| abstract |
The present invention relates to the manufacture of new items and to a method of manufacturing the same in a broad sense, in some form of multilayer co-fired ceramic-on-metal circuit boards. The present invention particularly relates to various compositions of glass-ceramics of MgO-B 2 O 3 -BiO 2 based and suitable glass-ceramics and suitable fillers for use in the manufacture of multilayer-co-fired ceramic-on-metal-circuit boards. Concerning the composition, the co-fired multilayer ceramic here exhibits a coefficient of thermal expansion and desirable electrical properties close to that of the co-fired metal base, although the composition may have other uses.n n n The present invention also relates to a method of manufacturing the circuit board 10 using a glass bonding layer having a coefficient of thermal expansion equal to that of the metal base 12.n n n The glass bonding layer has a softening point below the softening point of the glass of the multilayer ceramic 20 on its surface, so that the glass of the bonding layer flows and bonds to the metal, while the side water side of the multilayer ceramic is minimized. |