Patent ID: 8929090
Filing Date: 2015-01-06
Classification: H01L,H05K,Y10T

Abstract:
1. A functional element built-in substrate including, a functional element provided with an electrode terminal on one surface side of the functional element, and a wiring substrate including a laminated structure in which the functional element is embedded so that the electrode terminal of the functional element faces the front surface side of the structure, and which is formed at least in a side surface region of the functional element by laminating a plurality of wiring insulating layers each including a wiring, wherein the electrode terminal and the back surface side of the wiring substrate are electrically connected through the wiring of the laminated structure, and wherein, in a pair of the wiring insulating layers included in the laminated structure and that are in contact with each other, the cross-sectional shape of the wiring in each of the wiring insulating layers, which cross-sectional shape is taken along the plane perpendicular to the extension direction of the wiring, has a relationship that the cross-sectional area of the wiring in the back surface side wiring insulating layer is larger than the cross-sectional area of the wiring in the front surface side wiring insulating layer, wherein, in any pair of the wiring insulating layers included in the laminated structure and that are in contact with each other, the cross-sectional shape of the wiring in each of the wiring insulating layers has a relationship that the cross-sectional area of the wiring in the back surface side wiring insulating layer is larger than the cross-sectional area of the wiring in the front surface side wiring insulating layer.