Laser-induced forward transfer of silver nanopaste for microwave interconnects

We explore the effect of variations in laser fluence and donor-receiver substrate distance on the laser-induced forward transfer technique for high viscosity Ag nanopaste. By transferring 50 mu m x 50 mu m voxels with thicknesses between 0.8 and 8.7 mu m at different laser fluences, we are able to systematically determine a thickness-fluence regime for successful transfer that widens with increasing voxel thickness. We use these results to study congruent transfer of square voxels with lateral dimensions spanning 2 orders of magnitude: 5 mu m x 5 mu m, 50 mu m x 50 mu m, and 500 mu m x 500 mu m. We conclude by linking a multitude of voxels together in 1 mm and 3 mm lines to fabricate the center conductor in coplanar waveguides (CPWs) with relatively low loss up to 10 GHz. (C) 2015 Elsevier B.V. All rights reserved.