Patent ID: 6831357
Filing Date: 2004-12-14
Classification: H01L,H05K

Abstract:
A circuit substrate device including a circuit unit having one or more wiring layers each having a pattern conductor formed by a thin film technique, and an insulating layer, said circuit unit also having electrically conductive lands formed on an uppermost layer of said wiring layers(s), said lands acting as an interface for said circuit unit, anda multi-layer wiring substrate including a connecting portion exposed from a major surface thereof; wherein said circuit unit contains one or more passive electrical elements and is formed over a release layer on a dummy substrate, having a flattened out surface, thereby having a minimal amount of warping in the direction of thickness, and wherein said circuit unit is connected to the major surface of said multi-layer wiring substrate so that said lands connect to said connecting portion of said multi-layer wiring substrate; said dummy substrate and said release layer being removed by peeling at said release layer to give a structure comprised of said circuit unit formed on the major surface of said multi-layer wiring substrate.