Semiconductor device and method of manufacturing the same
View Patent ↗The invention provides a semiconductor device with high reliability and smaller size and a method of manufacturing the same. A light emitting element as a device element is formed on the front surface of a semiconductor substrate, for example. In detail, an N-type semiconductor layer, a P-type semiconductor layer and pad electrodes are formed on the front surface of the semiconductor substrate. A device element receiving light from the light emitting element (e.g. a photodiode element), for example, and pad electrodes are formed on the front surface of another semiconductor substrate. The semiconductor substrates are attached and integrated with an adhesive layer being interposed therebetween. Wiring layers electrically connected to the pad electrodes and wiring layers electrically connected to the other pad electrodes are formed on the side surface of the semiconductor substrate.
1. A semiconductor device, comprising:
a first substrate comprising a first device element formed on a front surface thereof;
a second substrate comprising a second device element formed on a front surface thereof;
a first pad electrode disposed on the front surface of the first substrate and electrically connected to the first device element;
a second pad electrode disposed on the front surface of the second substrate and electrically connected to the second device element; and
an adhesive layer disposed between the front surface of the first substrate and the front surface of the second substrate so that the first and second substrates are adhered together to form an integrated die,
wherein, in plan view of the semiconductor device, the first pad electrode does not overlap any pad electrode formed on the front surface of the second substrate, and the second pad electrode does not overlap any pad electrode formed on the front surface of the first substrate.
2. The semiconductor device of claim 1 , further comprising a first conductive terminal electrically connected to the first pad electrode and a second conductive terminal electrically connected to the second pad electrode, the first and the second conductive terminals extending in a direction normal to the front surfaces of the first and second substrates.
3. The semiconductor device of claim 1 , further comprising a first wiring layer electrically connected to the first pad electrode and a second wiring layer electrically connected to the second pad electrode, the first and the second wiring layers being disposed on side surfaces of the second substrate.
4. The semiconductor device of claim 3 , wherein the first and the second wiring layers extend to cover a back surface of the second substrate.
5. The semiconductor device of claim 1 , further comprising penetration holes penetrating the second substrate and filled with a conductive member, the first and second pad electrodes being configured to be electrically connected to an external power supply through the filled penetration holes.
6. The semiconductor device of claim 1 , wherein part of the adhesive layer is removed above the first pad electrode so as to accommodate a conductive member for external power connection to the first pad electrode.
7. The semiconductor device of claim 1 , wherein the first device element comprises a light emitting element, and the second device element comprises a light receiving element receiving light from the light emitting element.
8. The semiconductor device of claim 1 , wherein the first device element or the second device element comprises a MEMS element.
9. The semiconductor device of claim 1 , wherein the first pad electrode is electrically separated from the second pad electrode.