Heterostructure formation of group-III sesquioxides via cation-exchange reactions with metal chloride gases

Thermodynamic analyses and experimental demonstrations were performed to investigate whether cation-exchange reactions (CERs) with metal chloride gases are a feasible technique for forming heterostructures of group-III sesquioxides. The thermodynamic revealed the possibility formation aluminum oxide (Al2O3) layers on gallium (Ga2O3) or indium (In2O3) substrates via CERs gases, as well Ga2O3 In2O3 in practical temperature range. However, did not occur Al2O3 substrates, suggesting that formed. On basis results analyses, CER was by reaction n-type β-Ga2O3(2̄01) trichloride gas, resulting layers. Under optimal conditions, dense (001)-oriented κ-Al2O3 layer thickness 30 nm formed served an excellent gate metal–oxide–semiconductor devices. relative dielectric constant obtained capacitance–voltage measurements, high value ∼22 several tens kHz band. using open new method