KR960008095B1 - Method of micro patterning using organo arc layer - Google Patents

Abstract

The method includes the steps of; (1) forming organic ARC(antireflected coating layer) layer; (2) forming photoresist film pattern on ARC layer; (3) hardening it by heat treatment; (3) coating insulation layer such as silicon oxide or silicon nitride film by PECVD method; (4) forming insulation layer spacer on the side of photoresist film pattern; (5) dry etching the exposed organic ARC layer from insulation layer spacer and photoresist film pattern.

Description

Micro pattern formation method using organic arc layer

1A and 1B are cross-sectional views showing the steps of forming a fine pattern by the prior art.

2a to 2d are cross-sectional views showing the step of forming a fine pattern by the present invention.

* Explanation of symbols for main parts of the drawings

1: Organic Arc Layer 1A: Organic Arc Layer Pattern

2: photosensitive film 2A: photosensitive film pattern

3A: silicon oxide film spacer 3: silicon oxide film

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of forming a fine pattern using an organic arc layer (ARC: Anti Reflected Coating Layer), which is used as an antireflection film to prevent diffuse reflection of an etched layer when forming a fine pattern of a highly integrated semiconductor device. The present invention relates to a method of forming a fine pattern by forming a silicon oxide spacer on a sidewall of a photoresist pattern after forming the photoresist pattern and then etching the organic arc layer, which is a lower layer.

It is difficult to form a fine pattern smaller than 0.4 μm in the conventional single layer resist process, and a notching phenomenon occurs in which a part of the photoresist pattern is lost due to the topology of the lower layer. There is this.

Therefore, in order to compensate for these disadvantages, a process using a tri-level photoresist process or an organic arc layer has been developed.

However, the three-layer photoresist process has a very complicated process, so that the yield is low, and the process using the organic arc layer has another problem that it is difficult to control the critical dimension and thus the reproducibility of the process is poor.

Referring to FIGS. 1A and 1B to form a pattern by a conventional technique using the organic arc layer, the following is described.

In FIG. 1A, an organic arc layer 1 is formed on an etched layer (not shown) made of an insulating film, a conductive layer, or the like, and a single layer photoresist film 2 having a predetermined thickness is coated on the organic arc layer 1. It is sectional drawing which formed the photosensitive film pattern 2A by the selective exposure and image development process using an exposure mask.

FIG. 1B is a cross-sectional view of the organic arc layer pattern 1A formed by removing the organic arc layer 1 exposed by the dry etching process using the photosensitive film pattern 2A as a mask. Critical Dimension Loss of the layer pattern 1A is generated, resulting in a reduction in process margin, thereby degrading process yield and reliability of device operation.

In addition, since the size of the organic arc layer pattern is the same as the single-layer photoresist film process, it is difficult to form a fine pattern of 0.25 μm or less, which makes it difficult to highly integrate a device to a certain degree.

Therefore, in order to solve the above problems, the present invention forms a photoresist pattern on an organic arc layer, forms a silicon oxide spacer or a silicon nitride spacer on a sidewall of the photoresist pattern, and then exposes the exposed organic arc layer. The purpose of the present invention is to provide a method for forming a fine pattern by forming a fine pattern by dry etching, which is advantageous for high integration of a device and an increase in process margin, thereby improving process yield and reliability of device operation.

Hereinafter, with reference to the accompanying drawings will be described in detail the present invention.

2A to 2D are cross-sectional views showing steps of forming a fine pattern according to the present invention.

Referring to FIG. 2A, an organic arc layer 1 is formed on an etched layer (not shown), for example, an insulating film or a conductive layer, and a single layer photoresist film 2 is formed on the organic arc layer 1. After coating, the photosensitive film pattern 2A is formed by an exposure and development process using an exposure mask.

Referring to FIG. 2B, the photoresist pattern 2A is cured by heat treatment, and then the silicon oxide layer 3 is formed by plasma enhanced chemical vapor deposition (PECVD) on the entire surface of the structure. Deposit. At this time, a silicon nitride film may be deposited instead of the silicon oxide film 3.

Referring to FIG. 2C, a blanket dry etching is performed on the silicon oxide layer 3 without using an etching mask to form silicon oxide layer spacers 3A on the sidewalls of the photoresist layer pattern 2A. .

Referring to FIG. 2D, the organic arc layer 1 exposed by the photosensitive film pattern 2A and the silicon oxide film spacer 3A is dry-etched to form the organic arc layer pattern 1A. In this case, a gap between the organic arc layer pattern 1A and the neighboring organic arc layer pattern 1A, that is, a spacer, may be formed to be 0.25 μm or less.

As described above, according to the present invention, since the single-layer photoresist pattern is cured, an insulating film spacer is formed on the sidewall thereof to form a fine pattern without CD loss. Can improve.

Claims (2)

A method of forming a fine pattern of a semiconductor device, the method comprising: forming an organic arc layer for preventing reflection on an etched layer, forming a photoresist pattern on the organic arc layer, and Heat-treating the pattern, applying an insulating film to the entire surface of the structure, dry-etching the insulating film to form insulating film spacers on the sidewalls of the photosensitive film pattern, and forming the photosensitive film pattern and the insulating film spacer. And dry-etching the organic arc layer exposed by the organic arc layer to form an organic arc layer pattern. The method of forming a fine pattern of a semiconductor device according to claim 1, wherein a silicon nitride film or a silicon oxide film is formed by PECVD.