Fine processing

Abstract

Abstract PURPOSE:To obtain a method enabling the formation of a pattern of high resolution, by adopting a two-step etching operation wherein first isotropic and subsequently anisotropic etchings are executed, on the occasion when a thin film pattern of the ground is etched by using a planed layer as a mask. CONSTITUTION:By a chemical dry etching method using a mixed gas of CF4 and O2, a silicon oxide film is etched with a resist pattern 3 of the lowermost layer used as a mask. Since this chemical dry etching process is of isotropic etching, etching extends also from the lateral side of the resist pattern of the lowermost layer serving as the mask, an educed substance is removed thereby, and further the upper edge (edge portion) of the silicon oxide film is removed a little by etching to be rounded. Subsequently, the silicon oxide film 2 is etched to the end by a reactive ion etching method using a mixed gas of CF4 and H2, by using the resist pattern of the lowermost layer as a mask in the same way as in the foregoing chemical dry etching process.

Inventors

• 👤 Iwao Tokawa
• 👤 東川　巌

Bibliographic Details