Effect of Sputtering Power on Structure and Plasma Resistance of Yttrium Oxide Coatings for Semiconductor Etching

Semiconductor devices often suffer from equipment degradation and contamination risks from high‐energy plasma exposure. To address this issue, this work developed yttrium (Y) oxide coatings via reactive magnetron sputtering from an yttrium target in an Ar/O 2 atmosphere, with sputtering power systematically varied to investigate its impact on coating properties. Characterization techniques including FESEM/EDS, GIXRD, XPS, nanoindentation, and reactive ion etching were employed to evaluate morphology, composition, crystal phase, mechanical properties, and plasma etching behavior. The results revealed a power‐dependent evolution in coatings: at 200 W, coatings formed in poisoning mode, while increasing the power to 400 W triggered a transition to metallic mode, yielding dense, single cubic phase Y‐oxide with uniform morphology and high deposition rates. Further power escalation to 1000 W induced oxygen deficiency, transforming the coatings into nonstoichiometric Y‐oxide with mixed metallic and cubic phases. Notably, the 400 W coating demonstrated the highest hardness and lowest plasma etching rate. Post‐CF 4 /O 2 etching analysis showed that the 400 W coating converted to an oxyfluoride (YO x F y ) surface layer, whereas 1000 W coatings formed YF 3 ‐like surfaces. The reasons for the enhanced plasma resistance of the 400 W coating, namely, its stoichiometric stability and dense microstructure, are discussed in detail.