3D laser writing in-line process for the rapid fabrication of flexible electronic devices

Abstract

In this work, we present the fabrication of a strain sensor integrating a Wheatstone bridge made of organic resistors in only one step of patterning by using a promising approach of 3D direct laser writing. This processing method consists to adapt the power of the laser in function of the optical properties of the materials in order to pattern selectively, layer by layer, several materials in the same run. With this approach, we have achieved the fabrication of a piezoresistive sensor composed of a Kapton cantilever and a graphene strain gauge directly connected to a Wheatstone bridge integrating graphene resistor and copper conducting lines. The characterization of the resulting device has shown a high sensibility with a gauge factor of 20, proving the potential of this flexible piezoresistive sensor to be used for the development of low-cost flexible electronic devices like touch panels.