摘要 |
On a surface of a semiconductor wafer W, a SiCN film, a SiCOH film, a TEOS film, an antireflection film, and a resist film (ArF resist) as a mask are formed in turn. A via hole is formed by plasma etching the SiCOH film with a predetermined etching gas comprising a mixed gas, for example, CF<SUB>4</SUB>/CH<SUB>2</SUB>F<SUB>2</SUB>/N<SUB>2</SUB>/O<SUB>2 </SUB>mixed gas (not containing a rare gas such as an Ar gas). Thereby, the selection ratio between a low dielectric constant insulation film comprising a carbon containing silicon oxide and the resist can be improved. And at the same time, even when the hole has a minute diameter and a high aspect ratio, an inner wall surface of the hole can be formed in a satisfactory state.
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