Abstract
The earlier generation of additive printable inks was based on volatile organic solvent carrier fluids. Increased awareness of the environmental impact of electronic waste has resulted in the emergence of environmentally friendly water-based inks with low-impact waste. The repairability of additively printed circuits can be used to reduce electronic waste and enable life extensions of deployed electronics through repair and replacement. However, the repairability potential, processes, and impact on reliability are relatively unexplored for new sustainable materials. This study consists of a thorough study of component attachment and the reparability of the components on performance and reliability. Repair procedures have been pursued on circuits printed with sustainable conductive ink on an aerosol jet printer (AJP). Adhesives are printed on the pads at the location where the component is to be attached using a direct-write technique that can print highly viscous materials such as ECA. This procedure entails attaching a component to a flexible printed circuit, measuring the output response, removing the attached component from the circuit, replacing it with a new component of the same rated value, measuring the output again, and comparing it to the prior output and the simulated output. Furthermore, the mechanical strength of the attached components is characterized in terms of shear load to failure. The force required to remove the attached component using a metal tip before and after the repair is compared for each of the passive components. Finally, a functional differentiator circuit is used to validate the findings.
