JPS59155921A - Formation of resist pattern - Google Patents

Abstract

PURPOSE:To improve the performance of semiconductor elements, magnetic bubble memory elements and to forth manufactured using a resist pattern edge by reducing dullness of said edge by the method wherein surface of a substrate for fabricating resist pattern is coated with resist and is blanched by developing solution for a short time, after which exposure and development are performed. CONSTITUTION:Surface of the substrate is coated with soft-magnetic film 11 such as permalloy and further it is coated with positive resist film 12 of about 7,000Angstrom thick by spin-coating or the like. Next, said surface is blanched by developing solution such as alkaline aqueous solution for 30-90sec to generate a deteriorated layer 13 whose sensitivity to light is inferior to that of the resist film, over the whole surface of the film 12. After that, the substrate is subjected to usual exposure and development to offer a resist pattern 14 in which a left part 12' of the film 12 carrying a left part 13' of the deteriorated layer 13. By this method, when an exposed surface layer of the film 11 is removed by ion- milling, pressure resistance of the pattern increases corresponding to a square- cornered edge 14' and the pattern of 0.8mum wide can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a method for forming a resist pattern, and particularly to a method for reducing drooping of resist pattern edges.

(b) Background of the technology The method of forming various patterns on a substrate using photolithography technology is widely used for semiconductor devices, magnetic bubble memory devices, O-hybrid integrated circuits, etc. With the increase in integration and performance, the patterns formed have become finer. For example, in a magnetic bubble memory element, patterns for generating and transferring bubble domains are required to have widths and intervals of 1 μm or less. In order to form the fine pattern, step 1
A resist pattern with the same shape as ゜ must be formed by exposure and development, but the resist pattern and
It becomes impossible to ignore the f'L of the edge.

(c) Prior art and problems Figure 1 is a typical example of the cross-sectional shape of a positive fine resist pattern formed by a conventional method, observed using a scanning electron microscope. The resist pattern 2 formed in 1. has the above-mentioned sagging in the edge portion 2 of the upper surface.

Therefore, when the quick dew surface layer of the wafer 1 is removed by, for example, ion milling means, the ion milling that removes the &Je of the wafer 1 and also slightly removes the surface layer of the resist pattern 2 can produce a desired etching pattern on the surface of the wafer 1. It had the disadvantage that it was not formed.

In particular, the width of the resist pattern 2 is 1 μm or less, for example, 0 μm or less.
When the thickness becomes about 8 μm, the above-mentioned drawback becomes fatal.

(d) Object of the Invention An object of the present invention is to eliminate the above-mentioned problems and improve the performance of conductor elements, magnetic bubble memory elements, and the like.

(e) 4'4° IJ of the Invention The above object is to deposit a single-core resist film on the surface of a resist pattern forming substrate, expose the surface of the resist film to a developer for an appropriate period of time, and then expose the resist film to a developer. This is achieved by a method for forming the resist butter 7, which is characterized by a development process.

(f) Examples of the invention Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 2 is a cross-sectional view for sequentially explaining the main steps of an embodiment in which the method of the present invention is applied to a resist pattern for forming a bubble domain transfer loop pattern formed by etching the magnetic film of a magnetic baffle memory element. be.

In FIG. 2(a), a positive resist film 12 having a thickness of about 700 OA is deposited on the surface of a soft magnetic film 11 made of permalloy or the like deposited on the surface of the substrate by means of a spin code.

Next, the surface of the resist film 12 is exposed to a developer (alkaline aqueous solution) for 30 seconds to 90 seconds using an immersion or dipping method. As a result, as shown in FIG. 2(b), the resist film 1
An altered layer 13, which is less sensitive to light than the resist film, is formed on the entire surface of the resist film.Next, when normal exposure and image processing are performed, the resultant layer 13 shown in Fig. 2 (c) is formed.
As shown in FIG. 1, a resist pattern 14 has a remaining portion 13' of the altered layer 13 mounted on the remaining portion 12' of the resist film 12.
is formed. However, the cross-sectional shape of the resist pattern 14 is shown using a scanning electron microscope.
When this shape is compared with the conventional pattern 2 shown in FIG. 1, the edges 14' are formed to be angular.

Therefore, the magnetic film 1 to which the resist pattern 14 is not attached
When the exposed surface layer of No. 1 is removed by ion milling means,
Although the surface layer of the resist pattern 140 can be removed slightly, the angular edge 14' makes it more resistant than the resist pattern 2, making it possible to form an etching pattern with a width of 0.8 μm.0 (,9) Invention As explained in detail, the resist pattern formed by the method of the present invention has superior rigidity to the cyanoching process compared to that formed by the conventional method, so it is possible to miniaturize the etching pattern, and it is possible to improve the structure of semiconductor devices and magnetic bubbles. The effects of increasing the areal density and performance of these materials are extremely large.

[Brief explanation of the drawing]

FIG. 1 is a diagram for explaining the cross-sectional shape of a resist pattern 7 formed by a conventional method, and FIG. 12: It is a diagram for explanation. In the figure, 1 is Ueno (substrate), 2゜14
1 is a resist pattern, 2' and 14' are edge parts, 11 is a magnetic film deposited on the substrate, 12 is a resist film, 12' is a remaining part of the resist film after development, 13 is a deteriorated layer of the resist film, 13' indicates the remaining portion of the deteriorated layer due to development of the resist film.

Claims (1)

[Claims] 1. A method for forming a resist pattern, which comprises depositing a resist film on the surface of a resist pattern forming substrate, exposing the surface of the resist film to a developer for an appropriate period of time, and then performing exposure and development treatment.