JPS59123230A - Device for manufacturing semiconductor element - Google Patents

Abstract

PURPOSE:To prevent the lowering of yield rate due to having a blackspot type defect and an opaque stuck matter generating when a pattern transfer is performed by a method wherein an exposure is performed on the same part located on the surface of a wafer through two or more of photo masks having no blackspot type common defect. CONSTITUTION:The first and the second photomasks 23 and 28 are operated in the form of one body, and narrow-stripped beams of light 22b and 22c are scanned on the whole surface of the first and the second photomasks 23 and 28 and a wafer 27 by performing a scanning operation in synchronization with the first and the second photomasks 23 and 28 and the wafer 27. Also, the same mask pattern is formed on the first photomask 23 and the second photomask 28, and the positions of mirrors 24, 25 and 29 are set in such a manner that the beam of light passed through the first and the second photomasks 23 and 28 will be image-formed overlapping on the wafer 27. Consequently, as there is a very little possibility for existence of a blackspot type defect and an opaque stuck manner at the same part of the first photomask 23 and the second photomask 28, an almost complete exposure can be performed.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a method for transferring a pattern on a mask to a photoresist on a wafer (in this case, the photoresist is prevented from being exposed to light due to the opacity of the opaque material on the mask). This invention relates to a manufacturing device for a half-core element that is designed to prevent lurring.

[Technical background of the invention]

The conventional 14-light system includes a project method and a step repeat method. Here, the project-type feeder device will be explained with reference to FIG. Figure 1 shows a light source that emits ultraviolet SJ. The light 11a from this light source 11 is converted into a band-shaped light Z by Surin l-12.
Zbζ changes.

Then, the beam (, 11b) passes through the beam transmitting part 13a of the photomask 13 and is connected to a lens 141 as a condensing system.
From this, an image is formed on the wafer 15. By scanning the photomask 13 and the wafer 5 synchronously, the band-shaped light 11b can be transmitted to the photomask 1 relative to each other.
3 and the entire surface of the wafer 15 is scanned. and,
A photoresist (not shown) is coated on the wafer 15 by setting the illuminance on the wafer 15 and the scanning speed for scanning the photomask 13 and the wafer 15 synchronously to appropriate values. is exposed to light, and the pattern on the photomask I3 is transferred onto the photoresist. Usually, the same photomask 13 (50 to 10
A pattern formed on a photomask 131 is transferred onto 0 wafers 15.

[Problems with background technology]

Usually, the photomask 13 is one in which a pattern is formed on a glass surface using chromium (Cr).

However, out of 100 pellets on the 13-sided circle of the photomask, for example, 5 pellets (sticky flag spot type defects are present).

In addition, when setting the mask on the exposure device or during the exposure operation, sticky opaque dust (for example, 5 pellets) arrives. Since such black spot defects and opaque dust are transferred onto the wafer 15, 10 out of 100 pellets are defective pellets.However, the normal semiconductor device manufacturing process cL involves, for example, 10 pattern transfer steps, resulting in a yield of 35%.Furthermore, with one photomask, the yield is 35%. A series of tasks (more than 50 to 100
The damage caused was severe because several wafers were processed.

[Purpose of the invention]

This invention was developed in view of the above points, and its purpose is to prevent the reduction in yield that occurs during pattern transfer due to black spot defects and opaque deposits that exist on photomasks. An object of the present invention is to provide an apparatus for manufacturing a semiconductor device.

[Summary of the invention]

The same location on the 9171 surface is exposed through two or more fort masks that do not have a common defect such as a black spot, and the light that passes through each photomask (therefore, the amount of light is 4 times the resist minimum exposure meter Eof). In contrast, there are 20 analogies.
% is set too high.

[Embodiments of the invention]

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

In FIG. 2, 21 is a light source that emits ultraviolet rays. Light 21a from this light source 2 is formed into two band-shaped lights 22b by a slit 22.

