Monolithic, buried-substrate, ceramic multiple capacitors isolated, one

Abstract

A monolithic, buried-substrate, ceramic multiple capacitor is laid up as multiple capacitors that are isolated, one to the next, by a dual-dielectric-constant, three-layer-laminate, isolation layer. Each isolation layer has and presents (i) an innermost layer of a low dielectric constant (low K) material, located between (ii) outer laminate layers of a high dielectric constant (high K) material. By such construction negative effects of the physio-chemical reaction (i) occurring at the boundary between the high-K and low-K layers, (ii) contaminating the high-K dielectric and lowering its K, and (iii) undesirably serving both to lower the capacitance of any (buried substrate) capacitor that makes use of the ('contaminated') high-K dielectric while increasing capacitor leakage current, are mitigated or avoided. This occurs because the physio-chemical reaction zone, or band, located between the high-K dielectric layers (from which each buried-substrate capacitor is formed) and the low-K dielectric isolation layer (between successive capacitors) is moved slightly away from the region of the capacitor itself. Moreover, the ceramic multiple capacitor is strongly and stably fused together in its several layers, which different layers of different dielectric constant have different thermal coefficients of expansion, because the outer (high-K) laminate layers of the isolation layer are preferably of intermediary thickness between the innermost (low-K) layer and the (high-K) dielectric layers of the bordering buried-substrate capacitors.