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تسجيل مستخدم جديدN-type doping of LPCVD-grown b{eta}-Ga2O3 thin films using solid-source germanium
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We report on the growth and characterization of Ge-doped b{eta}-Ga2O3 thin films using a solid germanium source. b{eta}-Ga2O3 thin films were grown using a low-pressure chemical vapor deposition (LPCVD) reactor with either an oxygen or gallium delivery tube. Films were grown on 6 degree offcut sapphire and (010) b{eta}-Ga2O3 substrates with growth rates between 0.5 - 22 {mu}m/hr. By controlling the germanium vapor pressure, a wide range of Hall carrier concentrations between 10^17 - 10^19 cm-3 were achieved. Low-temperature Hall data revealed a difference in donor incorporation depending on the reactor configuration. At low growth rates, germanium occupied a single donor energy level between 8 - 10 meV. At higher growth rates, germanium doping predominantly results in a deeper donor energy level at 85 meV. This work shows the effect of reactor design and growth regime on the kinetics of impurity incorporation. Studying donor incorporation in b{eta}-Ga2O3 is important for the design of high-power electronic devices.
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