| 摘要 |
In a method for preparing a semiconductor device wherein a first silicon oxide film, a second silicon oxide film and a silicon nitride film are sequentially deposited on a silicon substrate, and both silicon oxide films and the silicon nitride film are patterned, a patterned resist 45 is formed on the silicon nitride film, the silicon nitride film is etched with phosphoric acid the resist serving as a mask, and both silicon oxide films are etched with hydrofluoric acid the resist serving as a mask. |
