Fast homoepitaxial growth of (100) β-Ga2O3 thin films via MOVPE

A high growth rate process above 1 mu m/h was achieved for Si-doped (100) beta-Ga2O3 homoepitaxial films grown via metalorganic vapor phase epitaxy (MOVPE) while maintaining high crystalline perfection up to a film thickness of 3 mu m. The main growth parameters were investigated to increase the growth rate and maintain the step-flow growth mode, wherein the enhanced diffusion channel due to the formation of a Ga adlayer was proposed to be the possible growth mechanism. Si doping allowed precise control of the n-type conductivity of the films with electron concentrations ranging from 1.5 x 10(17) to 1.5 x 10(19) cm(-3) and corresponding mobilities from 144 to 21 cm(2) V-1 s(-1), as revealed by Hall effect measurements at room temperature. Secondary ion mass spectrometry confirmed homogeneous Si doping through the film and a one-to-one correlation between the Si concentration and the electron concentration. Low defect density in the films was determined by x-ray diffraction measurements. The demonstration of a high growth rate process of beta-Ga2O3 films with mu m level thickness and smooth surface morphology via MOVPE is critical for high power electronics with vertical device architecture.