| abstract |
A circuit board assembly (30) that makes use of a low-temperaturenco-fired ceramic (LTCC) substrate (10), and a process for producing thenassembly (30). The substrate (10) contains at least first and second regionsn(32,34) formed by a plurality of first ceramic layers (36) and at least one secondnceramic layer (38), respectively, that are superimposed and bonded to eachnother. Conductor lines (22) are present on at least some of the first ceramicnlayers (36) so as to be between adjacent pairs of the layers (36). Electrically-conductivenvias (16) electrically interconnect the conductor lines (22) onndifferent first ceramic layers (36), and a surface-mount IC device (12) isnmounted to the substrate (10). The first ceramic layers (36) are formed ofnelectrically-nonconductive materials, while the one or more second ceramicnlayers (38) contain thermally-conductive particles dispersed in a matrix ofnelectrically-nonconductive materials, such that the one or more second ceramicnlayers (38) are more thermally conductive than the first ceramic layers (36). |