A study of the size effect on the temperature-dependent resistivity of bismuth nanowires with rectangular cross-sections

摘要

Rectangular cross-section bismuth nanowires with dimensions of 50 nm by 70-200 nm (thickness by width) were fabricated using an electron beam writing technique. Individual nanowire measurement is possible using this method. The resistivities of the 50 nm thick nanowires were dependent on line width. The measured resistivity of 70, 120 and 200 nm wide nanowires was 4.05 x 10~(-3), 2.87 x 10~(-3) and 2.30 x 10~(-3) OMEGA cm at 300 K respectively. Temperature-dependent resistance measurements indicated that the electrical conductivity of the Bi nanowires was carrier dependent, and the carrier density decreased at low temperature, showing that the all the Bi nanowires exhibited semiconductor behaviour. The size-dependent resistivity of the Bi nanowires was an indication of the ordinary size effect in the one-dimensional nanowire, where the carrier mobility was grain boundary scattering dominated.