Abstract: Sealing and stress relief are provided to a low-fracture strength glass-ceramic substrate. Hermeticity is addressed through the use of capture pads in alignment with vias and through polymer overlays with interconnection between the underlying via or pad metallurgy and the device, chip, wire or pin bonded to the surface of the layer. Multilevel structures are taught along with a self-aligned sealing and wiring process.

Abstract: A method of fabricating a multilayer ceramic substrate with an internal conductive metallurgy circuit network, wherein additional green sheet material is added to the stack of ceramic green sheets during assembly to areas of the substrate outside of the conductive metallurgy to compensate for the volume of conductive metal paste to thereby eliminate or minimize substrate distortion during the sintering operation. An unsintered intermediate green ceramic substrate made up of green ceramic sheets with via holes and conductive metal lines on the surface which collectively form the circuit network where the improvement is additional green ceramic material in the substrate in areas outside of the conductive metallurgy network to compensate for the additional volume of material of the conductive metal which additional material provides a more uniform ceramic material density through the substrate.

Abstract: The obtention of enhanced planarity and dimensional integrity of sintered glass-ceramic substrates containing multi-level distribution of conductor patterns (e.g. copper) by a two stage firing of the green sheets, first between the anneal and softening points of crystallizable glass particles, interrupting the firing, superimposing selected light weights on the substrates, and heating through the coalescing temperatures to the crystallization of the glass.

Abstract: A method of achieving uniform shrinkage of a laminated green ceramic substrate during sintering wherein the substrate is placed on a flat, relatively thick plate of refractory material such as molybdenum, tantalum or tungsten or alloys thereof with the flat plate provided with a thin surface coating layer of a ceramic material, and heating the substrate to a sintering temperature and maintaining the temperature for a time sufficient to sinter the substrate.A setter plate for supporting a planar green ceramic substrate during the sintering operation, the setter plate is made of a refractory material and provided with a thin ceramic coating at least on the top surface.