Abstract: A method of forming fine pitch hardmask patterns includes forming a hardmask layer on a substrate and forming a plurality of first mask patterns on the hardmask layer. A buffer layer is formed on the plurality of first mask patterns, and has an upper surface defining recesses between adjacent first mask patterns. Second mask patterns are formed within the recesses formed in the upper surface of the buffer layer. The buffer layer is partially removed to expose upper surfaces of the plurality of first mask patterns, and the buffer layer is then partially removed using the first mask patterns and the second mask patterns as an etch mask to expose the hardmask layer between the first mask pattern and the second mask pattern. Using the first mask patterns and the second mask patterns as an etch mask, the hardmask layer is etched to form hardmask patterns.

Abstract: A method of forming fine pitch hardmask patterns includes forming a hardmask layer on a substrate and forming a plurality of first mask patterns on the hardmask layer. A buffer layer is formed on the plurality of first mask patterns, and has an upper surface defining recesses between adjacent first mask patterns. Second mask patterns are formed within the recesses formed in the upper surface of the buffer layer. The buffer layer is partially removed to expose upper surfaces of the plurality of first mask patterns, and the buffer layer is then partially removed using the first mask patterns and the second mask patterns as an etch mask to expose the hardmask layer between the first mask pattern and the second mask pattern. Using the first mask patterns and the second mask patterns as an etch mask, the hardmask layer is etched to form hardmask patterns.