| Abstract |
| The vapor phase transport (VPT) process is usually used for the growth of one-dimensional nanostructures rather than for film deposition. In this study, for the first time, we report on the fabrication and optical propeties of ZnO film produced by VPT combined with rapid heating. The X-ray diffraction results showed that the intensity of the ZnO (002) peak was the largest, which indicated that the c-axis orientation of the ZnO grains was perpendicular to the substrate. In the photoluminescence (PL) spectra of the ZnO film at 12 K, PL peaks were observed at 3.374, 3.362, 3.319, and 3.242 eV, which were attributed to free excitons (FXs), excitons bound to neutral donors, donor-acceptor pairs (DAPs), and first-order longitudinal optical phonon replicas of DAPs (DAPs-1LO), respectively. The energy interval between DAPs and DAPs-1LO was almost the same as the longitudinal optical (LO) phonon energy of bulk ZnO of ~76 meV. The PL spectra in the temperature range from 12 to 300 K shifted to lower energy with an increasing temperature. The activation energy of FX was estimated to be 61 meV. This value is similar to the exciton binding energy of 60 meV. (Received September 4, 2015; Accepted December 11, 2015) |
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| Key Words |
| thin films, vapor deposition, optical properties, X-ray diffraction, photoluminescence |
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