Patent ID: 7998663

Claim:
A pattern formation method comprising the steps of: a) forming an underlying layer film on a substrate; b) forming an intermediate layer film on the underlying layer film; c) forming a first resist film on the intermediate layer film and then performing exposure and development to the first resist film through a first photomask having a first pattern, thereby forming a first resist pattern; d) etching the intermediate film using the first resist pattern as a mask, thereby forming a first intermediate layer pattern; e) removing the first resist pattern; f) forming, after the step e), a second resist film on the underlying layer film and the first intermediate layer pattern, and then performing exposure and development to the second resist film through a second photomask having a second pattern, thereby forming a second resist pattern; g) etching the first intermediate layer pattern using the second resist pattern as a mask, thereby forming a second intermediate layer pattern; h) removing the second resist pattern; and i) etching, after the step h), the underlying layer film using the second intermediate layer pattern as a mask, thereby forming an underlying layer pattern including the first and second patterns, wherein the underlying layer film is formed of an organic material having a resistance against oxygen-based plasma, in the step e), the first resist pattern is removed by ashing with oxygen-based plasma, and the underlying layer film is formed of an organic material to which a fluorine-based surfactant is added.