Manufacture of semiconductor device

Abstract

Abstract PURPOSE:To suppress the contamination and the increase in foreign materials of an etching apparatus, when an aluminum film undergoes anisotropic etching, by using double-layer masks comprising a plasma oxide film and a resist film as masks. CONSTITUTION:An Al film 3 and a plasma oxide film 2 are sequentially formed on an SiO2 film 4. Thereafter, resist 1 is formed as a mask material. Then, the plasma oxide film 2 is etched. A plasma oxide film mask 5 is formed in an anisotropic shape at the approximately same size as that of the resist film 1. Then, with the plasma oxide film 5 and the resist 6 as double-layer mask materials, anisotropic etching of the aluminum is performed. Thus, a selecting ratio for the resist is made low in comparison with conventional process conditions. A gas, which is used in the aluminum etching, can be changed into a gas, in which polymerization is hard to perform in plasma. A high selecting ratio can be realized for the selecting ratio for the mask material. An Al wiring 7 is machined without size shift (side etch) for the plasma oxide film mask 5. As a result, the causes of the contamination of an etching apparatus due to deposition gas and the increase in foreign materials can be eliminated.

Inventors

• 👤 Satoshi Ioka

Bibliographic Details