Semiconductor device and method of manufacturing the same, and electronic apparatus
A semiconductor device is provided as a back-illuminated solid-state imaging device. The device is manufactured by bonding a first semiconductor wafer with a pixel array in a half-finished product state and a second semiconductor wafer with a logic circuit in a half-finished product state together, making the first semiconductor wafer into a thin film, electrically connecting the pixel array and the logic circuit, making the pixel array and the logic circuit into a finished product state, and dividing the first semiconductor wafer and the second semiconductor being bonded together into microchips.
1. A semiconductor device comprising:
a first semiconductor wafer having a light incident side and including a pixel section, the pixel section including a photodiode and at least one of a transfer transistor, a reset transistor, or an amplification transistor;
a second semiconductor wafer including a logic circuit, the logic circuit including a signal processing unit, wherein the first semiconductor wafer and the second semiconductor wafer are bonded to each other;
a first multi-wiring layer formed at a side opposite to the light incident side of the first semiconductor wafer, wherein the first multi-wiring layer is connected to the pixel section;
a second multi-wiring layer formed at a first side of the second semiconductor wafer, wherein the side opposite to the light incident side of the first semiconductor wafer and the first side of the second semiconductor wafer face each other;
a connection conductor extending from the light incident side of the first semiconductor wafer to the second multi-wiring layer through the first semiconductor wafer in a peripheral section other than the pixel section; and
an insulating layer disposed on a top surface of the connection conductor,
wherein,
the connection conductor extends to the second multi-wiring layer by penetrating the first semiconductor wafer, and
the connection conductor has a first connection point connected to a wiring in the first multi-wiring layer and a second connection point connected to a part of the logic circuit.
2. The semiconductor device according to claim 1 , wherein the connection conductor connects at least a lower wiring layer of the first multi-wiring layer and at least an upper wiring layer of the second multi-wiring layer.
3. The semiconductor device according to claim 2 , wherein the connection conductor connects a lowest wiring layer of the first multi-wiring layer and an uppermost wiring layer of the second multi-wiring layer.
4. The semiconductor device of claim 2 , wherein the connection conductor connects the pixel section and the logic circuit.
5. The semiconductor device of claim 2 , wherein the lower wiring layer of the first multi-wiring layer is connected to other wiring layers in the first multi-wiring layer.
6. The semiconductor device according to claim 1 , wherein a thickness of the first semiconductor wafer is less than a thickness of the second semiconductor wafer.
7. The semiconductor device according to claim 1 , wherein the first semiconductor wafer and the second semiconductor wafer are bonded by using a plasma bonding.
8. The semiconductor device according to claim 7 , wherein at least one of a plasma TEOS film, a plasma SiN film, a SiON film, or a SiC film is formed on a bonding surface of the first semiconductor wafer or the second semiconductor wafer.
9. The semiconductor device according to claim 1 , further including a color filter formed on the light incident side of the first semiconductor wafer.
10. The semiconductor device according to claim 1 , further including a micro-lens formed on the light incident side of the first semiconductor wafer, wherein the connection conductor is formed in a predetermined area not corresponding to the micro-lens on the light incident side of the first semiconductor wafer.
11. The semiconductor device of claim 1 , wherein a depth of the connection conductor is about 5 μm to about 15 μm.
12. The semiconductor device of claim 1 , wherein a contact area of the first connection point is 1 to 5 μm in diameter.
13. The semiconductor device of claim 1 , wherein a contact area of the second connection point is 1 to 5 μm in diameter.
14. The semiconductor device according to claim 1 , wherein the insulating layer includes a planarizing layer.
15. The semiconductor device according to claim 1 , wherein the insulating layer is disposed above the connection conductor and the pixel section.
16. The semiconductor device according to claim 1 , further including a color filter formed on the light incident side of the first semiconductor wafer and disposed on the insulating layer in the pixel section.
17. The semiconductor device according to claim 1 , wherein the first multi-wiring layer is disposed between the pixel section and the second semiconductor wafer.
18. An electronic apparatus, comprising:
an imaging device, including:
a first semiconductor wafer having a light incident side and including a pixel section, the pixel section including a photodiode and at least one of a transfer transistor, a reset transistor, or an amplification transistor;
a second semiconductor wafer including a logic circuit, the logic circuit including a signal processing unit, wherein the first semiconductor wafer and the second semiconductor wafer are bonded to each other;
a first multi-wiring layer formed at a side opposite to the light incident side of the first semiconductor wafer, wherein the first multi-wiring layer is connected to the pixel section;
a second multi-wiring layer formed at a first side of the second semiconductor wafer, wherein the side opposite to the light incident side of the first semiconductor wafer and the first side of the second semiconductor wafer face each other;
a connection conductor extending from the light incident side of the first semiconductor wafer to the second multi-wiring layer through the first semiconductor wafer in a peripheral section other than the pixel section;
an insulating layer disposed on a top surface of the connection conductor,
wherein,
the connection conductor extends to the second multi-wiring layer by penetrating the first semiconductor wafer, and
the connection conductor has a first connection point connected to a wiring in the first multi-wiring layer and a second connection point connected to a part of the logic circuit;
an optical system that introduces incident light into the photodiode; and
a signal processing circuit that processes an output signal from the imaging device.