The sol-gel method was used to obtain ZnO films doped with Sn at different annealing temperatures, 400°C, 500°C and 600°C. As a starting material, zinc acetate dehydrate was used, with 2-methoxyethanol and monoethanolamine as the solvent and stabilizer, respectively. The dopant source was tin chloride. The amounts of dopant in solution were Zn1-xSnxO: x = 0 and 5at.%. The proportion of dopant and Zn atoms are not the same in the film and in the solution. In other cases, the dopant proportion in the film is less than that in the solution. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray (EDX), UV-VIS spectroscopy and Raman spectroscopy were used to study the structural, surface morphological and optical properties of the films and the molecular bonding of the ZnO, respectively. It was concluded that the dopant amount, as well as the annealing temperature, modifies the film growth process and consequently the microstructure and surface morphology as well as the optical properties.