Abstract
This paper offers new insights into the physical phenomena in light emission from ZnO. The effect of the annealing atmosphere and temperature on defect-related emission in ZnO thin films prepared by the sol-gel method and nonpolar ZnO bulk substrates is investigated by photoluminescence spectroscopy, transmission electron microscopy, and DC electrical measurements.
It is demonstrated that the post-annealing treatment is a powerful tool to modify intrinsic/extrinsic defects in ZnO and that the defect-related emission can be accurately tailored in a wide range from blue to red by changing the postdeposition processing parameters. Accurate tailoring of the deep-level emission wavelength in ZnO is of great importance in optoelectronics, particularly in white-light-emitting diodes, display devices, or biological labeling. [GRAPHICS] .