Surface wetting of silver-doped sol–gel ZnO films

Abstract

Zinc Oxide thin films were fabricated by sol-gel process and treated with various organic solvents between deposition layers. Undoped and silver-doped samples were further subjected to different drying and annealing temperatures between coats. Effects on surface morphology, preferred crystallographic orientation, crystallite size, and change in calculated optical band gap were all examined factorially by dopant, annealing, and wetting/treatment. Nearly every wetting solvent was found to improve preferential orientation and crystallinity, although significant differences were observed between doped and undoped, interstitially annealed samples, and those not annealed between layers. Direct causal correlation is not examined herein, although some inference can be made as to the effects of wetting solvents' intermolecular energy, polarity, viscosity, surface energy, and other intrinsic properties. Significant improvements in film properties suggest that further research into wetting-treatment methods is warranted, in terms of electronic and semiconductive character, and deviceimplementation.

Effect of deposition time on properties of the ZnO by USD Method

“…It is widely used for numerous applications such as gas sensors [11], biosensors [12], drugs, cosmet-ics, storage, optical and electrical devices, solar cells [13], and biomedical applications [14][15][16][17]. To deposit ZnO thin film, several methods have been often used such as chemical vapor deposition [18,19], pulsed laser deposition [10,20], atomic layer deposition (ALD) [21,22], spray pyrolysis [13], RF magnetron sputtering [23,24], plasma spraying [25], dipcoating method [26], electron beam (e-beam) evaporation [27], chemical bath deposition [28], chemical oxidative polymerization [29], plasma electrolytic oxidation (PEO) [30], electrophoretic deposition (EPD) [31], and sol-gel [32], etc. Among these methods, we are going to focus on the spray ultrasonic technique [33] because of its simplicity and suitability for large-scale production.…”