Fabrication and electrical characterization of silicon nanowire arrays

High density boron-doped silicon nanowire arrays were fabricated within the pores of anodized alumina membranes via vapor-liquid-solid (VLS) growth Anodized alumina membranes with a nominal pore diameter of 200 nm served as templates for the sequential electrodeposition of silver, cobalt, and gold which served as the backside electrical contact, ohmic contact metal and catalyst metal for VLS growth, respectively. Boron-doped silicon nanowires were then synthesized within the pores by VLS growth using silane (SiH ₄) and trimethylboron (TMB) gas sources. Arrays of Al dots were deposited on the top surface of the membrane after nanowire growth. A series of samples was prepared with different SiNW lengths and boron doping levels. Two point probe measurements were used to measure the I-V characteristics of the silicon nanowire arrays before and after annealing. Nanowire resistivity and contact resistance were determined from plots of resistance versus nanowire length. The resistivity of the SiNW was observed to decrease with the addition of TMB during growth.