Sol-gel preparation of Zn-V-Mn-O thin films for low voltage varistor applications

ZnO-based thin films in the Zn-V-Mn-O system have been synthesised by a sol-gel process and characterised for use in low voltage varistor applications. The films were prepared through multi-layer deposition of a precursor solution onto indium tin oxide-coated borosilicate glass substrates by spin-coating and subsequent annealing. Current-voltage characteristics measured for the films annealed at 700 °C showed varistor action with nonlinear coefficients (α) above 4.