Semiconductor device

A semiconductor device comprising:

• a first substrate having a first front surface and a first back surface opposite to the first front surface;
• a second substrate having a second front surface and a second back surface opposite to the second front surface and being mounted over the first substrate with the first front surface of the first substrate facing the second back surface;
• a first semiconductor component mounted over the second front surface of the second substrate and coupled with a plurality of first signal transmission paths;
• and
• a second semiconductor component mounted over the second front surface of the second substrate and electrically coupled with the first semiconductor component through a plurality of second signal transmission paths,
• the first signal transmission paths each comprising:
• a first coupling part to couple the first semiconductor component and the second substrate electrically;
• a second coupling part to couple the second substrate and the first substrate;
• a first external terminal formed on the first back surface of the first substrate;
• a first transmission part located in the second substrate to couple the first coupling part and the second coupling part electrically;
• and
• a second transmission part located in the first substrate to couple the second coupling part and the first external terminal electrically,
• wherein each of the first signal transmission paths is coupled with a first circuit part having one edge coupled with a first branching part located midway in the second transmission part and the other edge coupled with a first capacitative element,
• wherein the second substrate comprises a first core insulating layer, a plurality of first through hole wirings penetrating the first core insulating layer in the thickness direction, a first wiring layer lying between the first core insulating layer and the second front surface, and a second wiring layer lying between the first core insulating layer and the second back surface,
• wherein the second signal transmission paths are not formed in the first through hole wirings and the second wiring layer, and
• wherein a first electrode configuring the first capacitative element of the first circuit part is formed in the second wiring layer of the second substrate.