Ta-doped epitaxial β-Ga2O3 films deposited on SrTiO3(100) substrates by MOCVD

In this work, we successfully prepared epitaxial beta-Ga2O3 films with different Ta doping concentrations on SrTiO3(100) substrates. XPS measurement indicated that Ta mainly existed in the beta-Ga2O3 lattice as +5 valence state, and the actual doping concentration of the Ta element were determined. XRD and TEM results proved the obtained films were high quality beta-Ga2O3 single crystal films, and the epitaxial relationship between the film and substrate was beta-Ga2O3(100)//SrTiO3(100) with beta-Ga2O3 [001]//SrTiO3 < 011 >. The film with 0.2% Ta doping concentration presented the highest Hall mobility of 11.9 cm(2) V-1 s(-1), whereas the lowest resistivity was 68.8 Omega cm when the Ta concentration is 1.0%. By controlling the Ta concentration, the carrier concentration of the beta-Ga2O3 films could be effectively regulated in the range of 4.15 x 10(15)-1.12 x 10(17) cm(-3). The average transmittances of the films in the visible light region exceeded 95%.

Automated summary

This study successfully prepared epitaxial beta-Ga2O3 films with different Ta doping concentrations, showcasing the ability to control carrier concentration and electrical properties by adjusting Ta concentration. The obtained films exhibited high quality single crystal structure and excellent transmittance in the visible light region.