Patent ID: 7615497

Claim:
A method for forming a fine pattern of a semiconductor device, the method comprising: forming a stack layer over a substrate having an underlying layer, the stack layer comprising a first, a second, and a third mask films; forming a photoresist pattern over the third mask film; patterning the third mask film, using the photoresist pattern as an etching mask, to form a first stack pattern comprising a third mask pattern and the photoresist pattern; forming an amorphous carbon layer over the resultant including the first stack pattern; selectively patterning the amorphous carbon layer to form an amorphous carbon pattern formed at sidewalls of the first stack pattern; patterning the second mask film using the amorphous carbon pattern and the photoresist pattern as an etching mask to form a second mask pattern, whereby forming a second stack pattern comprising the amorphous carbon pattern, the first stack pattern and the second mask pattern; forming a spin-on-carbon layer over the second stack pattern; polishing the spin-on-carbon layer to expose the third mask pattern; performing an etching process using the amorphous carbon pattern and the spin-on carbon layer as an etching mask to expose the first mask film, whereby removing the third mask pattern and the exposed second mask pattern; removing the spin-on-carbon layer and the amorphous carbon pattern; and selectively etching the first mask film using the second mask pattern as an etching mask to form a first mask pattern.