In this paper, we present the properties of new type of material ZnO and the ZnO films prepared on sapphire substrate through atomic layer deposition (ALD). In experiment, we use N2 as the carrier, DEZn and DI-water as the precursors. The deposition temperature is 180℃. The value of Zn/O could be modified through changing the dose of DEZn. Furthermore, we investigate the influences of Zn/O value on the thickness, growth rate, crystalline property, surface morphology, three-dimensional structure and roughness of the ZnO film prepared by the ALD method.