Solid state imaging device, method of manufacturing solid-state imaging device, and electronic apparatus
The present technique aims to provide a solid-state imaging device that reduces shading and color mixing between pixels. The present invention also provides a method of manufacturing the solid-state imaging device. The present technique further relates to a solid-state imaging device that enables provision of an electronic apparatus that uses the solid-state imaging device, a method of manufacturing the solid-state imaging device, and an electronic apparatus. The solid-state imaging device includes a substrate, pixels each including a photoelectric conversion unit formed in the substrate, and a color filter layer formed on the light incidence surface side of the substrate. The solid-state imaging device also includes a device isolating portion that is formed to divide the color filter layer and the substrate for the respective pixels, and has a lower refractive index than the refractive indexes of the color filter layer and the substrate.
1. An imaging device comprising:
a semiconductor substrate having a first side as a light-incident side and a second side opposite to the first side;
a first photoelectric conversion region formed in the semiconductor substrate;
a first color filter disposed over the first photoelectric conversion region;
a second photoelectric conversion region formed in the semiconductor substrate;
a second color filter disposed over the second photoelectric conversion region;
a first insulating film disposed at the first side of the semiconductor substrate, wherein at least a portion of the first insulating film is disposed above the first and second photoelectric conversion regions;
a second insulating film disposed between the first color filter and the second color filter; and
a trench formed in the semiconductor substrate, the trench including:
a fixed charge film disposed at the first side of the semiconductor substrate, wherein at least a portion of the fixed charge film extends from the first side of the semiconductor substrate towards the second side of the semiconductor substrate.
2. The imaging device according to claim 1 , wherein at least a portion of the second insulating film is within the trench.
3. The imaging device according to claim 2 , wherein the portion of the fixed charge film is between the first insulating film and at least one of the first and second photoelectric conversion regions.
4. The imaging device according to claim 3 , wherein the first insulating film includes silicon.
5. The imaging device according to claim 4 ,
wherein the second insulating film is between the portion of the fixed charge film and another portion of the fixed charge film, wherein the second insulating film includes silicon.
6. The imaging device according to claim 5 , wherein the fixed charge film includes hafnium.
7. The imaging device according to claim 1 , wherein at least a part of the portion of the fixed charge film adjoins a p-type region, wherein the p-type region is a p-well region.
8. The imaging device according to claim 1 ,
wherein the fixed charge film surrounds the second insulating film on three sides in a cross-sectional view.
9. The imaging device according to claim 8 , wherein the first color filter and the second color filter pass different wavelengths of light.
10. The imaging device according to claim 8 , wherein the first insulating film extends beyond a light-incident side of the first and second color filters.
11. The imaging device according to claim 8 , wherein the first and second color filters have a thickness of 1 μm or greater.
12. The imaging device according to claim 1 , further comprising a light-scattering structure at a light-incident surface side of the first and second photoelectric conversion regions.
13. The imaging device according to claim 1 , wherein the trench further comprises a nontransparent film.
14. The imaging device according to claim 13 , wherein the nontransparent film includes a metal material.
15. The imaging device according to claim 1 , wherein the fixed charge film is disposed on both sides of at least one of the first photoelectric conversion region and the second photoelectric conversion region.
16. The imaging device according to claim 15 , wherein the portion of the fixed charge film extends from a surface of the first and second color filters into the semiconductor substrate.
17. The imaging device according to claim 16 , wherein the first color filter and the second color filter pass different wavelengths of light.
18. The imaging device according to claim 1 , wherein at least part of the fixed charge film is embedded within a p-type region.
19. An apparatus comprising:
an imaging device including:
a semiconductor substrate having a first side as a light-incident side and a second side opposite to the first side;
a first photoelectric conversion region formed in the semiconductor substrate;
a first color filter disposed over the first photoelectric conversion region;
a second photoelectric conversion region formed in the semiconductor substrate;
a second color filter disposed over the second photoelectric conversion region;
a first insulating film disposed at the first side of the semiconductor substrate, wherein at least a portion of the first insulating film is disposed above the first and second photoelectric conversion regions;
a second insulating film disposed between the first color filter and the second color filter; and
a trench formed in the semiconductor substrate, the trench including:
a fixed charge film disposed at the first side of the semiconductor substrate, wherein at least a portion of the fixed charge film extends from the first side of the semiconductor substrate towards the second side of the semiconductor substrate; and
at least one lens disposed above the imaging device.