Patent ID: 8936948
Filing Date: 2015-01-20
Classification: H01L

Abstract:
1. A method of fabricating a semiconductor device, comprising: sequentially stacking a hard mask film comprising a material in which the pattern precision is degraded by oxidation, a protective film, a first mask film, a first anti-reflective film and a first photoresist film on a semiconductor substrate; processing the first photoresist film into a line pattern extending in a first direction; etching the first anti-reflective film using the first photoresist film of the line pattern as a mask; transferring the line pattern by etching the first mask film using the first anti-reflective film as a mask; removing the first anti-reflective film that resides on the first mask film to which the line pattern is transferred; sequentially stacking a second anti-reflective film, which is made of an organic film, and a second photoresist film on the first mask film, which is exposed after the first anti-reflective film is removed, and on the protective film; processing the second photoresist film into a pattern having an opening, which extends in a second direction across the first direction; partially removing the second anti-reflective film by etching using the patterned second photoresist film as a mask, thereby exposing a surface of the first mask film to which the line pattern is transferred and leaving the second anti-reflective film on the protective film; etching the first mask film using the second anti-reflective film as a mask, thereby forming a first mask pattern separated in the second direction; removing the second anti-reflective film residing on the first mask pattern and the protective film by ashing; etching the protective film using the first mask pattern as a mask; etching the hard mask film to transfer the first mask pattern using the first mask pattern of the first mask film and the protective film as a mask; and etching the substrate to form a device-isolation trench using the hard mask film to which the first mask pattern is transferred and removing the first mask film and the protective film residing on the hard mask film simultaneously.