Fabrication and characterization of a pressure sensor using a pitch-based carbon fiber

Abstract

The principal and innovative concept of this research is the replacement of piezoresistors in the current piezoresistive pressure sensors with carbon fibers. The piezoresistive characteristics of carbon fibers can play the same role as piezoresistors in current pressure sensors. The main structure of pressure sensors was built by backside etching on a silicon-on-insulator wafer to create a square diaphragm. Dielectrophoresis was used for the alignment and deposition of carbon fiber across the gap between two electrodes. The fabricated pressure sensors clearly showed linear response to applied pressure, so the feasibility of carbon fiber-based pressure sensors was demonstrated.