Rootlike Morphology of ZnO:Al Thin Film Deposited on Amorphous Glass Substrate by Sol-Gel Method

Heri Sutanto,Singgih Wibowo,Hady Hadiyanto,Sufwan Durri,Eko Hidayanto

doi:10.1155/2016/4749587

Abstract

Zinc oxide (ZnO) and aluminum doped zinc oxide (ZnO:Al) thin films have been deposited onto a glass substrate by sol-gel spray coating method at atmospheric pressure. X-ray diffractometer (XRD), scanning electron microscopy (SEM), and UV-Vis spectrophotometer have been used to characterize the films. XRD spectra indicated that all prepared thin films presented the wurtzite hexagonal structure. SEM images exhibited rootlike morphology on the surface of thin films and the shortest root diameter was about 0.219 μm. The UV-Vis absorption spectra exhibited the absorption edges that were slightly shifted to the lower wavelength. From this result, the incorporation of aluminum into the ZnO involved a slight increase in the optical band-gap of films. The optical bands of films were 3.102 eV, 3.115 eV, 3.118 eV, 3.115 eV, 3.109 eV, and 3.109 eV for ZnO, ZnO:Al 2%, ZnO:Al 4%, ZnO:Al 6%, ZnO:Al 8%, and ZnO:Al 10%, respectively. Increase of Al doping concentration in ZnO films contributed to the increase of their optical band-gap which can be explained by the Burstein-Moss effect.

Highlights

Zinc oxide (ZnO) is the most popular materials that can be used for many applications
We proposed ZnO and ZnO:Al thin films deposited by sol-gel spray coating
The pattern demonstrates that the obtained thin films have sharp and narrow peaks, indicating that the materials exhibit high crystallinity

Summary

Introduction

Zinc oxide (ZnO) is the most popular materials that can be used for many applications. Many researchers have studied this material for electronics [1], energy [2], and environment [3] applications. ZnO is of low cost and nontoxic and has high chemical stability which make this material so interesting [4]. ZnO has a wide bandgap energy (∼3.3 eV) and has been studied in different forms such as powder [10] and thin film [11]. Several techniques can be used to make ZnO:Al thin film, such as DC or RF magnetron sputtering [12, 13], electron beam evaporation [14], pulsed laser deposition [15], chemical vapor deposition [16], spray pyrolysis [17], and sol-gel processing [18]. Sol-gel is the most widely used method because of its easy and low-cost preparation [19]

Methods

Results

Conclusion