Patent ID: 8263487

Claim:
A method of forming patterns of a semiconductor device, the method comprising: forming an etching target film on a substrate comprising first and second regions; forming a plurality of first carbon (C)-containing film patterns on the etching target film in the first region; forming a buffer layer which covers top and side surfaces of the plurality of first C-containing film patterns and in which a plurality of recesses are formed in a top surface thereof between the first C-containing film patterns; forming a second C-containing film on the buffer layer in the first and second regions so as to fill the plurality of recesses; exposing the buffer layer in the second region by removing the second C-containing film in the second region; exposing the plurality of first C-containing film patterns by removing a portion of the buffer layer in the first and second regions; and forming a plurality of etching target film patterns by etching the etching target film by using the plurality of first C-containing film patterns, and portions of the second C-containing film, which are filled in the plurality of recesses, as an etching mask, wherein the forming of the second C-containing film comprises forming the second C-containing film so as to fill the plurality of recesses and to completely cover the buffer layer in the first and second regions, and wherein the exposing of the buffer layer in the second region by removing the second C-containing film in the second region comprises: forming a trimming mask pattern on the second C-containing film in the first region; etching the second C-containing film in the second region by using the trimming mask pattern as an etching mask; and exposing the second C-containing film in the first region by removing the trimming mask pattern.