||In this study, gallium oxide (Ga2O3) was grown on LiAlO2 (LAO) substrate by chemical vapor deposition (CVD). Argon and oxygen are used as carrier gas and reaction gas, respectively. Pure gallium metal is used as reaction source. The growth pressure is controlled at 30 torr. The growth temperature is at 750oC~950oC respectively. After the reaction of Ga2O3 grown, we used scanning electron microscope, x-ray diffractometer, transmission electron microscope, cathode- luminescence, Raman and transmissionphoto spectroscopy, to analyze the characteristics of Ga2O3, such as crystal structure, surface morphology, growth mechanism, optical properties and energy band gap.|
There are four parts in this experiment: First, the relative location between Gallium source and substrate was investigated in growth time 30 minutes. Second, the experiment parameter was under the condition of the first part, but the growth time was added to 90 minutes. Third, the changed parameter value of this part was the temperature of substrate. The last, the extra oxygen was added to observe the growth situation.
There are two different phase of Ga2O3 grown on LAO. The crystal orientation relationship is (2 ̅01)β-Ga2O3 || (111)γ-Ga2O3 and (111)γ-Ga2O3 || (100)LAO. Although γ-Ga2O3 is metastable phase, but it stably exist at the interlayer. The growth of β-Ga2O3 is anisotropy, (2 ̅01)β-Ga2O3 is parallel to substrate with three different direction variants. The analytic results of cathodoluminescence showed the luminescence property of ultraviolet emission, and showed the band gap of 4.87 eV.