Single crystalline α-axis ZnO thin films deposited by sol-gel method for optoelectronic devices

Undoped alpha-axis oriented single crystalline zinc oxide (ZnO) films were deposited by sol-gel dip-coating method. The films were characterized by X-ray diffraction (XRD) and ultraviolet visible (UV-VIS) absorbance spectra. The films of ZnO were deposited on amorphous microscopic glass substrate at various temperatures. The XRD showed that the ZnO film was crystallized with a hexagonal structure with a strong orientation in the (100) plane, which is exactly along the a-axis and beneficial for the development of optoelectronic devices. The optical band gap energy found for this a-axis oriented ZnO film was 3.30 eV through UV-VIS absorbance spectra. The Fourier Transform Infrared Spectroscopy (FTIR) analysis was carried out by taking the IR absorbance spectra for ZnO film deposited on the silicon substrate at 450 degrees C. It showed that the strong Zn-O stretching bond is present in the deposited film.