Fully-printed vertical interconnections with tapered contact holes formed by vapor-annealing technique

In this paper, we present fully-printed vertical interconnections by reverse offset printing. In contact hole patterning, a vapor annealing of dielectric ink layers was used to add a taper structure on the edge of the dielectric layers. The technique involved rewetting of the layer by solvent adsorption from the vapor and subsequent morphological change according to Laplace pressure. It was also confirmed that the transfer of subsequent conductive layers was much reliable when the taper structure was added. With the optimization of silicone blanket specifications, a fully printed contact chain with the hole size of 25 μm was successfully demonstrated.