Image sensor and method for manufacturing the same
View Patent ↗Embodiments relate to an image sensor and a method of manufacturing the same. According to embodiments, an image sensor may include a first substrate having circuitry formed thereon. It may further include a photodiode bonded to the first substrate and electrically connected to the circuitry, and a contact plug at a pixel border that may be electrically connected with the circuitry and the photodiode. According to embodiments, the photodiode may include a first conductive type ion implantation region selectively provided in a crystalline semiconductor layer, and a second conductive type ion implantation region in contact with one side surface of the first conductive type ion implantation region.
1. A device, comprising:
a first substrate with circuitry formed thereon;
a photodiode bonded to the first substrate and electrically connected to the circuitry, the photodiode comprising a first conductive type ion implantation region selectively provided in a crystalline semiconductor layer, and a second conductive type ion implantation region in contact with one side surface of the first conductive type ion implantation region;
a contact plug at a pixel border and electrically connected with the circuitry and the photodiode, wherein a first side surface of the contact plug is electrically contacted with the first conductive type ion implantation region of the photodiode, and a second side surface of the contact plug is insulated by a dielectric; and
an upper electrode electrically contacting the second conductive type ion implantation region of the photodiode.
2. The device of claim 1 , wherein the circuitry comprises one of a 1 transistor CMOS image sensor, a 2 transistor CMOS image sensor, a 3 transistor CMOS image sensor, and a 4 transistor CMOS image sensor.
3. The device of claim 1 , comprising a high concentration first conductive type ion implantation region between the first conductive type ion implantation region and the contact plug.
4. The device of claim 1 , comprising a high concentration first conductive type ion implantation region between the first conductive type ion implantation region and the contact plug.
5. The device of claim 1 , wherein the contact plug comprises at least one of tungsten, a single layer of titanium, and a titanium/titanium nitride (Ti/TiN) multilayer structure.
6. A method, comprising:
preparing a first substrate including circuitry and wiring;
preparing a second substrate including a photodiode;
bonding the first substrate and the second substrate to contact the photodiode and a first dielectric;
exposing the photodiode by removing a lower side of the second substrate; and
electrically connecting the wiring to the photodiode,
wherein the photodiode comprises a first conductive type ion implantation region selectively provided in a crystalline semiconductor layer, and a second conductive type ion implantation region in contact with one side surface of the first conductive type ion implantation region,
wherein electrically connecting the wiring to the photodiode comprises forming a contact plug at a pixel boundary, and
wherein a first side surface of the contact plug is electrically contacted with the first conductive type ion implantation region of the photodiode, and a second side surface of the contact plug is insulated by a second dielectric.
7. The method of claim 6 , wherein the crystalline semiconductor layer comprises a monocrystalline semiconductor layer.
8. The method of claim 6 , wherein the circuitry comprises one of a 1 transistor CMOS image sensor, a 2 transistor CMOS image sensor, a 3 transistor CMOS image sensor, and a 4 transistor CMOS image sensor.
9. The method of claim 6 , comprising providing an upper electrode electrically coupled to the second conductive type ion implantation region.
10. The method of claim 6 , comprising forming the first dielectric on the first substrate to selectively contact the wiring, after preparing the first substrate.
11. The method of claim 10 , wherein the wiring is electrically coupled to the photodiode by a contact plug formed at a pixel boundary, and a first side surface of the contact plug is electrically coupled to the first conductive type ion implantation region, and a second side surface of the contact plug is insulated by a second dielectric.
12. The method of claim 10 , wherein electrically connecting the wiring and the photodiode comprises:
defining a first contact hole to selectively expose the wiring by removing the photodiode and the first dielectric at a pixel boundary;
forming a barrier layer over the first contact hole and the photodiode;
providing a second dielectric over the barrier layer to fill the first contact hole;
defining a second contact hole by removing the second dielectric to expose the barrier layer at a side surface and a side at a bottom surface of the first contact hole;
defining a third contact hole by removing the exposed barrier layer and selectively exposing a side surface of the photodiode and the wiring; and
forming a contact plug to fill the third contact hole.
13. The method of claim 12 , wherein the barrier layer comprises a silicon nitride (SIN) layer.
14. The method of claim 12 , wherein removing the photodiode and the first dielectric, at the pixel boundary comprises performing a wet etch.
15. The method of claim 12 , wherein defining the first, second, and third contact holes comprises performing a wet etch.
16. The method of claim 12 , wherein the contact plug comprises at least one of tungsten, a single layer of titanium, and a titanium/titanium nitride (Ti/TiN) multilayer structure.