Journal of Crystal Growth, Vol.303, No.2, 506-509, 2007
Growth and optical properties of epitaxial BexZn1-xO alloy films
BexZn1-xO (0 <= x <= 0.28) 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 BexZnl-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 3.624 eV was only observed in the BexZn1-xO films. The band gap energy of the BexZn1-xO can be tailored from 3.30 eV (x = 0) to 4.13 eV (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. (C) 2007 Elsevier B.V. All rights reserved.
Keywords:band gap energy;hybrid electron-beam deposition;beryllium;BexZn1-xO;ultraviolet light emitting