Exploitation of Giant Piezoresistivity – CNT Sensors Fabricated with a Wafer-level Technology

Abstract

Here we present a holistic wafer-level approach for the fabrication of highly sensitive electromechanical transducers, using the intrinsic piezoresistive effect of enriched semiconducting single-walled carbon nanotubes (SWCNTs). Therefore membrane based demonstrators were fabricated on 150mm wafers using MEMS compatible micromachining. Carbon nanotube field-effect transistors were positioned at membrane sites with the highest strain upon pressure driven actuation. The giant piezoresistive effect of SWCNTs was proved and quantified. We derived the gauge factor to be more than 600, which is significantly higher than for common silicon strain gauges.