Dry etching method

Abstract

The object of the present invention is to provide a dry etching method by which generation of a notch in an insulating layer can be suppressed and highly-accurate microfabrication can be realized. In a dry etching method according to the present invention, a substrate in which a semiconductor layer is formed on an insulating layer formed of a silicon oxide is prepared, a through-hole is formed in the semiconductor layer, and a resin film is formed on side walls of the through-hole and a recessed portion while forming the recessed portion in the insulating layer by etching an area in which the insulating layer is exposed via the through-hole. By forming the resin film on the side wall of the recessed portion, the side wall of the recessed portion is protected from collision of ions in plasma and generation of a notch in the recessed-portion side wall is suppressed. Furthermore, by forming the resin film on the side wall of the through-hole, the side wall of the through-hole is protected from the collision of ions in plasma and a hole shape of the through-hole is prevented from fluctuating.

Dependencies are inferred from the claim text.