Guangxi Key Laboratory of Precision Navigation and Application, Guilin University of Electronic Technology, China

Biography: Fabi Zhang is a Professor of the Guilin University of Electronic Technology. He received the B.S. and M.S. degrees from Harbin institute of technology, Harbin, China, and the Ph.D. degree from Saga University, Saga, Japan, in 2016. He has been selected as the candidates of “Hundred Talents Program for overseas high-level talents “as well as the " Thousands of Key Teachers Training Program" of Guangxi Province, China. His research interests are in wide bandgap semiconductor materials and devices. He has published over 50 referred journal articles.

Speech Title: High pressure influences on properties of Ga₂O₃ based films

Abstract: Oxide semi-conductive novel thin-films of homo- and hetero-structures are technologically attractive for future devices because of their exciting fundamental intrinsic and extrinsic optical, electrical, magneto optical, and piezoelectric properties. They have potential applications such as power device application, piezoelectric sensors, thin film transistors and ultraviolet detectors. Such materials are recognized as being suitable for extreme environment applications such as high temperatures, intense radiation and corrosive environments. And they can be deposited using conventional process method such as sputting, pulsed laser deposition (PLD), metal-organic chemical vapor deposition (MOCVD) and molecular beam epitaxy (MBE) etc. Of the oxide semiconductor, Ga₂O₃ is a potential candidate due to its direct and wide band gap and physical and chemical stabilities. The availability of high quality β-Ga₂O₃ bulk substrates and β-Ga₂O₃ thin films through techniques such as sputtering, chemical vapor deposition, spray pyrolysis, sol-gel method, thermal evaporation, molecular beam epitaxy, and PLD 1,2 has positioned Ga₂O₃ as a strong candidate for next-generation devices.

It is known that oxygen pressure has great influences on the structural and electronical properties of oxide films preparation by PLD. However, the reported oxygen ambient pressure influences by PLD mainly focused on the sub-oxides Ga₂Ox (2.1<x<3) films which were formed at very low oxygen pressure. The oxygen influence on properties of β-Ga₂O₃ crystalline films has seldom been reported. Here, we report the high temperature influences on structure and optical properties of Ga₂O₃ and (GaIn)₂O₃ films. This would be helpful for understanding the high-pressure growth mechanism which has seldom been reported in the process of PLD.

Keywords: pressure; structure; Ga₂O₃; PLD

REFERENCES: [1] F. Zhang, et al., Structural and optical properties of Ga2O3 films on sapphire substrates by pulsed laser deposition, Journal of Crystal Growth, Vol.387, pp 96-100 (2014).
[2] F. Zhang, et al., Wide bandgap engineering of (AlGa)2O3 films, Applied Physics Letters, Vol. 105, pp 162107 (2014).