Multi-physics simulation of metal printing at micro/nanoscale using meniscus-confined electrodeposition: Effect of nozzle speed and diameter

Meniscus-confined electrodeposition (MCED) is a solution-based, room temperature process for 3D printing of metals at micro/nanoscale. In this process, a meniscus (liquid bridge or capillary) between a nozzle and a substrate governs the localized electrodeposition process, which involves multiple physics of electrodeposition, fluid dynamics, mass, and heat transfer. We have developed a multiphysics finite element (FE) model to investigate the effects of nozzle speed (vN) and nozzle diameter (D0) in the MCED process. The simulation results are validated with experimental data. Based on theoretical approach and experimental observation, the diameter of the deposited wire is in the range of 0.5–0.9 times of the nozzle diameter. The applicable range for vN for various nozzle diameters is computed. The results showed that the contribution of migration flux to total flux remains nearly constant (∼50%) for all values of pipette diameter in the range examined (100 nm–5 μm), whereas the contribution of diffusion and evaporation fluxes to total flux increase and decrease with the increasing pipette diameter, respectively. Results of this multiphysics study can be used to guide the experiment for optimal process conditions.