Sputtering resistance and damage mechanism of Y2O3-based ceramics etching by Xe plasma

Abstract

To demonstrate the relation between yttrium oxide-based (Y2O3-based) ceramics and plasma etching behavior, Y2O3-based ceramics were prepared by adding different amounts of alumina to the matrix, and the effect of the different amounts of alumina on its plasma etching resistance was investigated. Xe plasma flow generated by Hall Thruster was used for sputtering the surface of the samples to evaluate the plasma etching resistance. XRD, XPS, SEM, and AFM were used to characterize the phase composition and morphologies of as-made composite ceramics before and after Xe plasma etching. The results suggest that the introduction of alumina reduces the etching resistance of Y2O3-based ceramics. When the main phases of the sintered ceramics are Y2O3, Y3Al5O12 (YAG) and Y3Al5O12+Al2O3 (YAGA), the etching rates are 23 nm min−1, 59 nm min−1 and 152 nm min−1, respectively. Xe plasma is found to homogeneously etch the surfaces of the sintered Y2O3 matrix ceramic materials, yet the etching rates on different crystal surfaces are different, regardless of the phase composition of the materials. Overall, the high-density YAG ceramics can maintain both the etching rate per unit time and the surface roughness at a low level, which is a kind of complementary material to replace Y2O3 ceramics.