Combinations of materials to minimize esr and maximize esr stability of surface mount valve-metal capacitors after exposure to heat and/or humidity

Abstract

Single element and/or multiple element valve-metal, solid-electrolyte, surface-mount capacitors are manufactured using one or more materials taken from the following three categories of materials: graphitic carbon, highly-conductive metal-powder-filled paint, and metallic terminals. The resulting capacitors have lower equivalent series resistance (ESR) at 100 kHz than do similar capacitors manufactured with conventional materials and with conventional techniques. Moreover, not only do these devices possess lower “as-manufactured” ESR, but also their ESR is substantially more stable (less increase in ESR) when these devices are exposed to IR reflow temperatures, high humidity, thermal shock, 1000 hours at 150° C., and 1000 hours at 175° C.