Eco-Conscious Approach to Wireless Gas Monitoring With a Hybrid Printed Passive Sensor Tag

Addressing the environmental impact of electronic waste in biomedical sensing, an eco-conscious approach to the realization of a Chitosan-based Acetone sensor tag for wireless gas monitoring is presented. The fabrication involves inkjet printing of silver electrodes and antennas on a bio-based, biocompatible, and biodegradable polylactic acid foil, as well as Chitosan coating for sensor functionalization. A hybrid approach is followed for the realization of the sensor readout by integrating a commercial, passive near-field-communication sensor chip on the printed sensor tag. Overcoming challenges in room temperature processing, the applicability and bonding adhesion strength of a commercial pressure-sensitive anisotropic adhesive film for flip-chip bonding is studied. With an average adhesion strength of 5.38 N, the proposed method exhibits great potential for ambient temperature flip-chip integration. Wireless measurements of the sensor show a linear response at an Acetone concentration between 0 and 31 ppm.