Coating alumina on particles to suppress the differential reaction of Y and La at the interface for high-quality etching-resistant YAG coatings

The inner walls of semiconductor processing chambers are susceptible to corrosion and failure under prolonged exposure to harsh environments. Applying protective ceramic coatings can effectively suppress plasma-induced erosion. This work focuses on high-hardness Y 3 Al 5 O 12 (YAG) ceramics. By introducing La–O bonds, the interfacial strength and corrosion resistance of the coatings are enhanced. A low‑temperature co‑precipitation method combined with liquid‑phase coating was employed to fabricate composite powders of (Y 0.7 La 0.3 ) 2 O 3 @Al 2 O 3 (YLAO) and (Y 0.7 La 0.3 ) 2 O 2 F 2 @Al 2 O 3 (YLAFO) for YAG ceramic coatings, effectively suppressing the differential interfacial reactions between Y and La. The YLAFO coatings exhibit a dense microstructure with uniform elemental distribution. Under NF 3 /O 2 /Ar mixed‑plasma etching conditions, the coating shows an etching rate of only 2.81 nm/min, representing an approximately 88% improvement in erosion resistance compared to Y 2 O 3 ‑derived (YO) YAG coatings. This work demonstrates that coating performance can be enhanced through compositional design and process control, providing a feasible solution for protecting semiconductor etching components.