The structural properties of Al doped ZnO films depending on the thickness and their effect on the electrical properties

► We studied the structural and electrical properties of AZO films with different film thickness. ► Grain size increases and stress decreases with thickness increase, leading to enhanced crystallinity. ► Grain size dependence of stress follows the same tendency for all samples regardless of deposition temperature. ► Defects at grain boundary are reduced with increase of film thickness or deposition temperature. ► The mobility increase is accompanied by grain size increase and compressive stress reduction.