Printing conformal electronics on 3D structures with Aerosol Jet technology

Fabrication of 3D mechanical structures is sometimes achieved by layer-wise printing of inks and resins in conjunction with treatments such as photonic curing and laser sintering. The non-treated material is typically dissolved leaving the final 3D part. Such techniques are generally limited to a single material which makes it difficult to integrate high resolution, conformal electronics over part surfaces. In this paper, we demonstrate a novel, non-contact technique for printing conformal circuits called Aerosol Jet printing. This technique creates a collimated jet of aerosol droplets that extend 2-5 mm from the nozzle to the target. The deposited features can be as small as 10 microns or as large as a centimeter wide. A variety of materials can be printed such as metal nanoparticle inks, polymers, adhesives, ceramics, and bio-active matter. The print head direction and XYZ positioning is controlled by CAD/CAM software which allows conformal printing onto 3D substrates having a high level of surface topography. For example, metallic traces can be printed into 3D shapes such as trenches and via holes, as well as onto sidewalls and convex and concave surfaces. We discuss the fabrication of a conformal phase array antenna, embedded circuitry and sensors, and electronic packaging.