A solid solution-comprising ceramic article useful in semiconductor processing, which is resistant to erosion by halogen-containing plasmas. The solid solution-comprising ceramic article is formed from a combination of yttrium oxide, zirconium oxide, and aluminum oxide. In a first embodiment, the solid solution-comprising ceramic article is a solid, sintered body of the solid solution ceramic material. In a second embodiment, the solid solution-comprising article comprises a substrate underlying a solid solution-comprising coating.