| abstract |
The substrate is formed by a stack of sheets of dielectric material (10), at least some of which carry conductive patterns (21-24); this substrate has conductive openings (31, 32) to ensure the connection at the terminals of the component (1), with at least one internal layer provided with conductive tracks (24) ensuring the interconnection from layer to layer and with the emergences according to a pre-established scheme.n n n According to the invention, the composition of the dielectric material comprises 92 to 98% of alumina, preferably 96%, and a melting agent based on magnesia titanate making it possible to lower the maximum baking temperature to approximately 1400 ° C .; the conductive patterns are made of a metal which cannot be oxidized and which cannot be melted at high temperature, such as palladium or a silver-palladium alloy.n n n The properties of the substrate thus obtained are comparable to those of 99.9% ultra-pure alumina.n n n The invention also applies to multi-level chip carriers produced from this material. |