Plasma resistance of Y₂O₃ nanofilms on quartz with different interlayer deposited by EB-PVD

Abstract

The Y₂O₃ films were deposited on quartz plates using an electron beam (EB) evaporation method with different interlayer. The two types of interlayer, which were compositionally graded and alternated stacks of Y₂O₃ and SiO₂ layer, were applied with the intent to prevent flaking of the coating due to a thermal mismatch between the Y₂O₃ film and quartz substrate. The field emission scanning electron microscopy (FESEM) analysis indicated that the Y₂O₃ film with interlayer which consisting of alternated stacks of Y₂O₃ and SiO₂ layer, shows more structural stability, no crack propagation or flaking of the top layer, than other film samples. The plasma resistance of the Y₂O₃ films was analyzed by a plasma etching test using inductively coupled plasma (ICP) conditions with a gas mixture of CF₄/O₂. The etching resistance of the Y₂O₃ films was evaluated by measurement of etching depth. The etching depths of Y₂O₃ films with interlayer were shown as 20 times lower than quartz plate.