Dry etching of SnO _2 and ZnO films in halogen-based inductively coupled plasmas (Conference Paper)

摘要

High density plasma etching of SnO _2 and ZnO films was performed in chlorine- (Cl _2/Ar and BCl _3/Ar) and fluorine-based (CF _4/Ar and SF _6/Ar) inductively coupled plasmas. The etch process window for fabricating metal oxide nanowires with high aspect ratios including high and controllable etch rates, high etch selectivities to mask material and high anisotropy was established. Maximum etch rates of ～2050 ?/minute (BCl _3/Ar) and ～1950 ?/minute (SF _6/Ar) for ZnO, and ～1950 ?/minute (Cl _2/Ar) and ～2000 ?/minute (SF _6/Ar) for SnO _2 were obtained. Ni was found to provide very high etch selectivities with maximum values of ～67 to SnO _2 and ～17 to ZnO, respectively.