An electronic component structure is proposed, wherein an interposer thin film capacitor structure is employed between an active electronic component and a multilayer circuit card. A method for making the interposer thin film capacitor is also proposed. In order to eliminate fatal electrical shorts in the overlying thin film regions that arise from pits, voids, or undulations on the substrate surface, a thick first metal layer, on the order of 0.5-10 .mu.m thick, is deposited on the substrate upon which the remaining thin films, including a dielectric film and second metal layer, are then applied. The first metal layer includes of Pt or other electrode metal, or a combination of Pt, Cr, and Cu metals, and a diffusion barrier layer. Additional Ti layers may be employed for adhesion enhancement. The thickness of the first metal layers are approximately: 200 A for the Cr layer; 0.5-10 .mu.m for the Cu layer; 1000 A-5000 A for the diffusion barrier; and 100 A-2500 A for a Pt layer.