MEMBER FOR PLASMA TREATMENT APPARATUS AND PROCESS FOR PRODUCING THE MEMBER

摘要

This invention provides a member for a plasma treatment apparatus, which has excellent anti-sticking properties, is suitable, for example, as a lower electrode in CVD apparatuses, has a stable shape as the lower electrode, and can suppress abnormal discharge during plasma treatment. The member (1) for a plasma treatment apparatus comprises a base material (2) formed of an aluminum alloy having a smoothly machined surface and a treated anodic oxide film (3) provided on the surface of the base material (2) and formed by hydrating an anodic oxide film formed on the surface of the base material (2) to form microcracks therein. The anodic oxide film (3) has a leak current density of more than 0.9 × 10-5 A/cm2 at an applied voltage of 100 V, a film thickness of not less than 3 µm, an arithmetic average surface roughness of less than 1 µm, and a dissolution rate of less than 100 mg/dm2/15 min in a phosphoric and chromic acid immersion test. The flatness of the surface on which the anodic oxide film (3) has been formed is not more than 50 µm.