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Room Temperature Device Performance of Electrodeposited InSb Nanowire Field Effect Transistors

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 Added by Suprem Das
 Publication date 2011
  fields Physics
and research's language is English




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In this study, InSb nanowires have been formed by electrodeposition and integrated into NW-FETs. NWs were formed in porous anodic alumina (PAA) templates, with the PAA pore diameter of approximately 100 nm defining the NW diameter. Following annealing at 125C and 420C respectively, the nanowires exhibited the zinc blende crystalline structure of InSb, as confirmed from x-ray diffraction and high resolution transmission electron microscopy. The annealed nanowires were used to fabricate nanowire field effect transistors (NW-FET) each containing a single NW with 500 nm channel length and gating through a 20nm SiO2 layer on a doped Si wafer. Following annealing of the NW-FETs at 300C for 10 minutes in argon ambient, transistor characteristics were observed with an ION ~ 40 uA (at VDS = 1V in a back-gate configuration), ION/IOFF ~ 16 - 20 in the linear regime of transistor operation and gd ~ 71uS. The field effect electron mobility extracted from the transconductance was ~1200 cm2 V-1 s-1 at room temperature. We report high on-current per nanowire compared with other reported NW-FETs with back-gate geometry and current saturation at low source-drain voltages. The device characteristics are not well described by long-channel MOSFET models, but can qualitatively be understood in terms of velocity saturation effects accounting for enhanced scattering



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