Junction Effect on Transport Properties of a Single Si Nanowire Metal-Semiconductor-Metal Device

We report measurements of electrical transport properties and impedance spectroscopy studies on a single Si nanowire (diameter similar to 50 nm) metal-semiconductor-metal device, fabricated using electron beam deposited Pt. The temperature-dependent four-probe resistivity of the nanowire exhibits freezing of carriers below 30 K, while at higher temperature, it resembles the temperature variation seen in bulk doped crystals. The device shows reproducible nonlinear and asymmetric current-voltage (I-V) characteristics which were quantitatively analyzed and were found to arise from unequal Schottky-type barriers at the two ends which also showed temperature dependence. The measured contact resistance is bias as well as temperature dependent and reduces as the bias is increased.