JPS63133630A - Manufacture of semiconductor element - Google Patents

Abstract

PURPOSE:To eliminate a swollen part of a photosetting photosensitive resin coating film on the circumference part of a semiconductor substrate and improve the pattern resolution of the coating film and, further, utilize the circumference part of the substrate also as a part of a product by developing only the part of the photosetting photosensitive resin coating film on the semiconductor substrate circumference part before development. CONSTITUTION:When photosetting-type photosensitive resin is employed in a photolithography process, a photosetting photosensitive resin film 3 is formed on a semiconductor substrate 1 with a film 2 to be worked between by a spin-coating method and its thick film part 4 on the circumference of the substrate 1 is developed before exposure to dissolve, thus removing the whole or a part of the surface side of the photosensitive resin film 4 on the circumference of the substrate 1. After that, a light 10 is applied to the photosensitive resin film 3 through a photomask 8 which has a required pattern 9 and then the film 3 is developed to form the photosensitive resin film with the required pattern. For instance, developer 6 is dropped onto the swollen part 4 of the photosensitive resin film 3 on the circumference of the substrate 1 while the semiconductor substrate 1 coated with the photosensitive resin film 3 is rotated by a spinner and the surface part of the swollen part 4 is dissolved to reduce its film thickness.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a method for manufacturing a semiconductor device, and particularly to an improvement in an exposure process in a photolithography process used in manufacturing a semiconductor device.

[Conventional technology]

For example, as a method for manufacturing semiconductor elements,
As shown in Japanese Patent No. 979, when a photodegradable photosensitive resin is used in the photolithography process, the photosensitive resin film only around the wafer is irradiated with light and developed, thereby removing the area around the wafer. A desired semiconductor element shape is formed by a first step of dissolving and removing the photosensitive resin film, and by irradiating the photosensitive resin film on the wafer surface with light through a photomask having a desired pattern and performing development. There is a method for manufacturing a semiconductor device including a second step of obtaining a semiconductor device.

However, no consideration was given to the use of a photocurable photosensitive resin and the use of peripheral areas.

Next, the prior art will be explained in more detail using the drawings. FIG. 2(a) is a cross-sectional view of the semiconductor substrate after a photocurable photosensitive resin film is formed on the surface of the semiconductor substrate by spin coating and temporarily cured, where 1 is the semiconductor substrate and 2 is the film to be processed. 3 is a photocurable photosensitive resin film (for example, 0MR83...trade name of Tokyo Ohka Co., Ltd.), 4 is a photosensitive resin film around the semiconductor substrate 1. Expresses excitement. To form this photosensitive resin film, for example, 0MR83 with a viscosity of 35 ep is applied onto a semiconductor substrate while rotating at 300 Orpm, and 85°C
If hot air drying is carried out for 30 minutes, the film thickness will be approximately 1.04 mm, but the photosensitive resin film will bulge around the substrate, and the film thickness will become as thick as 1.2 to 1.3 mm.

Next, as shown in FIG. 2(b), a photomask 8 having a desired pattern 9 is brought into close contact with the photosensitive resin film 3 of the semiconductor substrate 1, and ultraviolet light 1o is irradiated to form the photosensitive resin film 3. 4 is photocured. As is clear from the figure, a non-contact area between the photomask 8 and the photosensitive resin film 3 on the substrate 1 occurs because there is a protrusion 4 of the photosensitive resin film around the semiconductor substrate. It is well known that the pattern resolution is worse in this non-contact area and the surrounding thick film area than in other areas. Although FIG. 2 describes the case where a photocurable photosensitive resin is used, the situation is similar when a photodegradable resin is used.

Below, the conventional technique (see the above-mentioned Japanese Patent Application Laid-open No. 53-55979) that was developed to improve the above-mentioned deterioration in pattern resolution due to the swelling in the peripheral area of the semiconductor substrate will be explained in more detail with reference to FIG. explain. Figure 3 (
a) is a cross-sectional view after a photodegradable photosensitive resin film 3 is formed on the surface of a semiconductor substrate 1 by one rotation coating via an insulating film 2, and there are raised parts of the photosensitive resin film 2 around the substrate 1. 4 is occurring. FIG. 3(b) shows that most of the flat part of the surface of the semiconductor substrate 1 on which the photosensitive resin film 3 is formed is covered with a dark part 9, and at least a raised part 4 around it is covered.
FIG. 3 (Q) shows a state in which the semiconductor substrate is developed and is irradiated with ultraviolet light 10 through a photomask with the region as a bright part. The raised portion 4 of the photosensitive resin film 3 around the photosensitive resin film 1 has been completely removed. FIG. 3(d) shows a state in which a photomask 8 having a desired pattern 9 is brought into close contact with the photosensitive resin film 4 on the semiconductor substrate 1 and ultraviolet light 10 is irradiated thereon. In this case, since the photosensitive resin film 3 on the semiconductor substrate with improved flatness comes into contact with the photomask 8, there is no non-contact part as in the conventional technology, and the photosensitive resin film around the semiconductor substrate is removed. A pattern with uniform dimensions can be obtained in the entire area of the resin film except for the removed area.

