FET based nano-pore sensing: a 3D simulation study

We report the development and testing of simulation software, which, combining self-consistent Brownian dynamics and Drift Diffusion simulation techniques in a single simulation domain allows the simulation of the effect of ions and charged molecules on the current flowing through a sensing FET. For sensory applications an aqueous solution is introduced above the transistor gate dielectric and the effect of fixed charges on the transistor current is investigated. We significantly extend previous work (Moore et al. in Proceedings of the 11th International Conference on Ultimate Integration on Silicon, pp. 85-88, 2010) by analysing the effects of mobile ions on the system and introduce an initial analysis of the noise associated with the Brownian motion of mobile ions in the solution in order to determine the sensitivity of the FET in measuring the position and number of ions. Finally, results are presented showing the sensitivity of the drain current to the movement of a single ion through a nano-pore.