Changes to 22c. The band-shaped light 22b passes through the first photomask 230 original transmission part 23a and passes through the mirrors 24 and 25.
The light is reflected by the lens 26 and formed into an image on the wafer 27, for example. This lens 26 is used as a condensing system, and instead of this lens, a condensing system using a concave mirror or a convex mirror may be used. On the other hand, the band-shaped light 2
2C passes through the second photomask 28ρ light transmission part 28b, is reflected at Nζ, 25 and 29ζ, and is reflected by the lens 26.
Due to this, the wafer 27' is attenuated by 1; [7] The first and second photomasks 23 and 28 operate as a unit, and the first and second photomasks 23 and 28 and the wafer 27 are scanned synchronously. As a result, the band-shaped lights 22b and 22C scan the entire surface of the first and di2 photomasks 23 and 28 and the wafer 27. Further, the first photomask 2
3 and the second photomask 28 (the same mask pattern is formed, and the first and second photomask 23
．． The light that passed through the wafer 27 is 2 ζ 2 ζ 2' 5. 29
The position of is set. However, the first photomask 2
．． 3 It is probable that similar black spot defects and opaque deposits are present in the second photomask 28 at the same location as the pellet. Since the amount of light is very small, most of the light is exposed from the second photomask 28G (here, the second photomask 28G).This makes it possible to prevent the generation of defective pellets. In this case, the light passing through the first and second photomasks 23° and 28 is used. For example, 20
% more installed.

In addition, in the above-mentioned example 7, instead of using only one light source 21, two light sources may be used.
For example 1 using two masks, three or more masks may be used to prevent the generation of defective pellets. Further, the present invention is applicable not only to project type exposure apparatuses but also to step repeat type exposure apparatuses.

Here, the effects of the above embodiment will be explained in detail in 1. I will explain this.

For example, if it is assumed that the first photomask 231 has black spot type defects and opaque deposits on 10 out of 100 pellets, and that the size is as large as the knee, then 000 in the conventional device. The yield per pattern transfer process is 90%. Furthermore, when there are 10 pattern transfer steps, the device yield after 10 pattern transfer steps is (0,9)=0.35, that is, 35%.

On the other hand, in the device according to one embodiment of the present invention, the first
photomask 23 and second photomask 28 (same pellet here, Ni black spot l-4'4 at the same position)
The pellet is considered defective only if there are defects or opaque deposits, so the yield per pattern transfer process is 1-(2X
='-) ” = 0.99...9, that is 100
1000 99.99999%, and the device yield after 10 times of 1 yen copying λ\ was 99.99999%, so a remarkable improvement in yield can be expected.

〔Effect of the invention〕

As detailed above (according to @Akira here, when transferring the pattern on the photomask to the photoresist on Ueno 1, two or more photomasks were used, so one of the first) If there is a black spot type defect or opaque deposit on the photomask, the probability that the above defect etc. will be present in the same place on another photomask is small, so the pattern on the photomask can be almost completely covered by the photo on Ueno 1. It can be transferred to a resist.

[Brief explanation of drawings]

Fig. 1 is a diagram showing a conventional semiconductor device manufacturing apparatus k;
The figure shows an apparatus for manufacturing a semiconductor device according to an embodiment of the present invention. 2... Light source, 22... Slit, 23... First photomask, 2G... Lens, 27... To Ueno, 28... Second photomask. Appearance) ＼ (q, % person Patent attorney Takehiko Suzue Figure 1 Figure 2 6ゎ5馨゛゛゛゛　118 Commissioner of the Japan Patent Office Kazuo Wakasugi 1, Indication of the case +i Request 1977 - 2;'),'U 11 0 2 Bow/λ Name of the invention] 1 (Guidance! 4., Shi 2 "Production device 3, correction of the beach (relationship with cows) Patent applicant (307) Tokyo Shiba Yuko, Ki Co., Ltd. 4, 11 people

Claims (1)

[Claims] At least one light source, a slit that converts the light from the light source into a strip of light, and a one-to-one ratio of the light from the light source to the strip of light of the number of bales.
A photomask having an identical pattern is provided correspondingly to each other, and a collar e' that passes through the photomask is
Manufacture of confectionery characterized by having an optical means for forming an image of the light onto a wafer.≠15.