Additive manufacturing of robust, nonplanar electrical interconnects

Optomecrsquo;s proposed innovation is a direct-write additive manufacturing process, creating 25um electrical interconnects that can accommodate 3D steps and are terminated in a wire bond pad.nbsp; These printed interconnects will minimize packaging space by replacing traditional wire bonds with conformal fan-out electrodes.nbsp; This additive manufacturing proposal ldquo;is a science enabling technology for the next strategic-class of astrophysics missions,rdquo; as stated in scope description of solicitation S12.06. Improving the packaging for large-format multishutter arrays is a goal relevant to several NASA missions, including the Large UV/Optical/IR Surveyor (LUVOIR) and the Habitable Exoplanet Observatory (HabEx) missions.Optomecrsquo;s innovation uses metal nanoparticle suspensions or ldquo;inksrdquo; to create pad and trace patterns, and these patterns are functionalized by sintering the metal nanoparticles at low temperatures or with a laser to make electrically conductive conformal interconnects. The Aerosol Jetreg; technology creates a high velocity stream of tightly collimated droplets, which means that liquid inks can easily be jetted in precise patterns.nbsp; Tilting the jetting head relative to the flat substrate gives direct vision of both horizontal surfaces and vertical sidewalls, enabling interconnect printing over steps up to 1.5mm high and beyond.nbsp; The tight collimation of the Aerosol Jet stream also means that Optomec can create very fine features, 25um size and smaller.nbsp;This Phase 1 NASA project will deliver test analysis and samples focusing on two important performance metrics for these printed interconnects: electrical isolation and wire bond reliability.nbsp; Overspray of ink droplets outside the central printed lines can cause electrical shorting, and this will be measured and controlled.nbsp; Finally, we will test the strength and reliability of bonds made to conformal printed pads.