An ultra-sensitive nanocomposite pressure sensor patterned in a PDMS diaphragm

This paper introduces an ultra-sensitive pressure sensor with a flexible diaphragm apparatus. Conductive polymer nanocomposite consisting of elastomer poly (dimethylsiloxane) (PDMS) and carbon nanotubes (CNTs) is used as the sensing element utilizing its flexibility and piezoresistivity. Uniform dispersion of carbon nanotubes as nanofillers is obtained within the polymer matrix, and micropatterns of composite are fabricated through a screen printing process which is assisted by a programmable laser ablation. Mechanical and electrical characterizations are conducted on micropatterns. Under differential pressure across the diaphragm, the sensor device is capable of detecting minute change of pressure-less than 10 Pascal which is a significant improvement over current sensing capabilities. Provided with further development, this sensing format could yield potential applications in areas where accurate monitoring of air/liquid pressure is desired.