E-skin module with heterogeneously integrated graphene touch sensors and CMOS circuitry

This paper presents a flexible electronic skin (e-skin) module developed by heterogeneous integration of graphene based touch sensors and CMOS chips having basic capacitance-to-voltage converter (CVC) circuitry to acquire the sensor response. Graphene touch sensor was firstly transfer printed on a flexible polyvinyl chloride (PVC) substrate, thereafter the CMOS chip with 4x4 array of large transistors was integrated on the same PVC substrate. Then, resulting module was tested to verify the performance. The heterogeneous integration of graphene and Si based devices on the same flexible substrate is an interesting new approach that can be scaled up, opening a new opportunity for obtaining large area e-skin for robotic applications.