Self-assembly patterning using block copolymer for advanced CMOS technology: optimisation of plasma etching process

The best strategy to transfer nanopatterns formed from the self assembly of PS/PMMA bloc copolymers into a silicon substrate is investigated. We show that a hard mask patterning strategy combined with a plasma cure treatment of the PS mask are necessary to reproduce the PS mask pattern into the silicon with a good critical dimension control. In addition, typical silicon etching plasma condition must be revisited to allow the etching of sub-20 nm holes. These results indicate that block copolymer can be readily used as etching masks for advanced CMOS technology.