Influence of 3D printing strategy on high-frequency properties of electronics

Common printed circuit boards consist of several layers, whose contacts to each other represent a significant resistance in data transmission. Components are usually arranged on boards only on top or at the bottom. Additive manufacturing processes now makes it possible to route the vias without the layer-based restirctions in the design spacs. In addition, capacitors, coils, heat sinks and shielding can be printed directly and other components can be used.

Multijet modeling printing (MJM) processes can already be used to print circuit boards and simple components with photopolymers and suspensions containing conductive nanoparticles. Printing electrical conductors allows higher power density by eliminating points of high impedance and realizing shorter transmission paths. If additional mechanical tasks are added to the electronic printed component due to the design freedom, further advantages appear.

In the state of the art, this 3D printing process is done layer-by-layer, meaning that one layer is processed after the next layer. Due to the wetting process, this results in a rough surface at the boundary of conductive to insulating material, which is detrimental to the high-frequency properties. CFD simulation is used to investigate the influence of the printing strategy, for example printing in blocks instead of individual layers, on the roughness of the interface - and therefore the high-frequency properties. Initial results promise significantly lower losses in the electrical lines.