Sticking layer forming material is provided so as to be exposed to plasma, partially on an anti-deposition plate mounted on the inner wall of a process chamber of an ECR (or microwave) plasma etching system. The sticking layer forming material is refractory metal such as W or refractory metal silicide. After a wafer with a photoresist layer is set on a susceptor, a plasma process (aging process) is performed to form a sticking layer of low hardness on the inner wall of the process chamber, the sticking layer containing WCl.sub.5, WCl.sub.6, etc. and resist components. This sticking layer prevents Si oxyhalide from being scaled off the inner wall of the process chamber during the etching process of Si-containing material after the aging process. The sticking layer forming material may be provided on a wafer and the resist components may be supplied from gas. In this manner, particles are reduced which are otherwise generated more while Si-containing material such as silicide is etched.