An in-situ hybrid laser-induced integrated sensor system with antioxidative copper

Abstract Integration of sensors with engineering thermoplastics allows to track their health and surrounding stimuli. As one of vital backbones to construct sensor systems, copper (Cu) is highly conductive and cost-effective, yet tends to easily oxidize during and after processing. Herein, an in-situ integrated sensor system on engineering thermoplastics via hybrid laser direct writing is proposed, which primarily consists of laser-passivated functional Cu interconnects and laser-induced carbon-based sensors. Through a one-step photothermal treatment, the resulting functional Cu interconnects after reductive sintering and passivation are capable of resisting long-term oxidation failure at high temperatures (up to 170 °C) without additional encapsulations. Interfacing with signal processing units, such an all-in-one system is applied for long-term and real-time temperature monitoring. This integrated sensor system with facile laser manufacturing strategies holds potentials for health monitoring and fault diagnosis of advanced equipment such as aircrafts, automobiles, high-speed trains, and medical devices.