Structural and physical characterisation of zinc oxide thin films prepared from zinc acetate via the sol-gel method

The influence of zinc acetate concentration in the range 0.3-1.3M and annealing temperature in the range 450-550°C on the microstructure of zinc oxide films prepared by the sol-gel method was investigated. Zinc acetate concentration of the sol-gel deposited was found to be the major influence on the microstructure and in particular c-axis or (002) preferred orientation of the resulting film, due to its impact on film thickness, for a single sol-gel deposition employing fixed deposition conditions. Preferentially (002) orientated films were obtained from 0.3M zinc acetate sol-gels. However, an increase in zinc acetate concentration resulted in an increase in film thickness and a loss of preferential (002) orientation. It was found that thick preferentially (002) oriented films could be produced by using multiple depositions of a 0.7M zinc acetate sol-gel using higher drying temperatures.