Processing apparatus, coated article and method

摘要

A processing apparatus for use in a corrosive operating environment is provided. The apparatus includes a base substrate for placing a wafer thereon. The base substrate has a coefficient of thermal expansion. At least one electrode is embedded in or disposed on or under the base substrate. The electrode has a coefficient of thermal expansion in a range of from about 0.70 to about 1.25 times that of the base substrate coefficient of thermal expansion (CTE). At least one coating layer is disposed on the base substrate. The coating layer includes a composition capable of forming a calcium aluminate coating. The calcium aluminate coating layer is doped with one of MgO, CaO, CaF₂ and mixtures thereof to control the CTE of the coating layer to match the CTE of the base substrate. The apparatus is exposed to a corrosive operating environment at a temperature range of from about 25 degrees Celsius to about 1500 degrees Celsius. A coated article and associated method are provided.