Patent ID: 7879179

Claim:
A plasma processing apparatus, which processes a semiconductor substrate or a substrate of a liquid crystal display, the plasma processing apparatus comprising: a processing vessel configured to accommodate a substrate to be processed, the processing vessel including a lower chamber and an upper chamber disposed above the lower chamber such that the lower chamber forms an accommodation space for accommodating the substrate and the upper chamber forms a plasma generation space for generating plasma, the upper chamber including a wall portion made of a material selected from the group consisting of Al 2 O 3 , AlN, and SiO 2 ; a support member configured to support the substrate inside the lower chamber; a gas supply mechanism configured to supply a process gas into the processing vessel; an exhaust mechanism configured to exhaust gas from inside the processing vessel; and a plasma generation mechanism configured to generate plasma from the process gas inside the upper chamber, the plasma generation mechanism including an antenna disposed outside the wall portion of the upper chamber and configured to be supplied with a high frequency power; and a protection film covering an inner surface of the wall portion of the upper chamber to be exposed to the plasma, the protection film being configured to protect the wall portion from the plasma, wherein the protection film is a thermal sprayed film of a compound of Al 2 O 3 and Y 2 O 3 with a weight ratio of Al 2 O 3 to Y 2 O 3 being 0.5 to 4, and is a surface-polished film having a thickness of larger than 50 μm, a breakdown strength of 4 KV or higher, and a plasma resistance such that an amount of etching of the protection film by plasma of CF 4 , Ar, and O 2 is smaller than an amount of etching of alumina by the plasma.