FLANGE FOR PLASMA CAVITY, PLASMA CAVITY, AND PLASMA CVD APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a flange for a plasma cavity capable of effectively introducing phosphorus (P) in a material gas into a diamond film, a plasma cavity, and a plasma CVD apparatus.SOLUTION: The flange for a plasma cavity of a substantially disc shape whose outer peripheral side face part is of a micro wave reflection shape is provided with a gas exhaust region of a ring shape in a plan view so as to surround a substrate arrangement region. In the gas exhaust region, 6 or more holes of a circular shape in a plan view are provided. Diameters of the holes are equal to or less than 6 mm, and are provided in point symmetry to a substrate center point. Intervals between the centers of the neighboring holes are equal to or larger than 5.5 mm.