APPARATUS FOR GAS PROCESSING

摘要

An apparatus for gas processing comprises a showerhead (32) placed immediately under a through window (23) and opposed to a wafer W. The opening area per unit area of gas holes (33) in the showerhead is greater in its outer portions than in its central portions. A gas hole control (34) for opening and closing the gas holes (33) is provided under the showerhead (32). As a result, the surface of a substrate such as a wafer can be uniformly processed by using plasma.