Patent ID: 7170012
Filing Date: 2007-01-30
Classification: H05K

Abstract:
1. An electronic apparatus comprising: a multilayer circuit board on which semiconductor devices are directly bonded, wherein said multilayer circuit board comprises: a laminate of at least one insulating layer and a plurality of wiring layers separated from one another by an insulating layer, wherein at least one of the wiring layers in the multilayer circuit board is formed by a composite material comprising a first metal layer and a second metal layer formed on one or both sides of the first metal layer, the first metal layer having a smaller coefficient of thermal expansion than that of the second metal layer, the second metal layer having a higher electric conductivity than that of the first metal layer, wherein the insulating layer which is in contact with the second metal layer has a blind via-hole whose bottom portion is formed by a surface of the second metal layer, wherein the composite material and the wiring layers are in layer-to-layer interconnection with one another through a layer-to-layer interconnection portion which is in contact with the second metal layer formed in the blind via-hole.