Surface Oxidation Properties in a Topological Insulator Bi2Te3 Film

• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2013,（10）
• 页码范围: 136-138
• 页数: 3页
• 语种: 英文
• DOI: 10.1088/0256-307X/30/10/106801

摘要

Bi2Te3 films are grown on (111)-oriented GaAs substrates by using the hot wall epitaxy method and the surface oxidation properties in the films are investigated by x-ray photoelectron spectroscopy,Raman spectroscopy,and x-ray diffraction.The results show that the films are c-axis oriented.Two pairs of new peaks in the XPS spectra involved with the binding energies from Bi 4f and Te 3d electrons correspond to Bi-O-Te bonds.Besides the A11g,E2g andA21g vibration modes from Bi2 Te3 films,two new peaks at 93.5cm-1 and 123cm-1 are observed in Raman spectra,which are assigned to α-Bi2O3 and TeO2,respectively.Our results are helpful for analyzing the degradation mechanism of topological surface states in Bi2Te3.