Effect of Annealing on Al-Sb Multilayer Films

The metallic films of Al and Sb were deposited alternately on quartz glass substrates by magnetron sputtering method and then annealed at high-temperature in vacuum to obtain AlSb polycrystalline.The structural,electrical and optical properties of the films before and after annealing were studied with X-ray diffraction(XRD),Hall effect,the temperature dependence of the dark conductivity and UV-Vis transmission and reflection spectra.XRD results show that Al-Sb multilayers transform to AlSb polycrystalline cubic phase films with preferred orientation in(111) direction.The measurement results indicate that the annealed AlSb films are P-type semiconductor with the carrier density of 1019cm-3 and the absorption coefficient is higher than 104cm-1 in the visible light.After annealed at 580℃,the indirect energy band-gap of the AlSb film is about 1.64eV.During the temperature increasing process,the conductivity activation energy Ea is 0.01 and 0.11eV.The open circuit voltage of 107mV is achieved in TCO/CdS/AlSb/ZnTe:Cu/Au devices,which demonstrates the potential of AlSb as the absorber layer in solar cells.