JPH10112579A - Resist exposing method and exposing apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate a pattern mask by inputting a pattern data to a digital micro-mirror device as an electric signal and then inclinedly moving each of a plurality of minute mirrors. SOLUTION: Data of pattern to be formed by CAD is produced and it is then input as an electric signal to a digital micro-mirror device DMD 20. DMD 20 is a space beam modulation element and has many minute mirrors on the surface and the angle of individual minute mirror changes by an electrical signal. Therefore, a plurality of minute mirrors of DMD 20 is inclinedly moves depending on the input pattern data. When a light beam 21 is input to a plurality of minute mirrors, a virtual slice original image A is formed on the mirror surface formed of a plurality of minute mirrors and its reflecting beam is projected on a screen through a projection lens 11 to form an image B corresponding to the resist pattern. Since resist is exposed and sensed only in the image corresponding to the projected pattern, the resist can be exposed sequentially.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for exposing a resist, and more particularly, to a method and an apparatus capable of exposing a resist accurately without using a pattern mask.

[0002]

2. Description of the Related Art Exposure of a resist is used for manufacturing various electrical devices such as a semiconductor device and a printed circuit board. For convenience of explanation, the manufacture of a semiconductor device will be described below as an example.

When manufacturing a semiconductor device, a resist, which is a photosensitive resin film, is formed on a wafer, and the resist is exposed to a desired pattern and exposed to light. In general, implantation or diffusion of impurities is performed.

FIG. 3 shows a conventional exposure apparatus for a semiconductor device. That is, the exposure apparatus employs a structure in which a support table 16 is provided above an XY stage 10 and an optical system 11 and a light source 12 are laid out above the support table 16. When performing exposure, a wafer 13 having a resist formed on its surface is placed on a support table 16, and a pattern mask 14 on which a predetermined pattern is drawn is arranged between a light source 12 and an optical system 11. Light from pattern mask 1
4, and the resist is exposed by reducing and projecting the shape according to the pattern drawn on the pattern mask 14 onto the resist surface. The wafer 13 is moved to the next position by the XY stage 10, and the same operation is performed to perform the next exposure.

[0005]

However, in the conventional exposure method, the precision of the pattern mask is closely related to the quality of the semiconductor device, and the reticle and the master mask are manufactured in a strictly controlled process through a work copy mask. (Pattern mask) had to be produced, and the production of the pattern mask was very complicated. Also, a mask must be manufactured each time a pattern to be formed is different,
There was also a problem that it was difficult to cope with high-mix low-volume production.

SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide an exposure method capable of accurately exposing a resist without using a pattern mask.

[0007]

Therefore, an exposure method according to the present invention creates pattern data corresponding to a pattern to be exposed when exposing a resist formed on a wafer at the time of manufacturing an electrical device. The pattern data is input as an electric signal to a digital micromirror device (hereinafter, referred to as a DMD), the plurality of micromirrors are tilted in accordance with the pattern data, and light is projected on the DMD to generate light from the respective micromirrors. It is characterized in that the reflected light is projected onto a resist to expose the resist in a shape corresponding to the pattern data.

The electrical device referred to in the present invention includes a semiconductor device and a printed circuit board, but also includes other devices manufactured using a resist. Therefore, the wafers include other members having a resist formed on the surface, such as a wafer and a substrate for printing. Since the pattern data is supplied to the DMD as an electric signal, it is preferable to create the pattern data by a processing device built in a computer such as a CAD. The reflected light from the DMD is preferably projected onto the resist as it is, for example, in the case of a printed circuit board adopting the pattern-maximum contact method. It is better to project.

The above-described exposure method can be performed with a relatively simple apparatus such as a light source, a DMD and a support for wafers. That is, according to the present invention, a support for supporting wafers having a resist formed on the surface thereof, and a micro mirror arranged on each memory cell of a two-dimensionally arranged memory array arranged opposite to the support. The plurality of micromirrors are tilted according to the electric signal of the pattern data input to the memory array, and the reflected light from the plurality of micromirrors is supported by the support base. A resist exposure apparatus can be provided that includes a DMD that projects onto a resist on a wafer or the like and exposes the resist to a shape corresponding to the pattern data, and a light source that emits light to a micro mirror of the DMD.

Although the reflected light from the micro mirror of the DMD may be directly projected on the resist surface, it is preferable to provide an optical system in order to improve the imaging accuracy.

