Electrodeposited AlSb compound semiconductor for thin film solar cells

AlSb thin films have been electrodeposited on mesoporous TiO₂ on ITO (In₂O₃:SnO₂) coated glass surface. The reduction potential of aluminum and antimony from a solution of SbCl₃ in an AlCl₃/EMIC ionic liquid and SbCl₃ was determined by cyclic voltammetry to be -0.62 V and 0.54 V respectively. The deposition of AlSb compound was accomplished by reversing the reduction pulsed potential cycles. Thin film solar cells with p - n and p - i - n heterojunction was fabricated using n type TiO₂ layer and the AlSb absorber layer. This p - n heterojunction (AlSb/TiO₂) solar cell was simulated by AMPS and shows a maximum conversion efficiency of ~19 %. Also, a p - i - n heterojunction solar cell has been designed by using AlSb layer as an intrinsic absorber. The p - i - n heterojunction (CuSCN/AlSb/TiO₂) structure was fabricated by depositing p type CuSCN layer on top of AlSb layer. The simulation results show an efficiency ~ 14.4% with a thin AlSb absorber layer of ~500 nm. The characterization of these AlSb based devices is still under investigation.