Effect of Annealing Temperature on Structural and, Morphological Properties of Zno Thins Films

Abstract

In this work, thins films of zinc oxide were deposited on n-type silicon substrates by chemical electrodeposition. The effect of annealing temperature from 200 ° C to 600 ° C, with a step of 100 ° C, on the structural and morphological properties of ZnO layers has been studied. Scanning electron microscopy (SEM), X-ray diffraction (XRD) and contact angle measurements were used to characterize the morphology and structure of ZnO without and with annealing. The XRD patterns of unannealed ZnO thins films indicate the presence of three intense peaks along (100), (002) and (101) planes, while for the annealed ZnO layers the XRD patterns show also the three major peaks but the intensity of these peaks is increased except for a temperature of 600 ° C where is decreased. The comparison of the XRD patterns of the ZnO layers without and with annealing, reveal a shift in the 2θ diffraction angle, the calculation of the crystallinity confirms the obtained results. The contact angle measurements indicate that the ZnO layers without and with annealing at 200 °C are hydrophobic, the surface of the ZnO layer becomes hydrophilic at annealing temperatures exceeding 300 ° C. Finally, SEM images show the change in structure from a sand rose shape to a granular structure, confirming the XRD and contact angle results.