Process considerations for Aerosol-Jet printing of ultra fine features

In recent years, Aerosol-Jet (AJ) printing has become an increasingly popular technology applied in research ranging from the biomedical field to military applications to printed semiconductors. Extensive efforts have been made to understand the influence of process parameters and the underlying physical principles. Nevertheless, little attention has been paid to the optimization of ultra-small and highly precise printed features. Pushing the printer to its limits and manufacturing structures as small as tens of microns with a micrometer accuracy poses significant challenges, because effects that can be ignored for printing large features play a crucial role. This study demonstrates how the printing speed quickly causes intolerable distortions. In contrast to large-feature printing, the printing speed cannot be used as a free parameter to set the print thickness. We will discuss the non-constant printing behavior induced by the divert/boost shutter and present shutter on the fly as a solution to many problems, but only if the subroutine code is optimized. The modifications made to the code are disclosed in this paper for the first time. Knowing that printing precise features often results in a high print thickness, we will briefly discuss the issue of cracks caused by the drying of thick nanoparticle films. Altogether, this paper presents a range of important considerations for AJ printing ultra-fine features and an interesting insight into the particularities of operating the printer at its limits.