Abstract: A high-density circuit has a plurality of conductors formed in grooves in a ceramic substrate, the conductors having a height less than that of the walls of the grooves. The substrate is embossed with a pattern of grooves corresponding to the grooves in an electroform made from a master tool. The same master tool is used to form a stencil which mates with the grooved substrate. A cermet paste is pushed through the stencil, so as to fill the bottom region of the grooves, and the stencil is then removed, leaving only the paste at the bottom of the grooves. The substrate is then fired, causing the substrate to harden, and causing the cermet to become conductive and to become firmly bonded to the substrate. Because the stencil and the substrate are made from the same, or replications of the same, master tool, the cermet paste can be laid down with great precision, thus enhancing the quality of the product, and reducing the cost of its manufacture.