Band alignment of p-type oxide/ε-Ga2O3 heterojunctions investigated by x-ray photoelectron spectroscopy  

作　　者：Chang Rao Zeyuan Fei Weiqu Chen Zimin Chen Xing Lu Gang Wang Xinzhong Wang Jun Liang Yanli Pei 饶畅;费泽元;陈伟驱;陈梓敏;卢星;王钢;王新中;梁军;裴艳丽(School of Electronics and Information Technology,State Key Laboratory of Optoelectronics Materials&Technologies,Sun Yat-Sen University,Guangzhou 510006,China;Department of Electronic Communication and Technology,Shenzhen Institute of Information Technology,Shenzhen 518172,China;School of Advance Materials,Peking University Shenzhen Graduated School,Shenzhen 518055,China)

机构地区：[1]School of Electronics and Information Technology,State Key Laboratory of Optoelectronics Materials&Technologies,Sun Yat-Sen University,Guangzhou 510006,China [2]Department of Electronic Communication and Technology,Shenzhen Institute of Information Technology,Shenzhen 518172,China [3]School of Advance Materials,Peking University Shenzhen Graduated School,Shenzhen 518055,China

出　　处：《Chinese Physics B》2020年第9期476-481,共6页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant No.61774172);the Guangdong Provincial Department of Science and Technology,China(Grant Nos.2019B010132002 and 2016B090918106);the Pengcheng Scholar Funding(2018);Shenzhen Science and Technology Innovation Committee,China(Grant No.KQJSCX20180323174713505).

摘　　要：Theε-Ga2O3 p-n heterojunctions(HJ)have been demonstrated using typical p-type oxide semiconductors(NiO or SnO).Theε-Ga2O3 thin film was heteroepitaxial grown by metal organic chemical vapor deposition(MOCVD)with three-step growth method.The polycrystalline SnO and NiO thin films were deposited on theε-Ga2O3 thin film by electron-beam evaporation and thermal oxidation,respectively.The valence band offsets(VBO)were determined by x-ray photoelectron spectroscopy(XPS)to be 2.17 eV at SnO/ε-Ga2O3 and 1.7 eV at NiO/ε-Ga2O3.Considering the bandgaps determined by ultraviolet-visible spectroscopy,the conduction band offsets(CBO)of 0.11 eV at SnO/ε-Ga2O3 and 0.44 eV at NiO/ε-Ga2O3 were obtained.The type-Ⅱband diagrams have been drawn for both p-n HJs.The results are useful to understand the electronic structures at theε-Ga2O3 p-n HJ interface,and design optoelectronic devices based onε-Ga2O3 with novel functionality and improved performance.

关 键 词：ε-Ga2O3 x-ray photoelectron spectroscopy(XPS) valence band offset band alignment 

分 类 号：TN304[电子电信—物理电子学]