Circuit device and manufacturing method thereof

摘要

A circuit device including a multilayer wiring structure having an improved heat radiation performance, and a manufacturing method thereof is provided. A circuit device of the invention includes a first wiring layer and a second wiring layer laminated while interposing a first insulating layer. The first wiring layer is connected to the second wiring layer in a desired position through a connecting portion formed so as to penetrate the first insulating layer. The connecting portion includes a first connecting portion protruding in a thickness direction from the first wiring layer, and a second connecting portion protruding in the thickness direction from the second wiring layer. The first connecting portion and the second connecting portion contact each other at an intermediate portion in the thickness direction of the insulating layer.