Pattern forming method using resist underlayer film

Abstract

A pattern forming method which uses a resist underlayer film having resistance to a basic aqueous hydrogen peroxide solution. A pattern forming method including: a first step of applying a resist underlayer film-forming composition containing a solvent and a polymer having a weight average molecular weight of 1,000 to 100,000 and an epoxy group on a semiconductor substrate that may have an inorganic film on the surface, followed by baking, to form a resist underlayer film; a second step of forming a resist pattern on the resist underlayer film; a third step of dry etching the resist underlayer film using the resist pattern as a mask to expose a surface of the inorganic film or the semiconductor substrate; and a fourth step of wet etching the inorganic film or the semiconductor substrate using the dry-etched resist underlayer film as a mask and a basic aqueous hydrogen peroxide solution.

Dependencies are inferred from the claim text.