Integration of laser-induction and electroless copper plating for flexible electronics

Integration of flexible conductive electrodes and components is a critical technology for advancing smart wearable electronics. However, the intricate fabrication process, mechanical mismatch, and weak interface bonding for electronics integration often hinder its practical application. Here, we report a facile strategy that combing laser-induced graphene and electroless copper plating to integrate high-performance planar and curved flexible circuits for human physiological signals monitoring. The laser-induced copper patterns and porous graphene serve as flexible electrodes and functional components, respectively. As a result, the laser-induced patterned copper exhibits excellent electrical conductivity (0.037 Ω/sq), electrical stability (∼2 % variation over 30 days) and a high interface bonding strength at the 5B level. As a demonstration, the copper conductors and graphene components achieve seamless integration within planar and curved flexible substrates. The integrated prototype device demonstrates superior conformability, ensuring precise signal detection. This method sheds a new light on high-performance wearable devices in physiological signal monitoring.