Patent ID: 7270936

Claim:
A method for forming patterns in a semiconductor device, comprising: forming a first resist layer on a target layer to be etched on a semiconductor substrate; forming a second resist layer by coating the first resist layer with a negative resist composition containing an alkali-soluble hydroxy-substituted base polymer, wherein the base polymer of the negative resist composition is a Novolac resin partially or fully substituted with a hydroxy group, a silicon-containing crosslinker having an epoxy ring, and a photoacid generator; pre-baking the second resist layer; exposing the second resist layer; performing post-exposure baking on the exposed second resist layer; developing the exposed second resist layer to form a second resist layer pattern; etching the first resist layer using the second resist layer pattern as an etching mask to form a first resist layer pattern; and etching the target layer using the first resist layer pattern as an etching mask.