Method of forming fine patterns of semiconductor device by using double patterning process which uses acid diffusion

A method of forming fine patterns of a semiconductor device, the method comprising:

• forming a plurality of first mask patterns on a substrate;
• forming a capping film on exposed surface areas of each of the plurality of first mask patterns, wherein the capping film comprises an acid source comprising one of acid, a first photoacid generator having a chromophore group, and a thermoacid generator;
• forming a second mask layer on the capping films, wherein the second mask layer comprises polymer having an acid-labile group and comprises neither acid nor potential acid;
• forming a plurality of acid diffused regions within the second mask layer by diffusing acid obtained from the acid source from the capping films into the second mask layer;
• and
• forming a plurality of second mask patterns corresponding to residual parts of the second mask layer which remain after removing the acid diffused regions of the second mask layer.

A method of forming fine patterns of a semiconductor device, the method comprising:

• forming a plurality of first mask patterns on a substrate;
• forming a capping film on exposed surface areas of each of the plurality of first mask patterns, wherein the capping film comprises an acid source comprising one of acid and a thermoacid generator;
• forming a second mask layer on the capping films, wherein the second mask layer comprises a polymer having an acid-labile group and a first photoacid generator having a chromophore group;
• forming a plurality of acid diffused regions within the second mask layer by diffusing acid obtained from the acid source from the capping films into the second mask layer;
• and
• forming a plurality of second mask patterns corresponding to residual parts of the second mask layer which remain after removing the acid diffused regions of the second mask layer.