Growth and optical properties of epitaxial BexZn1-xO alloy films

BexZn1-xO (0x0.28) alloy films were epitaxially grown by hybrid electron-beam deposition system. The crystal structure of the BexZn1-xO was investigated by X-ray diffraction pattern by varying the Be concentration. The crystal structure of the BexZn1-xO films was hexagonal within the variance of the Be component. Also, the phase separation within the BexZn1-xO alloy film was not observed. The photoluminescence emission peak of the BexZn1-xO films revealed the same pattern till the Be mole fraction increase up to x=0.11. When the Be mole fraction is larger than x > 0.11, the Ex(A) of free exciton at 3.624eV was only observed in the BexZn1-xO films. The band gap energy of the BexZn1-xO can be tailored from 3.30eV (x=0) to 4.13eV (x=0.28) by alloying ZnO with BeO. Throughout this band gap tuning, we may open the possibilities for fabricating ZnO-based ultraviolet light emitting diode utilizing the active layer comprised of ZnO/BexZn1-xO quantum well structure.