Investigation of properties of ZnO and MgxZn1-xO films prepared by sol-gel method

•The crystalline quality of the ZnO film increases as the film thickness increases, and the resistivity decreases accordingly.•As the annealing temperature increases, the crystalline quality of the ZnO film first improves and then decreases.•No phase separation occurs when the doping concentration reaches 30% by sol-gel method.•The band gap of MgZnO films increases linearly with the increase of Mg doping.•The resistivity of MgZnO films decreases with increasing Mg doping concentration.