Metalorganic vapor-phase epitaxial growth and photoluminescent properties of Zn1−xMgxO(0⩽x⩽0.49) thin films

High-quality ${\mathrm{Zn}}_{\text{1−x}}{\mathrm{Mg}}_x\mathrm{O}\text{(0.00⩽x⩽0.49)}$ thin films were epitaxially grown at 500–650 °C on ${\mathrm{Al}}_{\mathrm{2}}{\mathrm{O}}_{\mathrm{3}}\mathrm{(00\cdot 1)}$ substrates using metalorganic vapor-phase epitaxy. By increasing the Mg content in the films up to 49 at. %, the c-axis constant of the films decreased from 5.21 to 5.14 Å and no significant phase separation was observed as determined by x-ray diffraction measurements. Furthermore, the near-band-edge emission peak position showed blueshifts of 100, 440, and 685 meV at Mg content levels of 9, 29, and 49 at. %, respectively. Photoluminescent properties of the alloy films are also discussed.