Method for treating surface of aluminum material and plasma treating apparatus

Abstract

An alumite coating film is formed on a surface of an aluminum electrode by anodic oxidation. Pores formed on the alumite coating film are sealed. Thereafter, a silicon nitride film is formed on a surface of the alumite coating film by plasma CVD. In a plasma etching apparatus using the aluminum electrode on which the alumite coating film and the silicon nitride film are sequentially layered, HBr/HCl gas is used as process gas to perform plasma etching of a wafer. An active radical generated from HBr/HCl etches the wafer and attacks the aluminum electrode. Since the aluminum electrode is protected with the silicon nitride film, an aluminum substrate and the alumite coating film are prevented from being etched. Therefore, impurity materials of the aluminum substrate and the alumite coating film are not dispersed into the chamber of the plasma etching apparatus. As a result, the wafer can be prevented from being contaminated by the impurity materials.

Dependencies are inferred from the claim text.