Method of forming connection hole

摘要

A method of forming a connection hole (10), which includes the steps of: laminating an etching stopper film (7) made of a SiN based material and an interlayer insulating film (8) made of a SiOx based material on a substrate (1) in this order; forming an organic film pattern (9) on said interlayer insulating film on the basis of a connection hole pattern; dry-etching said interlayer insulating film using said organic film pattern as a mask while keeping a selective ratio to said etching stopper film; and simultaneously removing both a carbon based protective film deposited on an exposed surface of said etching stopper film by said dry etching and said etching stopper film, using an etching reactive system including at least an oxygen based chemical species.