Interaction of Process-Parameters and Realized Properties of Additively Printed Z-axis Interconnects in Multilayer Circuits

A number of processes for additive printed electronics have emerged including aerosol-jet printing, inkjet printing, dispense-on-demand printing, screen-printing, gravure printing amongst others. Additive printed technologies allow for design of manufacture of electronics in exceedingly small lot-sizes owing to the ability to print parts on demand. Technologies such as aerosol-jet, ink-jet printing, and dispense-on-demand printing allow for manufacture of non-planar components without the need for planar build-up often used in traditional methods presently used for electronics design and fabrication. In this paper, the correlation of the mechanical properties of aerosol jet printed multi-layer substrates and z-axis interconnects with process parameters has been studied. The print process-parameters of the aerosol-jet printed traces have been correlated to the performance and properties of the printed lines. The shear load to failure and resistivity of the printed line have been studied to quantify the performance of the printed lines. Process parameters studied include sheath flow rate, ink flow rate, stage speed, standoff height, chiller temperature, platen temperature. A better understanding of the effect of each process parameter in the printed lines will allow users to select appropriate process parameters for design functional performance. In addition, the development of process-property relationships will provide visibility into the critical parameters, which require an added level of attention for process-control. Process parameter drift over a long production run may be important for a high-volume production environment. The effect on the print process may be in the form of line consistency, and resistance both of which have been quantified in this study through the quantification of process-capability for z-axis interconnects. Data is presented on 2-layer and 5-layer substrates.