Process Recipe and Functional Circuitry Performance on Aerosol Jet Printed Water-Based Silver Ink

Abstract

The demand for compact, lightweight, and stretchable printed electric circuits has increased with the advancement of flexible printing technology in electronics. The viability of environmentally friendly water-based inks with low-impact waste requires the development of process recipes for component attachment on flexible substrates. The focus of this paper is on demonstrating a comprehensive study of process parameters and component attachment on the aerosol jet printer (AJP) platform, utilizing water-based silver nanoparticle ink. The investigation covers printing parameters, including ultrasonic atomizer mass flow control (UAMFC), sheath flow control (SMFC), stage speed, multiple passes, and sintering analysis (time and temperature). The evaluation of print quality is conducted using white light interferometry (WLI) and optical microscopy images. The cross-sectional area (CSA) of printed lines is computed by integrating the bell-shaped CSA obtained from the WLI test. Electrical and mechanical properties are quantified in terms of resistivity and shear load to failure. Optimized parameters from the printing and sintering process are employed to print traces, and various components are attached using electrically conductive adhesive (ECA). The impact of sustainable ink and ECA on passive components is analyzed by comparing their performance before and after attachment. Components within an acceptable range of the rated value are in proper functioning order, contributing to the advancement of flexible and sustainable electronics. Finally, a practical differentiator circuit has been used to demonstrate the functionally working circuitry and compared the output with the simulated one.