Heteroepitaxial growth of ε-(Al&ITx&ITGa1-&ITx&IT)2O3 alloy films on &ITc&IT-plane AlN templates by mist chemical vapor deposition

In this study, epsilon-(AlxGa1-x)(2)O-3 alloy films were grown on c-plane AN templates by mist chemical vapor deposition. The Al content of two samples was determined by Rutherford backscattering analysis. The lattice constant of the epsilon-(AlxGa1-x)(2)O-3 alloy films followed Vegard's law, and the Al contents of other samples were determined to be as high as x = 0.395 by Vegard's law. The direct bandgap was obtained in the range of 5.0-5.9 eV by transmittance measurements. The valence-band offset between epsilon-(Al0.395Ga0.605)(2)O-3 and epsilon-Ga2O3 was analyzed to be 0.2 eV, and the conduction-band offset was calculated to be 0.7 eV by X-ray photoelectron spectroscopy. The epsilon-(AlxGa1-x)(2)O-3/epsilon-Ga2O3 interface band discontinuity was type I. Our experimental results will be important for the actual application of epsilon-(AlxGa1-x)(2)O-3/epsilon-Ga2O3 heterojunction devices. Published by AIP Publishing.