Tuning Electrical and Photoelectrical Properties of CdSe Nanowires via Indium Doping

A systematic study on preparing n-type CdSe nanowires (NW) with tunable conductivity was presented and the photoelectrical characteristics of the doped NWs were investigated. In situ doping by introducing indium dopant during NW growth and post-growth doping by annealing the NWs in indium vapor was carried out for indium doping of CdSe NWs. The results show that the CdSe NWs are clean and smooth without visible particles and impurities and the diameter and length of the NWs are in the range of 50-120 nm and 10-100μm. The conductivity of undoped CdSe NWs measured by the four-probe method is found to be one order of magnitude lower than that of undoped CdSe films prepared by vacuum evaporation. The spectral response of the doped CdSe NWs demonstrate that sensitivity is the highest around 710 nm and decreases at longer light wave-lengths.