Silicon on isolator ribbon field-effect nanotransistors for high-sensitivity low-power biosensor

Abstract

Silicon nanowire field-effect transistors are discussed as biological sensors due to their excellent sensitivity due to the large surface-to-volume ratio and high selectivity with respect to a large number of analytes. A miniature sensor based on a long-channel fin field-effect transistor as a surface charge detector is being investigated. The three-gate configuration offers undeniable advantages over planar devices, since the edges are about a hundred nanometers wide and are characterized by increased conductivity, which leads to higher sensitivity. The characteristics of the transistor are optimized using 3D modeling performed by the computer-aided design software package TCAD, depending on the topological parameters of the transistor and the level of control voltages. Based on the obtained simulation results, a chip was manufactured on a SOI substrate based on self-aligning CMOS-compatible technological processes from top to bottom. It is established that thin structures with a reduced level of doping and low supply power have promising electrical characteristics for an effective approach to scaling a high-resolution pH sensor, which is of particular interest to integrated pH bioanalytics based on CMOS technology.