Conductive silver low temperature cofired metallic green tape

摘要

The present invention provides a thermally conductive material which can be used as a heat sink in a multi-chip module or multilayer circuit structure. The material is formed by firing a composition including a solids portion comprising from about 1% to about 30% by weight glass and from about 70% to about 98% by weight silver. The glass comprises in weight percent from about 5% to about 60% B.sub.2 O.sub.3, from about 30% to about 90% SiO.sub.2, up to 10% Li.sub.2 O, up to 10% Na. sub.2 O, up to 10% K.sub.2 O and up to 10% Al.sub.2 O.sub.3. The material may be formed using a second glass selected from the group comprising of (i) a glass comprising in weight percent from about 10% to about 60% CaO, from about 5% to about 55% B.sub.2 O.sub.3 and from about 5% to about 55% SiO.sub.2 ; and (ii) a glass comprising in weight percent from about 35% to about 70% SiO.sub.2, from about 20% to about 45% Al.sub.2 O.sub.3, from about 0% to about 8% BaO and from about 5% to about 30% MgO.