AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Electrically Conducting, Near Bulk Density, Micrometer Thick Metal Coatings through Room Temperature Supersonic Aerosol Deposition
YENSIL PARK, Souvik Ghosh, Christopher Hogan Jr., University of Minnesota
Abstract Number: 57 Working Group: Nanoparticles and Materials Synthesis
Abstract Electrical conducting coatings and thin films are commonly needed in organic solar cells and organic light emitting diodes (OLEDs) to ensure proper electrical conduction. Recent advances in additive manufacturing have led to room temperature production routes for such organic devices. However, conducting layers are typically made of metal; aside from near-room temperature liquid metals (which are expensive and often highly toxic), metal coating production requires high temperature or high vacuum techniques incompatible with most organic components. Supersonic aerosol deposition is a reduced temperature (room temperature or lower) modestly high pressure (5 Torr or higher) process where submicrometer to micrometer scale particles are passed through a converging-diverging nozzle and deposited inertially onto a substrate. Here, we demonstrate that this process can be used to produce Sn coatings from commercial Sn powder which are electrically conducting and of near bulk density. The mechanism of coating formation is the plastic deformation of particles upon impact. We show that the size distribution of the depositing powder strongly affects the deposition; simulations reveal that there is a particle size of maximum impaction velocity (near 500 m s-1 at 1-2 micrometers for the system utilized). Smaller particles deposit but do not appear to plastically deform, leading to poor substrate adhesion. Meanwhile, larger particles, appear to bounce from substrate and ablate away poorly adhered material.