The development of a pressure sensor using a technique for patterning silver nanowires on 3-dimensional curved PDMS membranes

Abstract

The development of flexible electronic devices has primarily been focused on the production of flat 2-dimensional sensors and has lacked the ability to manufacture devices with complicated 3-dimensional geometry. A mold-based method for manufacturing devices with 3-dimensional geometry that is cost-effective and repeatable is presented herein. This technique is demonstrated by the fabrication of a novel pressure sensor using a 3-dimensional PDMS membrane patterned with a resistive silver nanowire network. The specific geometry of the sensor was chosen to provide a uniform strain distribution along the silver nanowire network. The sensor has a linear response to pressure, a gauge factor of 4–29, and behaves well under repeated cyclical testing. A flat sensor with a 2-dimensional membrane was also manufactured for comparison to the 3-dimensional sensor. It was observed that the flat membrane has a higher gauge factor but has a non-linear response to pressure.