Highly sensitive electrical detection of TCNE on chemically passivated silicon-on-insulator

Abstract

Adsorption of tetracyanoethylene (TCNE) onto hydrogen terminated, n-type silicon-on-insulator is shown to cause significant depletion of majority carriers. Employing an ambient pseudo-MOSFET, ppm levels of TCNE vapour rapidly decrease the n-channel saturation current by at least two orders of magnitude. Covalent passivation with a decyl monolayer improves the reversibility of the response while only slightly decreasing the sensitivity.