Crystalline and transport properties of Ga2Te3 synthesized by metalorganic chemical vapor deposition

Ga 2 Te 3 films have been grown on GaAs(100) and (111) substrates using metalorganic chemical vapor deposition (MOCVD) at temperatures ranging from 350°C to 450°C. Very uniform films were grown at lower temperatures of 350°C on GaAs(100) substrates. As the temperature increased the roughness of the films increased, with many hillocks observed on films deposited at 450°C. The Ga 2 Te 3 films grown on GaAs(100) were determined to be single crystal by XRD characterization. On the other hand, XRD scans confirmed crystal twinning in the Ga 2 Te 3 films grown on GaAs(111) and the surface morphology also indicated the presence of twin grains. The films were determined to be n -type by hot-point probe testing. The carrier concentration could not be measured precisely as after photoexcitation, Ga 2 Te 3 exhibited the persistent photoconductivity (PPC) effect.