Degradation Test for an Anodic Aluminum Oxide Film in Plasma Etching

A reliability assessment was performed to predict the lifetime of an anodic aluminum oxide film coated on equipment used in plasma etching processes. An anodic aluminum-oxide-coated part was exposed to an argon plasma, and its weight loss was monitored. This plasma test was conducted at four different pressure levels (125, 150, 200, and 250 mTorr). The failure distribution data obtained for each pressure level were found to indicate the same failure mechanism. Subsequently, an inverse power model was the best fit model for describing the relationship between the applied pressure and the lifetime of a part. The failure of the anodic aluminum oxide film caused by long-term exposure to plasma is, thus, shown to be closely linked to a decrease in the weight of the film.