Image sensor

1 . An image sensor comprising:

a substrate;

a plurality of unit pixels, each of the plurality of unit pixels including a photoelectric conversion element in the substrate, the substrate defining a first trench in a lattice shape to isolate the plurality of unit pixels;

a plurality of first capacitor structures extended within the first trench, including a first electrode layer on a first sidewall of the first trench, a second electrode layer on a second sidewall of the first trench, and a first dielectric layer extending to a bottommost surface of the first trench and separating the first electrode layer and the second electrode layer, the first dielectric layer separated from the first sidewall and the second sidewall, the first electrode layer including one of a metal layer or a metal nitride layer, the second electrode layer including one of a metal layer or a metal nitride layer; and

a plurality of first capacitor isolation patterns at respective lattice points of the first trench to isolate the plurality of first capacitor structures.

2 . The image sensor of claim 1 , further comprising:

a second capacitor isolation pattern between ones of the plurality of the first capacitor isolation patterns adjacent to each other to isolate the plurality of first capacitor structures.

3 . The image sensor of claim 2 , wherein a distance between the second capacitor isolation pattern and a respective one of the plurality of first capacitor isolation patterns adjacent to one side of the second capacitor isolation pattern is same as a distance between the second capacitor isolation pattern and another respective one of the plurality of first capacitor isolation patterns adjacent to another side of the second capacitor isolation pattern.

4 . The image sensor of claim 2 , wherein a distance between the second capacitor isolation pattern and a respective one of the plurality of first capacitor isolation patterns adjacent to one side of the second capacitor isolation pattern is different from a distance between the second capacitor isolation pattern and another respective one of the plurality of first capacitor isolation patterns adjacent to another side of the second capacitor isolation pattern.

5 . The image sensor of claim 1 , wherein each of the plurality of first capacitor isolation patterns includes a same material as that of the substrate.

6 . The image sensor of claim 1 , wherein each of the plurality of the first capacitor isolation patterns includes a material different from that of the substrate.

7 . The image sensor of claim 1 , further comprising:

a first insulating layer extended along the first sidewall of the first trench and a second insulating layer extended along the second sidewall of the first trench,

wherein the first electrode layer is between the first insulating layer and the first dielectric layer, and the second electrode layer is between the first dielectric layer and the second insulating layer.

8 . The image sensor of claim 1 , wherein each of the plurality of first capacitor structures includes a second dielectric layer and a third electrode layer, which are extended along and within the first trench, the second dielectric layer being between the second electrode layer and the third electrode layer.

9 . The image sensor of claim 1 , wherein

any one of the plurality of unit pixels includes a first subpixel and a second subpixel,

the substrate defines a second trench to isolate the first subpixel from the second subpixel, and

each of the first and second subpixels includes the photoelectric conversion element, and further includes:

a second capacitor structure extended along a sidewall of the second trench in the second trench, including a third electrode layer, a fourth electrode layer, and a second dielectric layer between the third electrode layer and the fourth electrode layer; and

a second capacitor isolation pattern at a point where the second trench and the first trench cross each other to isolate the plurality of first capacitor structures from the second capacitor structure.

10 . An image sensor comprising:

a substrate;

a first unit pixel and a second unit pixel adjacent to the first unit pixel in a first direction, the substrate defining a first trench extended in a second direction inside the substrate to isolate the first unit pixel from the second unit pixel, including a first sidewall and a second sidewall, which are opposite to each other in the first direction; and

a first capacitor structure including a first electrode layer on and extended along the first sidewall of the first trench, a second electrode layer on and extended along the second sidewall of the first trench, and a first dielectric layer extending to a bottommost surface of the first trench and separating the first electrode layer and the second electrode layer, the first dielectric layer separated from the first sidewall and the second sidewall, the first electrode layer including one of a metal layer or a metal nitride layer, the second electrode layer including one of a metal layer or a metal nitride layer.

11 . The image sensor of claim 10 , wherein

the first unit pixel includes a first subpixel including a first photoelectric conversion element and a second subpixel including a second photoelectric conversion element, and

the substrate defines a second trench extended in the second direction to isolate the first subpixel from the second subpixel, including a third sidewall and a fourth sidewall, which are opposite to each other in the first direction,

the first unit pixel further includes:

a second capacitor structure including a fifth electrode layer extended along the third sidewall of the second trench, a sixth electrode layer extended along the fourth sidewall of the second trench, and a third dielectric layer between the fifth electrode layer and the sixth electrode layer.

12 . The image sensor of claim 11 , wherein the second trench penetrates the substrate in the second direction.

13 . The image sensor of claim 10 , further comprising:

a first color filter corresponding to the first unit pixel on the substrate; and

a second color filter corresponding to the second unit pixel on the substrate, isolated from the first color filter,

wherein the first color filter is configured to sense a same color as that of the second color filter.

14 . The image sensor of claim 10 , further comprising:

a first color filter corresponding to the first unit pixel on the substrate; and

a second color filter corresponding to the second unit pixel on the substrate, isolated from the first color filter,

wherein the first color filter is configured to sense a color different from that of the second color filter.

15 . The image sensor of claim 10 , wherein the first capacitor structure includes:

a third electrode layer extended along the second sidewall of the first trench in the first trench; and

a second dielectric layer between the second electrode layer and the third electrode layer.

16 . The image sensor of claim 10 , wherein the first trench and the first capacitor structure penetrate the substrate in the second direction.

17 . The image sensor of claim 16 , further comprising a wiring structure on a second surface of the substrate,

wherein the wiring structure includes:

a first pad connected to the first electrode layer on the second surface of the substrate;

a second pad connected to the second electrode layer on the second surface of the substrate;

a first contact on the first pad; and

a second contact on the second pad.

18 . The image sensor of claim 10 , further comprising:

a first insulating layer extended along the first sidewall of the first trench; and

a second insulating layer extended along the second sidewall of the first trench, wherein

the first electrode layer is between the first insulating layer and the first dielectric layer, and

the second electrode layer is between the first dielectric layer and the second insulating layer.

19 . An image sensor comprising:

a substrate including a first surface and a second surface, which are opposite to each other;

a plurality of unit pixels, each of the plurality of unit pixels including a photoelectric conversion element in the substrate, the substrate defining a first trench surrounding a periphery of each of the plurality of unit pixels inside the substrate and isolating the plurality of unit pixels;

a first insulating layer on a first sidewall of the first trench;

a second insulating layer on a second sidewall of the first trench;

a plurality of first capacitor structures filling the first trench between the first insulating layer and the second insulating layer, within the first trench and extended along an extended direction of the first trench, and including a first electrode layer on the first sidewall of the first trench, a second electrode layer on the second sidewall of the first trench, and a first dielectric layer extending to a bottommost surface of the first trench and separating the first electrode layer and the second electrode layer, the first dielectric layer separated from the first sidewall and the second sidewall, the first electrode layer including one of a metal layer or a metal nitride layer, the second electrode layer including one of a metal layer or a metal nitride layer;

a plurality of first capacitor isolation patterns at respective intersection points of the first trench to isolate the plurality of first capacitor structures;

a wiring structure on the second surface of the substrate, including a first contact connected to the first electrode layer and a second contact connected to the second electrode layer; and

a color filter and a micro lens, which are sequentially stacked on the first surface of the substrate.

20 . The image sensor of claim 19 , wherein each of the plurality of unit pixels has a polygonal shape.