ZnO thin film has been deposited on a sapphire (0 0 1) at a temperature of 400 °C using a pulsed laser deposition (PLD) with oxygen pressures of 50, 200, 300, 400 and 500 mTorr. The photoluminescence (PL) intensity of ultra-violet (UV) luminescence increases as the oxygen pressure increases up to 300 mTorr. This is probably because the stoichiometry of oxygen-deficient ZnO film is improved by increasing oxygen pressure. Stoichiometry of ZnO films has been more improved by O2 ambient annealing, but the textured micro-structure of the ZnO changes to the one with multi-orientation. The intensity of UV luminescence is generally proportional to the electrical resistivity and stoichiometry, but not much related to the micro-structures.
Bibliographical noteFunding Information:
Authors would like to thank Dr. J.H. Song of Korea Institute of Science and Technology for the backscattering spectrometry and also thank W. K. Choi of Korea Institute of Science and Technology for his sincere technical support. The authors wish to acknowledge the financial support of the Korea Research Foundation made in the program year of 1998 (1998-017-E00173).
All Science Journal Classification (ASJC) codes
- Condensed Matter Physics
- Physics and Astronomy(all)
- Surfaces and Interfaces
- Surfaces, Coatings and Films