Aerosol Jet printing on rapid prototyping materials for fine pitch electronic applications

Printing technologies allow the production of fine pitch electronic applications supporting further miniaturization of mechatronic systems. Aerosol Jet^® is an innovative non-contact and maskless printing process for fine structures below 50 μm with the possibility to process a wide variety of inks, including nanoparticle inks on different substrate materials. The large viscosity range of processible inks (0.7-2,500 cP), a flexible stand-off between substrate and nozzle (1 to 5 mm) as well as the tightly focused aerosol stream for a variable line width leads to advantages compared to other printing methods like ink-jet. The concern of this research work is to qualify the Aerosol Jet technique to manufacture prototypes for MID (Molded Interconnect Devices). Therefore, three different inks are examined for their suitability concerning adhesiveness, conductivity and wetting characteristics on four different substrates. The research activities focus on stereolithography materials (resins) with high heat resistance suitable for soldering processes. The materials are analyzed with reference to thermoplastic substrates. The experiments are performed on untreated and plasma activated substrates. Besides the ink/substrate combination, optimizing the process parameters (aerosol stream, process velocity, and number of printed layers) have shown crucial effect.