DSA via hole shrink for advanced node applications
Cheng Chi, Chi Chun Liu, et al.
SPIE Advanced Lithography 2016
The direct self-assembly of cylinder-forming poly(styrene-block-methyl-methacrylate) (PS-b-PMMA) block copolymer is successfully assembled into two orientations, according to the underlying guiding pattern in different areas. Lying-down and perpendicular cylinders are formed, respectively, depending on the design of chemical pattern: sparse line/space pattern or hexagonal dot array. The first chemical pattern composed of prepatterned cross-linked polystyrene (XPS) line/space structure has a period (LS) equal to twice the intercylinder period of the block copolymer (L0). The PS-b-PMMA thin film on the prepared chemical template after thermal annealing forms a lying-down cylinder morphology when the width of the PS strips is less than the width of PS block in the PS-b-PMMA block copolymer. The morphology is only applicable at the discrete thickness of the PS-b-PMMA film. In addition to forming the lying-down cylinders directly on the XPS guiding pattern, the cylinder-forming block copolymer can also be assembled in a perpendicular way on the second guiding pattern (the hexagonal dot array). The block copolymer films are registered into two orientations in a single directed self-assembly process. The features of the assembled patterns are successfully transferred down to the silicon oxide substrate.
Cheng Chi, Chi Chun Liu, et al.
SPIE Advanced Lithography 2016
Ravi Bonam, Chi Chun Liu, et al.
SPIE Advanced Lithography 2017
Chi Chun Liu, Elliott Franke, et al.
SPIE Advanced Lithography 2016
Kafai Lai, Chi Chun Liu, et al.
J. Micro/Nanolithogr. MEMS MOEMS