Recombination dynamics of excitons in Mg0.11 Zn0.89 O epilayers grown by laser-assisted molecular-beam epitaxy on a ScAlMg O4 substrate were investigated. By using the MgZnO high-temperature-annealed self-buffer layer (HITAB), the value of full width at half maximum of the near-band-edge (NBE) photoluminescence (PL) peak at 3.6 eV was decreased from 133 to 94 meV at 293 K, and the intensity ratio of the NBE emission to the deep emission band centered around 2.2 eV was increased by a factor of 3. Also, the PL lifetime of the NBE peak at 293 K under the excitation density of 1 μJ cm2 was increased from 49 to 60 ps. These results suggest that HITAB gave rise to improved alloy compositional homogeneity and reduced concentration of point defects.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)