InN nanowire based sensors

Abstract

High quality InN nanowires (NWs) were grown from nanoscale catalyst patterns by vapor-liquid-solid mechanism. The nanowires bend spontaneously or get deflected from other nanowires at multiples of 30º forming nano-networks. Smooth and planar NWs used to fabricate field effect transistors (FET) exhibited excellent drain current modulation in a back-gated geometry. The mobility calculated from the I-V characteristics is 36 cm 2 /Vs, while the carrier concentration is 4.8×10 18 cm -3 . The NW FET based nanosensor demonstrated high sensitivity to trace NO 2 due to a thin In 2 O 3 shell layer present around the InN core. The adsorption of the NO 2 molecules reduces the density of the carriers confined at the InN/In 2 O 3 interface, thus reducing the drain current. The change in drain current for a single NW based FET resulted in a very high sensitivity of 45 ppb in ambient conditions. Planar InN nano-networks can potentially offer a much improved sensitivity to trace NO 2 in ambient conditions.

Electrical transport and gas sensing characteristics of dielectrophoretically aligned MBE grown catalyst free InAs nanowires

“…The NWs show a significant change in resistance (106.5 Ω) upon exposure to NO 2 gas in the first cycle as shown in figure 7 and table 1. The increase in resistance is explained by the fact that NO 2 gas molecules have strong electron trapping capability upon adsorption to any surface [24,47]. The change in resistance during withdrawal of sensing gas and flushing the NWs with carrier N 2 gas is 25 Ω.…”

Gas Detection with Vertical InAs Nanowire Arrays

“…We tentatively attribute these effects to a reduced surface electron accumulation, and increased charging and scattering at InAs/In x O y interface states during NO 2 exposure. [29][30][31] Further studies 32 on the sensing mechanism as well as the concentration dependence of both the response time and rate are needed to clarify their relation InAs/In x O y interface.…”

Evolution of New Era in the Indian Politics

“…Internet facility is mostly available in the urban areas of India so its impact on the political scenario is inevitable. Currently only 15% of Indian population is using the internet out of which majority of the population using internet on their mobile phones [2].…”