Effect of oxidation on the optical and surface properties of AlGaN

Wang XL (Wang X. L.)
Zhao DG (Zhao D. G.)
Chen J (Chen J.)
Li XY (Li X. Y.)
Gong HM (Gong H. M.)
Yang H (Yang H.)
Wang, XL, Chinese Acad Sci, Inst Semicond, State Key Lab Integrated Optoelect, POB 912, Beijing 100083, Peoples R China. E-mail: WXL@mail.semi.ac.cn

Publication date

January 2006

Abstract

The chemical properties of AlxGa1-xN surfaces exposed to air for different time periods are investigated by atomic force microscopy (AFM), photoluminescence (PL) measurement and X-ray photoelectron spectroscopy (XPS). PL and AFM results show that AlxGa1-xN samples exhibit different surface characteristics for different air-exposure times and Al contents. The XPS spectra of the Al 2p and Ga 2p core levels indicate that the peaks shifted slightly, from an Al-N to an Al-O bond and from a Ga-N to a Ga-O bond. All of these results show that the epilayer surface contains a large amount of Ga and Al oxides. (c) 2006 Elsevier B.V. All rights reserved