Experimental and simulation investigations on the morphology of aerosol jet printed polymer traces under in-situ UV and thermal curing conditions

With the benefits of fast curing under ambient conditions, space, energy efficiency, and high resolution patterns, ultraviolet (UV) curable resin has great potential in the domain of Aerosol-jet (AJ) printing (one form of direct write printing methods). However, the geometric and performance deviations between design and fabrication are commonly observed. The in-situ curing mechanism of UV curable microdroplets is found to significantly influence the fabrication resolution in both lateral and depth dimensions which are critical for fabricating complex structures in AJ printing. In this work, we developed a predictive model to reflect the in-situ thermal-photopolymerization process of microdroplets in AJ printing through the finite element analysis (FEA) method and analyzed the influence of substrate temperature on the printing morphology, the distribution of velocity, monomer concentration as well as degree of curing (DOC) in the microdroplets through the combination of experiment and simulation and realized the correlation between the microdroplet curing process and the printing geometry. The simulation results obtained by the prediction model are consistent with the variation trend of printed ink streams under the influence of substrate temperature, and the errors in the direction of line width are within the range of 2.3%−7.9%. It may have important application value in realizing morphology control and improving fabrication controllability in AJ printing.