Etching method and plasma processing apparatus

The disclosed etching method includes a step (a) of forming a carbon-containing protective film on a surface in a chamber of a plasma processing apparatus. The etching method further includes a step (b) of etching the etching film of the substrate using plasma generated in the chamber from an etching gas containing a hydrogen fluoride gas and a hydrofluorocarbon gas. The substrate includes an etching film which is a silicon-containing film, and a mask which contains carbon and is provided on the etching film. 本发明所公开的蚀刻方法包括在等离子体处理装置的腔室内的表面上形成含有碳的保护膜的工序(a)。蚀刻方法还包括利用在腔室内从包含氟化氢气体及氢氟烃气体的蚀刻气体生成的等离子体对基板的蚀刻膜进行蚀刻的工序(b)。基板包括作为含硅膜的蚀刻膜及含有碳且设置于该蚀刻膜上的掩模。