Behavior Study of Annealing Temperature on Microstructure and Wettability of Electrodeposited ZnO Thin Films for Microcapacitor Application

Abstract

In this work, electrodeposition was used to produce thin zinc oxide layers on n-type silicon substrates. It has been investigated how annealing at 400∘C affects the deposit's morphological and structural characteristics. SEM, X-ray diffraction, and contact angle measurements have all been used to study the morphology and structure of nonannealed and annealed ZnO. Three intense peaks were visible in the XRD patterns of non-annealed ZnO thin films along the (100), (002) and (101) planes, however these peaks' intensities were different in the XRD patterns of annealed ZnO layers. Furthermore, the 2θ diffraction angle shift can be seen in the XRD patterns of annealed and unannealed ZnO layers. The contact angle measurements showed that the nonannealed ZnO layers are hydrophobic; however, at a temperature of 400∘C for annealing, the ZnO layer surface becomes hydrophilic. Finally, SEM data validate the XRD and contact angle findings by showing how ZnO structure changes from a sand rose shape to a granular structure. Additionally, the ZnO/n− Si micro-capacitor device has been developed and impedance spectroscopy (EIS) has been used to evaluate it. Finally, a microcapacitor made of ZnO and n−Si showed a high specific capacitance of 128mF/g.