디자인 룰 50나노 이하의 메모리 소자 제조 공정 중 구리 화학기계적 연마 공정에서 유기산화제가 연마율 및 평탄도에 미치는 영향

Abstract

The increase of removal rate and surface uniformity of copper (Cu) film in Cu chemical mechanical planarization (CMP) was investigated by controlling the corrosion behavior of the Cu film. Butylamine (BA), ethanolamine (EA), hexylamine (HA) and tert-butylamine (TBA) were used as organic oxidizers of Cu film. The interaction between organic oxidizers and the surface of the Cu film was determined by potentiostatic measurement using a potentiometer and by X-ray photoelectron spectroscopy (XPS). Organic oxidizers decreased the open circuit potential of Cu film, which resulted in thick oxidation layers. Cu CMP slurry with organic oxidizers showed higher removal rate (267.43%) and low within wafer non-uniformity (WIWNU) (78.61%), which resulted from soft Cu2O layers by organic oxidizers.