[0011]

According to the present invention, since a pattern is directly projected onto a resist by using DMD and exposed, a conventional pattern mask becomes unnecessary and the device manufacturing process is simplified. Not only can you
It is only necessary to create pattern data by DMD for different patterns, and it is possible to easily cope with high-mix low-volume production.
Further, since a complicated process of manufacturing a pattern mask can be omitted, a device manufacturing time can be reduced.

Furthermore, the DMD micromirrors that are currently in practical use have about 1.9 million pixels at intervals of several tens of μm, and are difficult to apply to very high precision semiconductor devices.
The present invention can be applied to the manufacture of a semiconductor device or a printed circuit board with normal accuracy without any problem in accuracy.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to specific examples shown in the drawings. 1 and 2 show a preferred embodiment of the present invention. In the figure, XY stage 1
Numeral 0 is composed of a ball screw and a motor.
High-precision feed is possible in the axial direction. The XY stage 10 has a table (support table) 16 above, on which a wafer 13 having a resist formed on the surface is placed and supported.

A DMD 20 is provided above the XY stage 10.
And the lens system 11 are coaxially arranged in the vertical direction.
The MD2 is configured by arranging about 1.9 million memory cells two-dimensionally to form a memory array, forming aluminum micromirrors on each memory cell, and the micromirror spacing is about 17 μm. Light from the light source 21 is continuously incident on the DMD 20 from obliquely below. A light absorbing plate 22 is arranged on the opposite side of the DMD 20,
This absorbs light other than reflected light necessary for image formation by the DMD 20.

Next, a resist exposure method will be described. FIG. 2 shows the principle of projection of a resist pattern by the DMD 20. First, data of a pattern to be formed by CAD is created, and the pattern data is used as an electrical signal by the DMD.
Enter 20. Here, DMD2 was recently developed,
This is a so-called spatial light modulator, which has a large number of micromirrors on a surface, and the angle of each micromirror changes according to an electric signal. Therefore, each of the plurality of micro mirrors of the DMD 20 tilts according to the input pattern data. When light from the light source 21 is incident on the plurality of minute mirrors, a virtual slice original image A is formed on a mirror surface composed of the plurality of minute mirrors, and the reflected light is projected on the screen 17 via the projection lens 11. An image B corresponding to the resist pattern is formed.

Therefore, utilizing the above-described principle, an image corresponding to the pattern data is formed on the resist on the surface of the wafer 13 instead of the screen 17. Then, since only the resist corresponding to the projected pattern is exposed and exposed, the XY stage 10 is operated to move the wafer 13 to the next position, and by repeating the same operation, the resist is exposed one after another. it can.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a resist exposure apparatus according to a preferred embodiment of the present invention.

FIG. 2 is a diagram for explaining the principle of the device.

FIG. 3 is a schematic configuration diagram showing a conventional resist exposure apparatus.

[Explanation of symbols]

 Reference Signs List 11 lens system (optical system) 13 wafer 16 table (support base) 20 DMD (digital micromirror device) 21 light source

──────────────────────────────────────────────────の Continued on front page (51) Int.Cl. ⁶ Identification code FI H01L 21/30 519

Claims (4)

[Claims] At the time of manufacturing an electrical device, when exposing a resist formed on a wafer or the like, pattern data corresponding to a pattern to be exposed is created, and the pattern data is input to a digital micromirror device as an electrical signal. Then, the plurality of micromirrors are tilted in accordance with the pattern data, and light is projected on the digital micromirror device, and the reflected light from each of the micromirrors is projected on a resist to form a shape corresponding to the pattern data. A resist exposure method, characterized in that it is performed. 2. A resist exposure method according to claim 1, wherein the reflected light from each micro mirror of said digital micro mirror device is reduced by an optical system or projected onto a resist as it is. 3. A support table for supporting wafers having a resist formed on a surface thereof, and a micromirror disposed on each memory cell of a two-dimensionally arranged memory array arranged opposite to the support table. The plurality of micromirrors are tilted in accordance with the electric signal of the pattern data input to the memory array, and the reflected light from the plurality of micromirrors is reflected on the wafers supported by the support table. A resist exposure apparatus comprising: a digital micromirror device that projects onto a resist to expose a shape corresponding to pattern data; and a light source that emits light to a micromirror of the digital micromirror device. 4. An optical system for reducing and projecting reflected light from said plurality of micromirrors onto said resist.
The resist exposure apparatus according to the above.