InN is an attractive material for novel nanoscale optoelectronic devices due to its low band gap and superior transport
characteristics. Recently, Chang et al. [J. Electron. Mater. 35, 738 (2006)] presented measurements showing an
anomalous resistance observed for InN nanowires with diameters less than 90nm. We examine possible theories
presented in literature to explain the extraordinary observation and propose a possible explanation for the reported
observations based on the unique attribute of InN − high density surface electron accumulation layer. The presence of
high density accumulation layer at the surface leads to two distinct conduction mechanisms in InN viz. surface and bulk.
For large diameter InN nanowires, bulk conduction is proposed to be the dominant mechanism whereas in small
diameter nanowires both surface and bulk conduction contribute to carrier transport.
We demonstrate an InP nanowire based photodetector laterally integrated between two (111)-oriented vertical silicon surfaces. The nanowires are grown through a simple single step chemical vapor deposition (CVD) process using gold nanoparticles as catalyst with
in-situ p-doping and have been heteroepitaxially bridged between a pair of prefabricated p-doped Si electrodes. Nonlinear current-voltage characteristics are observed. Although this nonlinearity resembles a back-to-back rectifying profile it originates from space-charge limited conductivity of the nanowires. DC photoelectric characteristics of the device were measured under optical illumination (λ=630 nm) above the bandgap energy (1.34 eV or ~925 nm at room temperature) of InP. The variation in photoconductance with varying input optical power demonstrates high sensitivity of the device to optical illumination.