The Effect of Thermal Annealing Processes on Structural and Photoluminescence of Zinc Oxide Thin Film

Abstract

This study used radio frequency sputtering at room temperature to prepare a zinc oxide (ZnO) thin film. After deposition, the thin film was placed in a high-temperature furnace to undergo thermal annealing at different temperatures (300, 400, 500, and 600°C) and for different dwelling times (15, 30, 45, and 60 min). The objective was to explore the effects that the described process had on the thin film’s internal structure and luminescence properties. A scanning electron microscope topographic image showed that the size of the ZnO crystals grew with increases in either the thermal annealing temperature or the dwelling time. However, significant differences in the levels of influence caused by increasing the thermal annealing temperature or dwelling time existed; the thermal annealing temperature had a greater effect on crystal growth when compared to the dwelling time. Furthermore, the crystallization directions of ZnO (002), (101), (102), and (103) can be clearly observed through an X-ray diffraction analysis, and crystallization strength increased with an increase in the thermal annealing temperature. The photoluminescence measurement spectra showed that ultraviolet (UV) emission intensity increased with increases in thermal annealing temperature and dwelling time. However, when the thermal annealing temperature reached 600°C or when the dwelling time reached 60 min, even exhibited a weak green light emission peak.

Reduction of hazardous reactive oxygen species (ROS) production of ZnO through Mn inclusion for possible UV-radiation shielding application

“…Figure 2 shows the XRD patterns of Mn x ZnO (1-x) samples at different Mn content (x ¼ 0, 2 and 6 at. %), which were post-annealed at 300 C. The purpose of annealing was to enhance crystallinity of the samples [31]. The visible peaks of (100), (002), (101), (102), (110), (103), (200), ( 112) and (201) crystallographic planes were indexed to hexagonal wurtzite ZnO structure across all samples, and found to match that of COD 2013 database ID COD 9004180.…”

Temperature-Driven Structural and Morphological Evolution of Zinc Oxide Nano-Coalesced Microstructures and Its Defect-Related Photoluminescence Properties

“…There is little research reporting the achievability of growing ZnO at comparatively low temperature utilizing the liquid phase growth methods such as hydrothermal synthesis and sol-gel processing. However, there are some drawbacks relating to these processes in contrast to the thermal evaporation method, such as: (i) these methods demanded additional fabrication step, for example furnishing a seed layer by physical methods prior to the actual synthesis [ 14 ]; (ii) these methods required a precise control of the composition, pH, and also concentration of an electrolyte solution; (iii) the growth rate of these methods was inferior to the vapor phase process [ 15 ]; and (iv) these methods needed a post thermal annealing treatment to alter the thin film’s internal crystallization and concurrently reduced the defects in the thin film and then prevented the growth of other crystalline phases [ 16 ].…”

The effect of millisecond flash lamp annealing on electrical and structural properties of ZnO:Al/Si structures

“…The reflection cannot be unambiguously assigned to any phase consisting of the elements Zn, Al, Si, or O, listed in standard power diffraction, ICDD, cards. One can speculate that it can be a ZnO ð10 11Þ 27,28 or Al 2 O 3 (104) reflection at 36.25 or 35.15 . The latter can be theoreticized to be due to Al segregation.…”