Ab initio study of sensing mechanism of CNT-based FET sensor
Ki-jeong Kong
Korea Research Institute of Chemical Technology, Daejeon 305-600, Korea
Electronics based on carbon nanotubes (CNT) and semiconducting nanowires have received a lot of attention recently because of its tremendous application potential, such as active components in nanochips, nanoelectromechanical systems, field-emission display devices, and chemical and biological sensors. However, as with most nanoelectronic systems, successful commercial materialization needs accurate structural control at the molecular level. To this end, computer-aided material design is clearly necessary to understand operation principles, to avoid blind investigation by trial-and-error, and to find more efficient and economic ways to the materializations.
This talk summarizes our computational efforts to address the sensing mechanisms of nanosensors fabricated and operated at KRICT. Examples include the gas sensor of NH3 and NO2, palladium coated CNT sensor that interacts with H2 molecules, and the humidity sensor made of CNT field effect transistor (FET.) Our approach is based on first-principles density functional theory (DFT) to compute equilibrium structures, electronic density of states, and charge transfer by Muliken analysis.