Abstract:

Field-effect transistors based on silicon nanowires have been extensively used for sensing applications since the compact nanoscale structures allow excellent regulation of electrostatic potential across the nanowire channel. Sensors based on Junctionless Nanowire Transistors (JNT) have shown excellent sensitivity in liquid phases but they have not yet been operated in the gas phase. 

In this work, we report the fabrication and characterisation of silicon-based JNT devices and their initial tests as gas sensors. Silicon-on-insulator wafers are doped by ion implantation and flash lamp annealing. Device patterning is based on electron beam lithography, inductively-coupled reactive ion etching, metal deposition and lift-off. JNT sensor tests exhibited characteristic shifts in the transfer curve and a systematic increase and decrease of p- and n-type current, respectively, under the influence of different gases like NO2 and NH3 confirming potential suitability as gas sensors for detecting atmospheric radicals.

Additional Information: 

Sayantan Ghosh delivered this presentation for Deutschen Physikalische Gesellschaft e.V. (DPG) conference 2024.

RADICAL represents a 'Fundamental Breakthrough in Detection of Atmospheric Free Radicals'.

Find out more on the RADICAL project website: radical-air.eu

The RADICAL project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement number 899282.