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论文类型：期刊论文

发表时间：2016-12-15

发表刊物：APPLIED SURFACE SCIENCE

收录刊物：SCIE、EI、Scopus

卷号：389

页面范围：199-204

ISSN号：0169-4332

关键字：Vanadium oxide; p-GaN; Molecular beam epitaxy; Phase transition

摘要：High quality VO2 films with precisely controlled thickness were grown on p-GaN/sapphire substrates by oxide molecular beam epitaxy (O-MBE). Results indicated that a distinct reversible semiconductor-to metal (SMT) phase transition was observed for all the samples in the temperature dependent electrical resistance measurement, and the influence of VO2 layer thickness on the SMT properties of the as-grown n-VO2/p-GaN based nitride-oxide heterostructure was investigated. Meanwhile, the clear rectifying transport characteristics originated from the n-VO2/p-GaN interface were demonstrated before and after SMT of the VO2 over layer, which were attributed to the p-n junction behavior and Schottky contact character, respectively. Moreover, the X-ray photoelectron spectroscopy (XPS) analyses confirmed the valence state of vanadium (V) in VO2 films was principally composed of V4+ with trace amount of V5+. The design and modulation of the n-VO2/p-GaN based heterostructure devices will benefit significantly from these achievements. (C) 2016 Elsevier B.V. All rights reserved.