Variable temperature photoluminescence of pulsed laser deposited ZnO thin films.

Autor: Cui, J. B., Soo, Y. C., Thomas, A., Kandel, H., Chen, T. P., Daghlian, C. P.
Předmět:
Zdroj: Journal of Applied Physics; Aug2008, Vol. 104 Issue 4, p043521, 6p, 1 Diagram, 1 Chart, 7 Graphs
Abstrakt: Variable temperature photoluminescence of ZnO thin films deposited by a reactive laser ablation of metallic zinc was investigated. Free and bound exciton emissions are absent at cryogenic temperature, and the near band edge (NBE) emission is independent of measurement temperature for the ZnO thin film deposited at room temperature. Annealing at 700 °C results in the removal of defects, reappearance of exciton emission, and a temperature dependent NBE emission. The experimental data suggest that defects play an important role in the band edge emission in terms of both spectra shape and temperature dependence. Our observations will have an impact on device applications using ZnO, especially for optoelectronics that utilizes the exciton emission. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index