The method of co-extrusion of dissimilar materials has been developed at the PARC, a Xerox Company, to successfully produce high aspect ratio structures for solar cell gridlines. In the solar application, the process is stable and repeatable, and a fully integrated tool has been developed that is now being demonstrated at a customer site. The co-extrusion process is capable of non-contact, direct deposition of features as small as 1 – 10 um with aspect ratios in the range of 1:1 to 30:1. Alternating fluids are co-extruded to form a fine vertically interdigitated lamina structure. The relative thickness, width, and length of the deposited features can be varied by altering the printhead geometry and printing process conditions.