[Problem that the invention seeks to solve]

However, the above-mentioned conventional technology cannot be applied when a photocurable photosensitive resin is used, and there is also a problem that the yield is reduced because the peripheral area of the semiconductor substrate cannot be used as a product.

The purpose of the present invention is to eliminate the swelling of the photosensitive resin coating film around the semiconductor substrate and improve the pattern resolution of the coating film when manufacturing semiconductor devices using a photocurable photosensitive resin. Another object of the present invention is to provide a method for manufacturing a semiconductor device in which the peripheral portion of the substrate can also be used as a product.

[Means for solving problems]

The above object is achieved by developing only the peripheral portion of the semiconductor substrate of the photocurable photosensitive resin coating film before exposure.

[For production]

By the above means, the thickness of the raised portion around the semiconductor substrate of the photocurable photosensitive resin film coated on the semiconductor substrate via the processed film is made equal to or less than the thickness of other areas of the film. 6 As a result, when the photomask is brought into close contact with the photosensitive resin film and exposed, the non-contact area between the photosensitive resin film on the semiconductor substrate and the photomask is reduced, and the photosensitive resin film is exposed to light over the entire area of the semiconductor substrate. A pattern of uniform dimensions of the resin film can be obtained.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

FIG. 1(a) is a cross-sectional view showing a state in which a photocurable photosensitive resin film 3 is formed on the surface of a semiconductor substrate 1 via an insulating film 2 by a spin coating method, and the photosensitive resin film is formed on the periphery of the substrate. This shows that a raised portion 4 of No. 3 is generated. In order to form this photosensitive resin film 3, a film having a viscosity of, for example, 35 c
When p photocurable photosensitive resin 0MR83 was spin-coated at 300 rpm and dried with hot air at 85°C for 130 minutes,
The thickness of the photosensitive resin film was about 1.0 mm, but the photosensitive resin film had a swell around the periphery of the substrate 1, and the film thickness became as thick as 1.2 to 1.3 mm.

FIG. 1(b) shows that while the semiconductor substrate 1 having the photosensitive resin film 3 is rotated by a spinner, a developer is dropped only onto the raised portion 4 of the photosensitive resin film 3 around the substrate. To achieve this, for example, use MO as a photosensitive resin.
When using R83, while rotating the semiconductor substrate at 50 rpm, the OMR developer 6 is flowed out from the nozzle 7 only on the raised part of the photosensitive resin film around the substrate, for example, at 1 cc/sec for 5 seconds, and then the OMR developer is 1cc/rinsing liquid
After letting it flow for 10 seconds, spin drying at 4,000 rpm results in a film thickness of 1.2 to 1.2 mm around the substrate.
I was able to reduce my score from 3 to below 1.0.

Next, as shown in FIG. 1(c), a photomask 8 having a desired pattern 9 is brought into close contact with the photosensitive resin film 3 of the semiconductor substrate that has undergone the process shown in FIG. irradiate. In this case, most of the photosensitive resin film on the semiconductor substrate with improved flatness comes into contact with the photomask, so there is no large non-contact area as in the conventional technology, and the dimensions are uniform over the entire area of the semiconductor substrate. pattern can be obtained.

〔Effect of the invention〕

According to the present invention, when a photocurable photosensitive resin is used in a lithography step in a semiconductor device manufacturing method, a photosensitive resin film is formed on a semiconductor substrate by a spin coating method via a processed film. It is possible to eliminate the raised portion around the semiconductor substrate, and further improve the adhesion between the photosensitive resin film and the photomask when the semiconductor substrate having the photosensitive resin film and the photomask are closely exposed. It is possible to obtain a pattern of uniform dimensions of the photosensitive resin film over the entire area of the substrate, and the periphery of the semiconductor substrate, which could not be used with conventional wave technology, can also be used as a product, which also has the effect of improving product yield. be.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of an embodiment of the present invention, and FIGS. 2 and 3 are sectional views of a conventional example. In the figure, 1... Semiconductor substrate 2... Film to be processed 3...
Photosensitive resin film 4... Raised portion of photosensitive resin film 5... Thickness reduced portion of photosensitive resin film 643. Development, rinsing liquid 7... Nozzle 8... Photomask 9... Photomask pattern 10... Ultraviolet light

Claims (1)

[Scope of Claims] 1. When a photocurable photosensitive resin is used in the photolithography process in a semiconductor device manufacturing method, the photosensitive resin is formed on a semiconductor substrate by a spin coating method via a film to be processed. A first step of dissolving and removing all or part of the photosensitive resin film around the semiconductor substrate by developing only the thick part of the resin film around the semiconductor substrate in an unexposed state; A second step of obtaining the photosensitive resin film having the pattern by irradiating the photosensitive resin film on the semiconductor substrate with light through a photomask having a predetermined pattern and then developing it. A method for manufacturing a semiconductor device. 2. In the method for manufacturing a semiconductor device according to claim 1, the method for dissolving and removing a thick portion of the photosensitive resin film formed on the semiconductor substrate is performed while rotating the semiconductor substrate. A method for manufacturing a semiconductor device, characterized in that a developer is supplied only to a peripheral thick part of the film.