| 摘要 |
The present invention is a plasma etching method in which a process gas is used under plasma conditions, and is characterized in that at least one type of hydrofluoroether selected from the hydrofluoroethers represented by formula (I) is used as the process gas. In formula (I), R represents a hydrogen atom or a fluoroalkyl group represented by CnF2n+1. m and n are integers that satisfy 1 ≤ m ≤ 3 and 3 ≤ (m + n) ≤ 4. This plasma etching method enables high etching selectivity with silicon nitride, silicon, and organic materials to be achieved while obtaining sufficiently high etching speed even if oxygen or hydrogen are not used when etching silicon oxides. |
