Patent ID: 8409787

Claim:
A method of manufacturing a semiconductor device, comprising: providing a semiconductor substrate comprising a first region and a second region; forming an object layer on the substrate across the first region and the second region; forming a buffer layer on the object layer; forming a first photoresist pattern on the buffer layer in the first region; etching the buffer layer using the first photoresist pattern as a mask to form a buffer pattern in the first region; forming a spacer on a sidewall of the buffer pattern; forming a mask layer on the object layer across the first region and the second region; forming a second photoresist pattern on the mask layer on the object layer in the second region of the substrate; etching the mask layer on the object layer to expose the spacer and, at the same time, etching the mask layer on the object layer using the second photoresist pattern as a mask to form a second mask pattern formed on the second region; and etching the object layer using the spacer and second mask pattern as a mask.