Studying on the Preparation and Characteristics of Al2O3-Based Textured ZnO Thin Films

Using the magnetron sputtering technology, high quality Al2O3-based textured ZnO thin films (Al2O3/ZnO) which can be applied to solar cells' light trapping effect were fabricated by controlling the preparation parameters properly. X-ray diffraction (XRD) and Scanning electron microscopy (SEM) results show that O2 /(Ar+O2) flow ratio has great influence on Al2O3/ZnO films surface morphology during Al2O3 layer growth, the Al2O3/ZnO films with pyramid structure morphology were easily prepared as O2 /(Ar+O2) flow ratio is in the range of 16.7%~50%. According to the measurement results of Al2O3/ZnO films' resistivity and UV-Visible transmission spectra, the lowest resistivity of 0.0048Ωcm and optical transmission of larger than 80% were obtained for these Al2O3/ZnO films in this paper. After treated up to 720h under harsh environmental condition with relative humidity of 85°C and temperature of 80°C, these samples conductivity degradation is in the range of 12%~14% for Al2O3/ZnO films, which indicates that the Al2O3/ZnO films have better stability compared to ZnO films.