Design space characterization of printable photopolymer and silver inks for model-driven inkjet pattern accuracy optimization of printed circuitry

Purpose This study aims to investigate methodologies governing design space designation for enhancement of inkjet print accuracy through regression-driven optimization of patterning instruction. Inkjet design optimization reflects a multivariable parameter space encompassing ink formulation, extrusion parameter modification and extrudate process variation, whereby optimization compensates for errant extrudate flow following contact with substrate surfaces. Design/methodology/approach Ultraviolet (UV)-curable dielectric photopolymer (DI) and thermally reactive silver (Ag) inks were inkjet printed for characterization of voxel and trace extrudate patterning accuracy as deposited natively, or corrected, through regression-derived pattern error compensation prior to termination of microstructure development. Findings This manuscript presents voxel (DI 64.25 → 8.74% | Ag 21.21→ 2.59%, 250 μm) and trace (DI 67.46 → 3.09% | Ag 26.40 → 0.35%, 250 μm) overprint error reduction interpolated via power law regression. Inkjet patterning optimization of Ag films (9.75 Ohm/sq | 18.13 MS/m) coupled with in situ UV-irradiation optimization of DI photopolymer support (0.20 W/mm2) guides the encasement of Ag traces within photopolymer packaging for isolated stacking of conductive circuits. Analysis of variance (ANOVA) quantified the significance of the relatedness of the extrusion parameter and extrudate process modification with extrudate pattern dimensionality within a 95% confidence interval. Originality This study demonstrates methodologies for the improvement of inkjet patterning accuracy regarding circuit design optimization, with the intent to advance inkjet-printed circuit prototyping toward standardization requirements sufficient for scalable manufacturing.