METHOD FOR PREPARING ALUMNA COATING FILM HAVING Alpha-TYPE CRYSTAL STRUCTURE AS PRIMARY STRUCTURE

摘要

For forming alumina films on substrates by sputtering of an aluminum metal target in an oxidizing gas-containing atmosphere, a method of producing alpha crystal structure-based alumina films efficiently is provided which comprises, as the early film formation stage, the step of forming films under conditions suited for the formation of alpha crystal structure alumina, for example the step comprising forming alpha crystal structure alumina in the poisoning mode discharge condition only in the early stage of film formation.