| 摘要 |
PURPOSE:To prevent the variation of pattern size by using a silicon nitride film in which a hydrogen concentration is under a specified value. CONSTITUTION:A pure nitride film in which a hydrogen concentration is 3atm% or under is used for an inverted pattern in order to improve an etching-resistant property of a nitride film on a temporary pattern boundary. For example, a temporary pattern 2 made of an oxide film 1.0mum thick is formed on a substrate 1. Next, silicon is sputtered in a mixed gas of argon and nitrogen to be covered with a pure nitride film 3 of 0.3mum thickness. A hydrogen concentration of a sputtered nitride film is 0.1atm% or under. A resist film 5 is spread and is dried. The whole surface is etched by the parallel electrode type dry etching using CF4 gas so as to expose the upper part of the temporary pattern 2 from the nitride film 3, after which the residual resist film 5 is removed by an organic solvent. When the temporary pattern made of an oxide film is removed selectively by etching using a buffered hydrofluoric acid, an inverted pattern 6 of the nitride film 3 is left on the substrate 1. |
