Wasan R. Saleh, Nada M. Saeed, Wesam A. Twej, Mohammed Alwan
Physics Department, College of Science, University of Baghdad, Baghdad, Iraq.
DOI: 10.4236/ampc.2012.21002   PDF    HTML     9,768 Downloads   19,344 Views   Citations

Abstract

In this work, ZnO thin films were derived by sol-gel using two different techniques; dip coating and spin coating technique. The films were deposited onto glass substrate at room temperature using sol-gel composed from zinc acetate dehydrate, monoethanolamine, isopropanole, and de-ionized water, the films were preheated at 225?C for 15 min. The crystallographic structures of ZnO films were investigated using X-ray diffraction (XRD); the result shows that the good film was prepared at dip coating technique, it was polycrystalline and highly c-orientation along (002) plane, the lattice constant ratio (c/a) was calculated at (002), it was about 1.56. The structure of thin films, prepared by spin coating technique, was amorphous with low intensity and wide peaks. The optical properties of the prepared film were studied using UV-VIS spectrophotometer with the range 190 - 850 nm, and by using the fluorescence spectrometer. The optical characterization of ZnO thin films that were prepared by the dip coating method have good transmittance of about 92% in the visible region, it can be noted from the fluorescence spectrometer two broad visible emission bands centered at 380nm and 430 nm. The optical energy gaps for the direct and indirect allowed transitions were calculated, the values were equal 3.2 eV and 3.1 eV respectively. Dip coating technique create ZnO films with potential for application as transparent electrodes in optoelectronic devices such as solar cell.

Keywords

ZnO Thin Film; Sol-Gel; Dip and Spin Coating Technique

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Conflicts of Interest

The authors declare no conflicts of interest.

References

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