Investigation of β-Ga₂O₃ thick films grown on c-plane sapphire via carbothermal reduction

Abstract

We investigated the influence of the growth temperature, O2 flow, molar ratio between Ga2O3 powder and graphite powder on the structure and morphology of the films grown on the c-plane sapphire (0001) substrates by a carbothermal reduction method. Experimental results for the heteroepitaxial growth of β-Ga2O3 illustrate that β-Ga2O3 growth by the carbothermal reduction method can be controlled. The optimal result was obtained at a growth temperature of 1050 °C. The fastest growth rate of β-Ga2O3 films was produced when the O2 flow was 20 sccm. To guarantee that β-Ga2O3 films with both high-quality crystal and morphology properties, the ideal molar ratio between graphite powder and Ga2O3 powder should be set at 10 : 1.

High-quality β-(AlxGa1−x)2O3 thin films on sapphire substrates by face-to-face annealing

“…The optical bandgap ( E g ) can be extracted based on the following formula: 30,31 E g = hv = 1240/ λ g where h is the Planck constant, v is the incident photon frequency, and λ g is the wavelength. 32 As depicted in Fig. 3b, the wavelength for the bandgap calculation can be estimated from the energy axis intercept by linearly fitting the absorption edge in the transmittance curve.…”

Preface to Special Issue on Towards High Performance Ga2O3Electronics: Epitaxial Growth and Power Devices (Ⅰ)

“…Oxygen vacancy level variation of differently-oriented α-Ga 2 O 3 thin films has been proposed as the origin for the observed difference in physical properties. X. Wang and co-workers [3] experimentally show a mist-CVD-based rapid epitaxy technique for the fabrication of high-quality α-Ga 2 O 3 films. Large-scale and uniform α-Ga 2 O 3 thin films up to 2-inch were demonstrated to be grown on sapphire substrates.…”