Abstract: A hybrid assembly having improved cross talk characteristics includes a substrate having an upper surface. Conductive paths on the upper surface are provided for conducting high frequency signals. Regular polygons made of an electromagnetic band gap (EBG) material having slow wave characteristics are deposited on the upper surface and form a lattice for tessellating the upper surface. Each of the polygons has a periphery. The polygons are separated along their periphery from adjacent polygons by an interspace and are covered with an insulating material. Second polygons, also made of an electromagnetic band gap material, are deposited over the insulating material. Semiconductor structures are mounted over the second polygons. The semiconductor structures have a plurality of electrical contacts with the conductive paths. The regular polygons can be hexagons, triangles, octagons or any other combination that forms a lattice and can be printed onto the substrate.