Solid-state image pickup element, image pickup device, and method of manufacturing solid-state image pickup element
The solid-state image pickup element includes a pixel, a light-receiving-surface-sided trench, and a light-receiving-surface-sided shielding member. A plurality of protrusions is formed on the light-receiving surface of the pixel in the solid-state image pickup element. In addition, the light-receiving-surface-sided trench is formed around the pixel having the plurality of protrusions formed, at the light-receiving surface in the solid-state image pickup element. In addition, the light-receiving-surface-sided member is buried in the light-receiving-surface-sided trench formed around the pixel having the plurality of protrusions formed on the light-receiving surface in the solid-state image pickup element. In addition, the photoelectric conversion region of a near-infrared-light pixel expands to the surface side opposed to the light-receiving surface of the photoelectric conversion region of a visible-light pixel. In addition, a trench is further formed inside the pixel at a surface opposed to the light-receiving surface.
1. A solid-state image pickup element, comprising:
a pixel having a plurality of protrusions on a light-receiving surface of the pixel, wherein
an interval between respective representative points of the plurality of protrusions is one of 250 nanometers or more,
the pixel includes:
an infrared-light pixel comprising a first photoelectric conversion portion to photoelectrically convert infrared light, and
a visible-light pixel comprising a second photoelectric conversion portion to photoelectrically convert visible light, and
each of the first photoelectric conversion portion and the second photoelectric conversion portion is below the light-receiving surface in a first direction;
a light-receiving-surface-sided trench around the pixel, wherein
the light-receiving-surface-sided trench is at the light-receiving surface of the pixel,
the first photoelectric conversion portion has a first depth in the first direction,
the light-receiving-surface-sided trench has a second depth in the first direction,
the second photoelectric conversion portion has a third depth in the first direction, and
the second depth of the light-receiving-surface-sided trench is smaller than the first depth of the first photoelectric conversion portion and greater than the third depth of the second photoelectric conversion portion; and
a light-receiving-surface-sided member buried in the light-receiving-surface-sided trench.
2. The solid-state image pickup element according to claim 1 , wherein the interval between the respective representative points of the plurality of protrusions is substantially identical to a divisor of the pixel in size in a second direction parallel to the light-receiving surface of the pixel.
3. The solid-state image pickup element according to claim 1 , wherein the plurality of protrusions is in a partial region of the pixel at the light-receiving surface of the pixel.
4. The solid-state image pickup element according to claim 1 , wherein the light-receiving-surface-sided trench is two micrometers or more in depth.
5. The solid-state image pickup element according to claim 1 , wherein the light-receiving-surface-sided member includes a member with a first refractive index lower than a second refractive index of the pixel.
6. The solid-state image pickup element according to claim 1 , wherein the light-receiving-surface-sided member includes metal.
7. The solid-state image pickup element according to claim 1 , wherein the plurality of protrusions is on the infrared-light pixel.
8. The solid-state image pickup element according to claim 1 , wherein the plurality of protrusions is on the infrared-light pixel and the visible-light pixel.
9. The solid-state image pickup element according to claim 1 , further comprising:
a near-infrared-light interrupting filter configured to interrupt the infrared light towards the visible-light pixel,
wherein the near-infrared-light interrupting filter is between the visible-light pixel and an image pickup lens.
10. The solid-state image pickup element according to claim 1 , wherein
the first photoelectric conversion portion expands beneath the second photoelectric conversion portion in the first direction.
11. The solid-state image pickup element according to claim 1 , further comprising a plurality of pixels, wherein
each pixel of the plurality of pixels is configured to receive light having a different wavelength, and
each pixel of the plurality of pixels includes a photoelectric conversion portion having a depth corresponding to a wavelength of the received light.
12. The solid-state image pickup element according to claim 1 , further comprising a plurality of pixels, wherein
each pixel of the plurality of pixels receives light having a different wavelength, and
the interval between the respective representative points of the plurality of protrusions has a value corresponding to wavelength of the light received by each pixel with the plurality of protrusions.
13. The solid-state image pickup element according to claim 1 , further comprising:
an opposed-surface-sided trench on an opposed surface opposite to the light-receiving surface of a substrate having the pixel; and
an opposed-surface-sided member buried in the opposed-surface-sided trench.
14. The solid-state image pickup element according to claim 13 , wherein the opposed-surface-sided member includes a member with a first refractive index lower than a second refractive index of the pixel.
15. An image pickup device, comprising:
a solid-state image pickup element including:
a pixel having a plurality of protrusions on a light-receiving surface of the pixel, wherein
an interval between respective representative points of the plurality of protrusions is one of 250 nanometers or more,
the pixel includes:
an infrared-light pixel comprising a first photoelectric conversion portion to photoelectrically convert infrared light, and
a visible-light pixel comprising a second photoelectric conversion portion to photoelectrically convert visible light, and
each of the first photoelectric conversion portion and the second photoelectric conversion portion is below the light-receiving surface in a first direction;
a light-receiving-surface-sided trench around the pixel, wherein
the light-receiving-surface-sided trench is at the light-receiving surface of the pixel,
the first photoelectric conversion portion has a first depth in the first direction,
the light-receiving-surface-sided trench has a second depth in the first direction,
the second photoelectric conversion portion has a third depth in the first direction, and
the second depth of the light-receiving-surface-sided trench is smaller than the first depth of the first photoelectric conversion portion and greater than the third depth of the second photoelectric conversion portion; and
a light-receiving-surface-sided member buried in the light-receiving-surface-sided trench; and
an image pickup lens configured to guide light to the solid-state image pickup element.
16. The image pickup device according to claim 15 , further comprising:
an infrared-light interrupting filter configured to interrupt the infrared light; and
an insertion and removal unit configured to:
insert the infrared-light interrupting filter into a specific position between the image pickup lens and the solid-state image pickup element; and
remove the infrared-light interrupting filter from the specific position.
17. The image pickup device according to claim 15 , wherein the solid-state image pickup element further includes a signal processing unit configured to process a pixel signal from the pixel.
18. A method of manufacturing a solid-state image pickup element, the method comprising:
forming a pixel on a substrate;
forming a plurality of protrusions on a light-receiving surface of the pixel, wherein
an interval between respective representative points of the plurality of protrusions is one of 250 nanometers or more, and
the pixel includes:
an infrared-light pixel comprising a first photoelectric conversion portion to photoelectrically convert infrared light, and
a visible-light pixel comprising a second photoelectric conversion portion to photoelectrically convert visible light, and
each of the first photoelectric conversion portion and the second photoelectric conversion portion is below the light-receiving surface in a first direction;
forming, as a light-receiving-surface-sided trench, a trench around the pixel wherein
the light-receiving-surface-sided trench is on the light-receiving surface of the pixel,
the first photoelectric conversion portion has a first depth in the first direction,
the light-receiving-surface-sided trench has a second depth in the first direction,
the second photoelectric conversion portion has a third depth in the first direction, and
the second depth of the light-receiving-surface-sided trench is smaller than the first depth of the first photoelectric conversion portion and greater than the third depth of the second photoelectric conversion portion; and
burying a light-receiving-surface-sided member in the light-receiving-surface-sided trench.
19. The method according to claim 18 , further comprising forming the plurality of protrusions by wet etching.