Angle-resolved x-ray photoelectron spectroscopy study of GeOx growth by plasma post-oxidation
Zhao Zhiqian1, Zhang Jing1, †, Wang Xiaolei2, 3, ‡, Wei Shuhua1, Zhao Chao2, 3, Wang Wenwu2, 3
       

(color online) Ge 3d XPS spectra for Al2O3/GeOx/Ge structures with different GeOx thicknesses at a takeoff angle of 90°. The Ge 3d spectra consist of five peaks related to the Ge substrate (Ge0), Ge suboxide (Ge1+, Ge2+, Ge3+), and GeO2 (Ge4+). The spin–orbit splitting of the Ge 3d5/2 and Ge 3d3/2 doublets is 0.585 eV.