Printing Stretchable Spiral Interconnects Using Reactive Ink Chemistries

Stretchable electronics have important applications in health monitoring and integrated lab-on-a-chip devices. This paper discusses the performance of serpentine stretchable interconnects printed using self reducing, silver reactive inks. It details process optimization, device fabrication, and device characterization, while demonstrating the potential applications for reactive inks and new design strategies in stretchable electronics. Devices were printed with an ethanol stabilized silver diamine reactive ink and cycled to stretch ratios of 140 and 160% over 1000 cycles with less than 2.5% variation in electrical resistance. Maximum deformation before failure was measured at 180% elongation. Additionally, interconnect deformation was compared to finite element analysis (FEA) simulations to show that FEA can be used to accurately model the deformation of low-strain printed interconnects. Overall, this paper demonstrates a simple and affordable route toward stretchable electrical interconnects.