Patent ID: 7138294
Filing Date: 2006-11-21
Classification: H01L,H05K

Abstract:
1. A method for producing a circuit substrate device comprising: a circuit unit forming step of forming a circuit unit over a dummy substrate with a release layer between the circuit unit and the dummy substrate, said 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 a land unit, on an uppermost layer of said wiring layer(s), said land unit connecting to said pattern conductor; a substrate forming step of forming a multi-layer wiring substrate including a connecting portion exposed from a major surface thereof; a bonding step of connecting said circuit unit to the major surface of said multi-layer wiring substrate for connecting said land unit to said connecting portion; and a removing step of removing said dummy substrate and said release layer by releasing said release layer from said circuit unit.