Investigation of β-Ga2O3 films and β-Ga2O3/GaN heterostructures grown by metal organic chemical vapor deposition

• Published in: Science China. Physics, mechanics & astronomy Vol. 63; no. 11; p. 117311
• Main Authors: Zhang, YaChao, Li, YiFan, Wang, ZhiZhe, Guo, Rui, Xu, ShengRui, Liu, ChuanYang, Zhao, ShengLei, Zhang, JinCheng, Hao, Yue
• Format: Journal Article
• Language: English
• Published: Beijing Science China Press 01.11.2020; Springer Nature B.V
• Subjects: Astronomy; Chemical vapor deposition; Classical and Continuum Physics; Conduction bands; Energy bands; Gallium oxides; Heterostructures; Homogeneity; Investigations; Metalorganic chemical vapor deposition; Observations and Techniques; Organic chemicals; Organic chemistry; Photoelectrons; Physics; Physics and Astronomy; Sapphire; Substrates; X ray photoelectron spectroscopy; 68.47.Gh; 73.40.Kp; GaN substrate; band structure; β-Ga; interface; MOCVD; O; 81.05.Ea
• ISSN: 1674-7348; 1869-1927
• DOI: 10.1007/s11433-019-1546-3

In this work, (-2 0 1) β-Ga 2 O 3 films are grown on GaN substrate by metal organic chemical vapor deposition (MOCVD). It is revealed that the β-Ga 2 O 3 film grown on GaN possesses superior crystal quality, material homogeneity and surface morphology than the results of common heteroepitaxial β-Ga 2 O 3 film based on sapphire substrate. Further, the relevance between the crystal quality of epitaxial β-Ga 2 O 3 film and the β-Ga 2 O 3 /GaN interface behavior is investigated. Transmission electron microscopy result indicates that the interface atom refactoring phenomenon is beneficial to relieve the mismatch strain and improve the crystal quality of subsequent β-Ga 2 O 3 film. Moreover, the energy band structure of β-Ga 2 O 3 /GaN heterostructure grown by MOCVD is investigated by X-ray photoelectron spectroscopy and a large conduction band offset of 0.89 eV is obtained. The results in this work not only convincingly demonstrate the advantages of β-Ga 2 O 3 films grown on GaN substrate, but also show the great application potential of MOCVD β-Ga 2 O 3 /GaN heterostructures in microelectronic applications.