Journal of Crystal Growth, Vol.424, 77-79, 2015
Oxygen-radical-assisted pulsed-laser deposition of beta-Ga2O3 and beta-(AlxGa1-x)(2)O-3 films
We report on impacts of oxygen radical (O*) atmosphere for pulsed laser deposition (PLD) of beta-Ga2O3 and beta-(AlxGa1-x)(2)O-3 films on (010) beta-Ga2O3 substrate in comparison with conventional PLD in O-2 atmosphere. Severe sublimation of Ga species arising from insufficient oxidation in the O-2 atmosphere resulted in substantial decrease in growth rate of the homoepitaxial films and condensation of Al content in the (AlxGa1-x)(2)O-3 films. In the case of Q* assisted PLD, it was found that the growth rate of homoepitaxial films greatly recovered, and the Al content remained nearly identical to that in the target. Moreover, the use of O* allowed to reduce surface roughness of homoepitaxial films. These results indicate that Q*-assisted PLO is a powerful tool for fabricating beta-Ga2O3-based heterostructures. (C) 2015 Elsevier B.V. All rights reserved.
Keywords:Pulsed laser deposition;Ga2O3;Alloys;Semiconductor gallium compounds;Semiconductor aluminum compounds