A Novel Etching Method of Single Crystalline A12o3 Film on Si and Sapphire Using Si Ion Implantation

Abstract

AbstractA new etching method for a single crystalline ΑI2O3(100) film grown on Si(100) by LPCVD and a sapphire wafer is established for the first time using Si ion-implantation and buffered hydrofluoric acid (HF+H2O) chemical etchant to develop many applications of the SOI structure. Line and space patterns of resist were transferred to sharp A12O3 and Si patterns. An etching of 0.1 2/μm-thick-Al2O3 films on Si substrates and sapphire wafers was observed very clearly. The etch rate is lOOÂ/min under implanted conditions of 80kV and 3×1015 cm-2.The implanted ΑI2O3 surfaces are investigated by SIMS and XPS. The change from AI2O3 to Al2O3 SiO2 (aluminosilicate), which can be easily etched HF+H2O, is considered to be a main reason, though bonds broken by implantation are also effective for this etching.