIG. 2, the penumbra portion 6 was formed to be large and there was a problem that the width of the pattern could not be accurately exposed.

The present invention was created with the aim of solving the above-mentioned disadvantages in exposure using a line light source.

The present invention will be explained below with reference to the drawings.

In the present invention, light from a line light source 7 is irradiated onto the surface of the photoreceptor 1 by irradiating light from a line light source 7 through a mask 3 which is placed close to and facing an exposed object 2 on which the surface of the photoreceptor 1 is coated. When exposing the object to light, the linear light source 7 is rotated along an imaginary plane parallel to the surface of the photoreceptor 1, about an imaginary vertical line erected approximately at the center of the object 2 to be exposed. This is an exposure method in which the pattern of the mask 3 is exposed onto the surface of the photoreceptor 1 while moving or rotating it.

That is, in FIG. 3, the linear light source body 7 is rotatably provided by an appropriate means, and the exposed body 2, whose surface is coated with the photoreceptor 1,
The mask 3 and lens 5 are arranged in the same manner as in conventional exposure.

If the line light source body 7 is rotated or rotated while maintaining the arrangement shown in FIG. 3, the parallel and intersecting relationship between the pattern lines on the mask 3 and the length direction of the line light source body 7 will disappear, and this Therefore, the variation in the incident light beam from the line light source 7 with respect to the lines of the pattern becomes uniform for all the lines of the pattern, and as a result, exposure with uniform precision can be achieved with fewer penumbras 6.

By the way, the exposed object 2 and the mask 3 of the line light source 7
Various forms of relative rotation or rotation are possible, but when considering cooling and wiring for the line light source 7, repetitive rotation at a rotation angle of 90 degrees or 180 degrees is possible. It is advantageous to let them do so.

In this case, a certain exposure time determined by the material of the photoreceptor 1 is required to complete the exposure of the photoreceptor 1, but within this certain time,
It is necessary to set the rotation speed and period of the line light source 7 so that the posture of the line light source 7 with respect to the lines of an arbitrary pattern is uniform.

In addition, in cases where there is no need to take into consideration cooling and wiring for the linear light source 7, or when a combination of an exposed object 2 and a mask 3, the surface of which is coated with the photoreceptor 1, is rotated with respect to the linear light source 7. If possible, it is preferable to rotate the line light source 7 with respect to the mask 3 at a relatively high speed.

In this way, when the line light source body 7 is continuously rotated with respect to the mask 3, as described above, since exposure requires a certain amount of time, the rotating line light source body 7
becomes a circular surface light source with a diameter equal to the length of the linear light source 7 with respect to the mask 3, and the brightness distribution of this surface light source has a high value at the center and a high value at the periphery, as shown in FIG. As the value decreases as the value approaches You will be able to do that.

In carrying out the present invention described above, the number of linear light sources 7 used is not limited, and two or three may be arranged in parallel,
Further, when a plurality of line light sources are used, each line light source may be arranged in an appropriate arrangement to suit exposure.

Since the irradiation angle of the light from the linear light source with respect to this line can be made uniform for all patterns, the penumbra formed on the photoreceptor can be made extremely small. It exhibits an excellent effect of being able to accurately and uniformly expose the mask pattern onto the photoreceptor.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the basic arrangement of an exposure device. FIG. 2 is a diagram showing a penumbra formed on a photoreceptor by a line light source. FIG. 3 is a diagram showing the basic operation of the present invention. FIG. 4 shows the brightness distribution curve of the light source with respect to the mask when the linear light source body is continuously rotated. Explanation of symbols: 1...photoreceptor, 2...exposed object,
3...mask, 4...light source, 6...penumbra, 7
... Line light source.

Claims (1)

[Claims] 1. When exposing a pattern of the mask onto the surface of the photoreceptor by irradiating light from a light source through a mask that is placed close to and facing the surface of the photoreceptor on an exposed object whose surface is coated with a photoreceptor, A line light source serving as a light source is placed along an imaginary plane parallel to the surface of the photoreceptor, with an imaginary vertical line erected approximately at the center of the exposed object, and the exposed object and the mask. An exposure method in which a pattern of the mask is exposed onto the photoreceptor while rotating or rotating the mask relatively.