Transient Simulation of Field-Effect Biosensors How to Avoid Charge Screening Effect

Abstract

We developed a numerical simulator to model the operation of a bio-FET in transient state. The simulator takes a realistic device structure as a simulation domain, and it employs the drift-diffusion equation for ion/ channel transport, and the Ramo-Shockley theorem for accurate calculation of non- faradaic current. For efficient transient simulation, the implicit time integration scheme is employed where the solution at each time step is obtained from the coupled Newton-Raphson method. Using the simulator, we found that the sensitivity of bio- FET can be improved with transient measurement by redistribution of the mobile ions by an external electric field.