Semiconductor device and method of manufacturing the same

A semiconductor device comprising:

• a first semiconductor substrate having a first front surface and a first back surface opposite the first front surface;
• a first wiring layer formed on the first front surface of the first semiconductor substrate, the first wiring layer comprising a first electrode pad and a first inductor electrically connected with each other;
• a second wiring layer formed on the first wiring layer, the second wiring layer comprising a second electrode pad and a second inductor electrically connected with each other and a third electrode pad electrically connected with the first electrode pad, the first inductor and the second inductor facing each other;
• a second semiconductor substrate formed on the second wiring layer, the second semiconductor substrate having a second front surface and a second back surface opposite to the second front surface, the second wiring layer being formed on the second front surface of the second semiconductor substrate;
• a first conductive portion extending from the second back surface of the second semiconductor substrate to the third electrode pad in the second wiring layer such that the first conductive portion penetrates through the second semiconductor substrate and the second wiring layer;
• and
• a second conductive portion extending from the second back surface of the second semiconductor substrate to the second electrode pad of the second wiring layer such that the second conductive portion penetrates through the second semiconductor substrate to the second wiring layer,
• wherein the second conductive portion directly contacts the second semiconductor substrate.

A manufacturing method of a semiconductor device, the manufacturing method comprising:

• preparing a first semiconductor chip comprising a first semiconductor substrate and a first wiring layer formed on the first semiconductor substrate, the first wiring layer comprising a first inductor and a first electrode pad electrically connected with each other;
• preparing a second semiconductor chip comprising a second semiconductor substrate and a second wiring layer formed on the second semiconductor substrate, the second wiring layer comprising a second inductor and a second electrode pad electrically connected with each other;
• laminating the first wiring layer and the second wiring layer with each other such that the first inductor and the second inductor face with each other;
• and
• forming a first conductive portion and a second conductive portion,
• wherein forming the first conductive portion includes:
• forming a first opening in the second semiconductor substrate, the second wiring layer, and the first wiring layer such that the first opening reaches the first electrode pad from a back surface of the second semiconductor substrate;
• burying the first opening with a first conductive film,
• wherein forming the second conductive portion includes:
• forming a second opening in the second semiconductor substrate and the second wiring layer such that the second opening reaches the second electrode pad from the back surface of the second semiconductor substrate;
• burying the second opening with a second conductive film, and
• wherein the second conductive portion directly contacts the second semiconductor substrate.