METHOD OF SELECTIVE ETCH BY USING HARD MASK AND METHOD OF FORMING ISOLATION OF MEMORY DEVICE BY USING THE SAME

摘要

A selective etch method using a hard mask is provided to increase etch selectivity by introducing a hard mask containing a carbon nanotube. Carbon nanotubes(161) are mixed in polymer. The carbon nanotube-polymer mixture is deposited on an etch target layer to form a carbon nanotube-polymer mixture layer. The carbon nanotube-polymer mixture layer is patterned to form a hard mask(169) selectively exposing a partial region of the etch target layer. A region of the etch target layer exposed by the hard mask is selectively etched. The polymer can include a photoresist material. The process for forming the hard mask can include a process for performing an exposure and development process on a mixture layer of the photoresist and the carbon nanotube.