Glass-ceramics for electronic packaging

Abstract From the Canadian patent

This invention relates to the production of glass-ceramic materials particularly suitable for use as substrates in integrated circuit packaging. The inventive glass-ceramics can be prepared from thermally crystallizable glass capable of being concurrently sintered and crystallized in situ at temperatures between about 850°-1000°C to bodies exhibiting dielectric constants less than about 6 linear coeffi-, cients of thermal expansion between about 12-60X10-7/°C and containing cordierite solid solution as essentially the sole crystal phase. The glass-ceramics are essentially free from Li2O and Na2O and consist essentially expressed in terms of weight percent on the oxide basis of 10-25% MgO + …