JPH02224331A - Manufacture of semiconductor device - Google Patents

Abstract

PURPOSE:To enable a fine pattern in high dryetching resistance to be formed by a method wherein a resin film mainly comprising polymer is patterned on an element to be etched and after coating a silica coating film, the silica coating film and the said element are etched away. CONSTITUTION:After forming a silicon oxide film 2 on a silicon substrate 1, a photoresist 4 is patterned according to the normal photolithographic process. Next, a silica coating film 5 is formed by spin-coating process. At this time, a so-called silicified photoresist layer 6 mixed with silica and the photoresist 4 is formed on the surface of the photoresist melted into the solution of silica coating solvent. Through these procedures, an etching mask in high dryetching resistance in submicron can be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method of manufacturing a semiconductor device, and particularly to the formation of an etching mask.

[Prior Art] Conventionally, positive resist photolithography technology has been used to miniaturize patterns of semiconductor devices. These techniques are so common that they do not require any explanation, but one example is shown in Figures 3(a) and (b). In the figure, 1 is a semiconductor substrate, 2 is a silicon oxide film, and 4 is a silicon oxide film. It is a photoresist. In this way, after patterning the photoresist 4, the silicon oxide film 3 is etched.

[Problems to be Solved by the Invention] However, in the conventional techniques described above, in order to form fine patterns, it is necessary to reduce the molecular weight of the base polymer, which requires a reduction in heat resistance and dry resistance. This method has the disadvantage of reduced etching properties, and there is a problem in developing a technique for forming fine patterns with high heat resistance and etching resistance.

The present invention is intended to solve the above-mentioned problems, and its purpose is to provide a technology for realizing the formation of fine patterns with dry etching resistance. .

[Means for Solving the Problems J] The method for manufacturing a semiconductor device of the present invention includes (1) patterning a mask on an object to be etched, and then etching the object to be etched into an arbitrary pattern using the mask; A method for manufacturing an apparatus includes: a) patterning a resin film mainly made of polymer on an object to be etched; b) then coating a silica coating film.

C) The method is characterized by comprising a step of etching the silica coating film and the object to be etched.

[Function 1] The effect of the present invention is to siliconize the resist surface by bringing the silica coating film into contact with the resist, thereby making it possible to form an etching mask with high dry etching resistance.

〔Example〕

The present invention will be described in detail below based on examples.

FIG. 1 is a process sectional view of the main part of the first embodiment of the present invention.

FIG. 2 is a process sectional view of the main parts of a second embodiment of the present invention.

FIG. 3 is a process sectional view of the main parts of a conventional embodiment.

First, as a first example, as shown in FIG. 1(a),
For example, after forming a silicon oxide film (2) on a silicon substrate (1), photoresist is applied.

Then, as shown in FIG. 1(b), a silica coating film (5) is formed by spin coating. At this time, a so-called siliconized photoresist layer (6) in which silica and photoresist are mixed is formed on the surface of the photoresist dissolved in the solvent of the silica coating solution.

Next, as shown in FIG. 1(C), a silicon oxide film (2) is formed.
Using a reactive ion etching device, for example, CHF5 gas as a hydrogen fluoride gas is etched at 10 Pa at IW/crn.
Etching with a power density of At this time, the silica coating film is also etched together. At this time, the etching rate of the siliconized photoresist on the photoresist surface is 11% compared to that of conventional photoresist.
A vertical shape with almost no difference in zero dimension conversion was obtained, which was 317 people/min for 15.3.

Next, as a second embodiment, as shown in FIG. 2(a), for example, a silicon oxide film (2) is formed on a silicon substrate (1).
After forming the aluminum silicon alloy (3), a photoresist (4) is applied.

Then, as shown in FIG. 2(b), a silica coating film (5) is formed by spin coating. At this time, on the surface of the photoresist dissolved in the solvent of the silica coating solution, a so-called siliconized photoresist layer (6) in which silica and photoresist are mixed is formed, as in the first embodiment.

Then, as shown in Figure 2 (C), HF+NH4F+Cl
-1m Remove the silica coating film with C0OH solution.

Next, as shown in FIG. 2(d), the aluminum silicon alloy is etched using a reactive ion etching device.

For example, as a chlorine gas, Cj! a, BCl2. Etching gas is performed at a power density of 1.5 W/crn'' at 7 Pa. At this time, the etching rate of the siliconized photoresist on the photoresist surface is 425 people/crn, which is 1/4.7 of that of conventional photoresist. A vertical shape with almost no 0 dimension conversion difference, which was the minimum, was obtained.

By siliconizing the surface of the photoresist as described above, it was possible to form a mask with high heat resistance and dry etching resistance on the photoresist for miniaturization.

The manufacturing method introduced in the examples is of course not limited to this, and it does not depend on the material of the underlying object to be etched, nor is the etching condition limited to this, but various methods may be used. Can be done.

[Effects of the Invention] According to the above structure of the present invention, since the surface of the resist is siliconized by contacting the resist with a silica coating film, an etching mask with high dry etching resistance can be formed.

In conventional dry etching of oxide films, the resist etching rate is approximately five times or more, and in the case of aluminum silicon alloys, it is approximately four times or more, making it possible to form etching masks with high submicron dry etching resistance. did it.

[Brief explanation of the drawing]

FIGS. 1(a) to 1(c) are process cross-sectional views showing the first embodiment of the method for manufacturing a semiconductor device of the present invention in order of process. FIGS. 2(a) to 2(d) are process cross-sectional views showing the second embodiment of the method for manufacturing a semiconductor device of the present invention in order of process. FIGS. 3(a) and 3(b) are cross-sectional views showing an example of a conventional method for manufacturing a semiconductor device.・Semiconductor substrate ・Silicon oxide film ・Aluminum silicon alloy photoresist ・Silica coating film ・Siliconized resist Applicant: Seiko Epson Corporation

Claims (1)

[Claims] ν (1) A method for manufacturing a semiconductor device in which a mask is patterned on an object to be etched, and then the object to be etched is etched into an arbitrary pattern using the mask, comprising: A semiconductor device comprising the steps of patterning a resin film made of a polymer, b) coating a silica coating, and c) etching the silica coating and an object to be etched. manufacturing method.