Wiring substrate

摘要

A wiring substrate includes a first wiring substrate, a first insulation layer stacked on the first wiring layer, and second and third insulation layers sequentially stacked on the first insulation layer. An electronic component is mounted on the first insulation layer in a cavity extending through the second and third insulation layers. The cavity is filled with a fourth insulation layer that entirely covers an upper surface of the third insulation layer and covers the electronic component. A second wiring layer is incorporated in the second and third insulation layers and electrically connected to the first wiring layer. The second wiring layer is electrically connected to a third wiring layer, which is stacked on the fourth insulation layer, by a first via wiring extending through the second and third insulation layers.

主权项

1. A wiring substrate comprising:
a first wiring layer; a first insulation layer stacked on the first wiring layer; a plurality of insulation layers including a second insulation layer, which is stacked on an upper surface of the first insulation layer, and a third insulation layer, which is stacked on an upper surface of the second insulation layer; a cavity that extends through the plurality of insulation layers and partially exposes the upper surface of the first insulation layer; an electronic component mounted on the first insulation layer exposed in the cavity; a fourth insulation layer that entirely covers an upper surface of an uppermost one of the plurality of insulation layers and covers the electronic component, wherein the cavity is filled with the fourth insulation layer; a second wiring layer electrically connected to the first wiring layer, incorporated in the plurality of insulation layers, and covered by the uppermost one of the plurality of insulation layers, wherein the second wiring layer is formed on the upper surface of the second insulation layer; a first via wiring formed by a single via wiring, wherein the first via wiring extends continuously through the uppermost one of the plurality of insulation layers and the fourth insulation layer from an upper surface of the fourth insulation layer to an upper surface of the second wiring layer; and a third wiring layer stacked on the upper surface of the fourth insulation layer and electrically connected to the second wiring layer by the first via wiring, wherein the upper surface of the uppermost one of the plurality of insulation layers is free from a wiring layer.