We have investigated electrical properties of indium phosphide nanowire field effect transistors with four different types of metal electrodes (Cr, Ti, Au, and Pt). The nanowires with a width of 50 nm were undoped and grown by metal-organic chemical vapor deposition. Among the four types of metal electrodes, Cr/InP and Ti/InP showed ambipolar conduction, while Pt/InP and Au/InP exhibited p-type conduction. Extracted Schottky barrier heights suggest that barrier heights do not vary linearly with respect to the metal workfunction. Although the Pt/InP features the smallest barrier height, the Au/InP showed the highest drain current at a given gate bias.
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