Method of making gate wiring layer over semiconductor substrate

Abstract

Disclosed is a method of making a gate wiring layer, in which a carbon-based layer is patterned by dry etching using a gas that does not etch a gate insulating layer so as to form a gate wiring layer without deteriorating the gate insulating layer and without etching the semiconductor substrate. In forming a gate insulating layer and a gate wiring layer on a semiconductor substrate, a carbon-based layer is formed on a semiconductor substrate, followed by forming a predetermined mask on the layer for patterning the layer. The carbon-based layer is etched by dry etching using an oxygen gas, a carbon monoxide gas or a mixed gas containing an oxygen gas, a nitrogen gas, a carbon monoxide gas and an argon gas and without containing a halogen gas. The etching is selectively stopped by the insulating layer. The insulating layer of, for example, SiO is etched by dry etching using a halogen-containing gas, but is scarcely etched by dry etching using an oxygen-containing gas that does not contain a halogen gas.