Novel synthesis of ZnO thin films by facile solution process

Abstract

A facile solution process to synthesis ZnO thin films was successfully conducted in this work. Zinc acetate dihydrates were used as the main precursor, dissolved in the mixture of acetylacetone and ethanol whichact as solvent and precursor simultaneously. This mixture deposited by spin coating and dried under ambient atmosphere at room temperature. The reaction mechanism, structure, morphology, chemical composition and optoelectrical properties of the resulted ZnO thin film were studied. The as deposited films were annealed at 500 °C for 2 h under O2 gas flow added with H2O vapor and CO2 gas. The ZnO thin films showed a dense, homogenous morphology and high transparency. The film is an n-type semiconductor with 3.18 eV bandgap, has 1.25 × 10−19 cm3 carrier concentration, 12 cm2/Vs electron mobility and 2.42 × 10−3 Ω·cm resistivity making it suitable for application as window layer in a photovoltaic cell.

Keywords

• ZnO
• Thin films
• Spin coating
• H2O vapor
• CO2 gas
• Acetylacetone