One-step patterning of a flexible piezoresistive MEMS sensor by 3D direct laser writing

In this work, we present for the first time a new fabrication process based on a 3D direct laser writing technique which allows the patterning of several layers in a single step by adjusting the power supplied by the laser in function with the optical properties of the materials. This approach was used for the fabrication of a piezoresistive MEMS (Micro Electro-Mechanical System) sensor made of flexible substrate whose three constituting layers were designed in the same step. The characterization of the resulting graphene strain gauge integrated in a Kapton microcantilever has shown a high sensibility since a gauge factor of 20 was obtained, proving the potential of the fabricated flexible piezoresistive MEMS to be used as transducer for the development of low-cost sensing platforms.