Fabrication of Low-Cost and Highly Sensitive Graphene-Based Pressure Sensors by Direct Laser Scribing Polydimethylsiloxane.

The cost-effective production of flexible interconnects is a challenge in epidermal electronics. Here we report a low-cost approach for producing and patterning graphene films from polydimethylsiloxane films by direct laser scribing in ambient air. The produced graphene films exhibit high electrical conductivity and excellent mechanical properties and can thus be used directly as a flexible conductive layer without the need for metals. The skinlike pressure sensor with these layers exhibits ultrahigh sensitivity (∼480 kPa-1) while maintaining the fast response/relaxation time (2 μs/3 μs) and excellent cycle stability (>4000 repetitive cycles). Moreover, it can naturally attach to the skin to monitor the wrist pulse. In addition, a 7 × 7 sensor array has been fabricated, which possesses the capability to detect the spatial distribution of pressure. This device has great potential for application in epidermal electronics because of its low cost and high performance.