Semiconductor device
A semiconductor device includes a structure in which a semiconductor element (chip) is mounted in a cavity formed in a wiring board with an adhesive interposed between the chip and a bottom surface of the cavity, and electrode terminals of the chip are connected via wires to wiring portions formed on the board around the cavity. The chip is mounted in close contact with a side wall of the cavity, the side wall being near a region where a wiring for higher frequency compared with other wirings within the wiring portion is formed. A recessed portion is provided in a region of the bottom surface of the cavity, and a thermal via extending from the bottom surface of the recessed to the outside of the board is provided, the region being near a portion where the chip is in close contact.
1. A semiconductor device, comprising:
a wiring board including a first surface, a second surface opposite to the first surface, a cavity formed therein on the first surface side and a wiring portion formed thereon around the cavity;
a semiconductor element mounted on a bottom surface of the cavity via an adhesive, the semiconductor element having an electrode terminal connected via a wire to the wiring portion of the wiring board; and
a heat-radiating structure,
wherein the semiconductor element is mounted in close contact with a side wall of the cavity, the side wall being near a region where a wiring for higher frequency compared with other wirings within the wiring portion is formed, and
the heat-radiating structure is provided in a region of the bottom surface of the cavity, in which a recessed portion filled with the adhesive is provided, the region being near a portion where the semiconductor element is in close contact with the side wall, the heat-radiating structure being formed through the writing board in a direction from the bottom surface of the recessed portion and the bottom surface of the cavity other than the bottom surface of the recessed portion toward the second surface.
2. The semiconductor device according to claim 1 , wherein the heat-radiating structure includes a first heat-radiating structure being a path through which the heat is transmitted to at least one of thermal vias through the adhesive filling the recessed portion and a second heat-radiating structure being a path through which the heat is transmitted to at least the other one of the thermal vias through the adhesive on the bottom surface of the cavity, other than the region where the recessed portion is provided.
3. The semiconductor device according to claim 1 , further comprising an additional recessed portion formed on the side wall of the cavity with which the semiconductor element is in close contact, the additional recessed portion being formed integrally with the recessed portion.
4. The semiconductor device according to claim 2 , wherein the first heat-radiating structure includes thermal vias formed more densely than those formed in the second heat-radiating structure, the thermal vias extending from the region of the bottom surface of the cavity to the outside of the board, the region being near the portion where the semiconductor element is in close contact with the side wall.
5. The semiconductor device according to claim 1 , wherein the first heat radiating structure includes thermal vias formed more densely than those formed in the second heat-radiating structure, the thermal vias extending from the bottom surface of the recessed portion to the outside of the board.
6. The semiconductor device according to claim 1 , wherein the wiring for higher frequency is a wiring for millimeter wave band.
7. The semiconductor device according to claim 1 , wherein the wiring board includes an antenna electrically connected to the wiring for higher frequency.
8. The semiconductor device according to claim 1 , wherein the wiring portion is exposed on a surface of the wiring board.
9. The semiconductor device according to claim 1 , wherein a length of the wiring for higher frequency compared with the other wirings within the wiring portion is shorter than that of the other wirings.