JPS6095436A - Manufacture of photomask - Google Patents

Abstract

PURPOSE:To obtain high production speed by sputtering metallic Cr on a glass base in an atm. of Ar and Xe mixture to form a Cr film, and subjecting it to dry etching through a patterned photoresist to form a photomask. CONSTITUTION:A metallic Cr film 11 is formed on a glass base 10 by sputtering metallic Cr. This film 11 is coated with a photoresist 12 and after patterning the resist 12, it is subjected to dry etching to form a photomask. In this process, sputtering of the metallic Cr is carried out in an atm. of an Ar and Xe mixture. The metallic Cr film 11 obtained by such sputtering is enhanced in etching speed, and accordingly, the formation speed of the photomask can be enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a method for manufacturing a photomask used in manufacturing semiconductor devices such as ICs and LSIs.

Conventional technology and problems Conventionally, photolithography technology is used to create semiconductor devices for ICs and LSIs, but photolithography technology is also used to create the photomasks used in their creation. .

The process of creating this photomask is to first form a multimetallic chromium film on one side of a glass substrate for a photomask by sputtering, then apply photoresist on top of it, expose it to light using a reticle, develop it, and then selectively etch the chromium film. This creates a pattern.

In this case, the formation of the metal chromium film is performed as shown in FIG. In the figure, 1 is a metal chamber, 2 is a substrate holder having a large number of windows 3, 4 is a beam, and 5 is a slit. and holder 2
A glass substrate for a photomask is placed on the window 3 of the chamber 1, the inside of the chamber 1 is evacuated, argon gas is introduced, and a voltage is applied between the chamber 1 and the target 4 to cause a discharge, and the chrome of the target 4 is struck. It is then taken out and attached to a glass substrate. Dry etching for etching chromium is performed by plasma etching in a mixed gas atmosphere of carbon tetrachloride and oxygen, and the etching rate of the chromium film formed as described above is about 300 A/min. For this reason, there is a need to develop a manufacturing method that can achieve a faster production rate.

OBJECTS OF THE INVENTION In view of the above-mentioned conventional requirements, it is an object of the present invention to provide a method for manufacturing a photomask that can manufacture photomasks at a high production rate.

According to the present invention, metallic chromium is sputtered onto a glass substrate to form a metallic chromium film, and after coating and patterning a photoresist on the metallic chromium film,
This is achieved by providing a method for manufacturing a photomask in which a metallic chromium film is dry-etched, characterized in that the sputtering of the metallic chromium is carried out in a mixed gas atmosphere of argon and xenon.

Examples of the invention Embodiments of the present invention will be described in detail below with reference to the drawings.

The method of the present invention is performed in the Sufu9 tuttering device shown in FIG.
When forming a metallic chromium film on a glass substrate, sputtering is performed using a mixed gas of argon and xenon as the atmosphere, and then a photoresist is deposited on the metallic chromium film 11 formed on the glass substrate 10 as shown in FIG. After coating and patterning 12, dry etching is performed in an atmosphere of carbon tetrachloride and oxygen.

As an actual example, chromium sputtering was carried out under the conditions shown in Table 1, and dry etching of the metallic chromium film was carried out under the conditions shown in Table 2.

Table 1 Table 2 As a result, when chromium was shot in a mixed gas atmosphere of argon and nitrogen using the conventional method and dry etched under the conditions shown in Table 2, the etching rate was 300 A/min. The dry etching rate of sputtered chromium in a mixed gas atmosphere of argon and xenon according to the method of the present invention is 500 to 600 A/min, which is 1.
It was possible to obtain an etching rate 5 to 2 times faster.

Effects of the Invention As explained in detail above, the photomask manufacturing method according to the present invention uses a mixed gas of argon and xenon during chromium sputtering to obtain a metallic chromium film with a high dry etching rate, which improves photomask production. This has a great effect in that speed can be improved.

[Brief explanation of drawings]

FIG. 1 is a diagram for explaining the conventional method of manufacturing a photomask and the method of manufacturing a photomask according to the present invention, and FIG. 2 is a sectional view of the photomask before dry etching the metal chromium film. In the drawings, 1 is a metal chamber, 2 is a substrate holder, 4 is a chrome target, 10 is a glass substrate, 11 is a metal chromium film, and 12 is a photoresist. Patent applicant Fujitsu Limited Patent agent Akira Aoki Patent attorney Kazuyuki Nishidate Patent attorney Yukio Uchida Akira Yamaguchi

Claims (1)

[Claims] 1. A photomask manufacturing method in which a metal chromium film is formed by sputtering metal chromium on a glass substrate, a photoresist is applied and patterned on the metal chromium film, and then the metal chromium film is dry-etched. The method for manufacturing photomasks is characterized in that the process is carried out in a mixed gas atmosphere of argon and xenon.