TUD

Silicon nanowire based field effect transistors (FETs) are building blocks of future highly sensitive chemical detectors. Silicon nanowires grown with catalytic chemical vapor deposition (CVD) exhibit Schottky barriers after contacting them to metal leads. External electric fields can manipulate the barrier shape in a very efficient way. Thus charge carrier transport through the Schottky junction is highly sensitive to surface bio-functionalization. However, currents of a single nanowire FET with diameter of 20nm are limited to approximately 1A. One of the requisites to build nanowire sensors with signal outputs that can be read by conventional electronics is to integrate a sufficiently high amount of nanowires in parallel. Here, a concept of parallel nanowire integration that delivers a high active area and a system with high-currents is presented. Significant signal enhancement as required for a feasible bio sensing system can be reached without altering the electrical characteristics.