TOP PLATE AND PLASMA PROCESSING APPARATUS

摘要

A ceiling plate provided at a ceiling portion of a process chamber that may be evacuated to a vacuum is disclosed. The ceiling plate allows microwaves emitted from a slot of a planar antenna member provided along with the ceiling plate to pass through the ceiling plate into the process chamber, and includes plural protrusion portions arranged along a circle in a surface of the ceiling plate so as to form plural radially disposed virtual convex portions in a place between the concave portions, the surface facing toward an inside of the process chamber. A thickness of places where the concave portions are formed in the ceiling plate and another thickness of other places where the concave portions are not formed in the ceiling plate are determined so that the number of propagation modes of microwaves is different.