Back side illumination image sensors and electronic device including the same
In some example embodiments, a back side illumination (BSI) image sensor may include a pixel configured to generate electrical signals in response to light incident on a back side of a substrate. In some example embodiments, the pixel includes, a photodiode, a device isolation film adjacent to the photodiode, a dark current suppression layer above the photodiode, a light shield grid above the photodiode and including an opening area of 1 to 15% of an area of the pixel, a light shielding filter layer above the light shield grid, a planarization layer above the light shielding filter layer, a lens above the planarization layer, and/or an anti-reflective film between the photodiode and the lens.
1. An image sensor comprising:
a substrate;
a photodiode in the substrate;
a light shield grid on the photodiode, the light shield grid including a first opening above the photodiode;
a plurality of sub-films covering the first opening, wherein the plurality of sub-films comprise a first sub-film and a second sub-film;
a light shielding filter layer formed above the plurality of sub-films,
the light shielding filter layer including a second opening;
a planarization layer formed above the light shielding filter layer; and
a lens disposed above the planarization layer,
wherein the first opening is vertically aligned with the second opening.
2. The image sensor of claim 1 , wherein the first opening is circular.
3. The image sensor of claim 2 , wherein the first sub-film has a first refractive index and the second sub-film has a second refractive index different from the first refractive index.
4. The image sensor of claim 3 , wherein the plurality of sub-films further comprise third to tenth sub-films on the second sub-film.
5. The image sensor of claim 4 , wherein at least two of the first to tenth sub-films have a same refractive index.
6. The image sensor of claim 3 , wherein the plurality of sub-films include a plurality of low refractive index films and a plurality of high refractive index films alternately laminated on the plurality of low refractive index films.
7. The image sensor of claim 6 , wherein each of high refractive index films has a refractive index within a range of 2.0 to 2.8.
8. The image sensor of claim 6 , wherein each of low refractive index films has a refractive index within a range of 1.2 to 1.8.
9. The image sensor of claim 8 , wherein the plurality of sub-films include 10 to 40 sub-films.
10. The image sensor of claim 8 , wherein a transparent material is disposed in the first opening.
11. An image sensor comprising:
a substrate;
a photodiode in the substrate;
a first opening above the photodiode;
a plurality of sub-films covering the first opening wherein the plurality of sub-films comprise a first sub-film and a second sub-film;
a light shielding filter layer formed above the plurality of sub-films,
the light shielding filter layer including a second opening;
a planarization layer formed above the light shielding filter layer; and
a lens disposed above the planarization layer,
wherein a width of the second opening is greater than a width of the first opening.
12. The image sensor of claim 11 , wherein the second opening is vertically aligned with the first opening.
13. The image sensor of claim 12 , wherein the first sub-film has a first refractive index and the second sub-film has a second refractive index different from the first refractive index.
14. The image sensor of claim 13 further comprising third to tenth sub-films formed above the second sub-film.
15. The image sensor of claim 14 , wherein at least two of the first to tenth sub-films have a same refractive index.
16. The image sensor of claim 13 , wherein the plurality of sub-films include a plurality of low refractive index films and a plurality of high refractive index films alternately laminated on the plurality of low refractive index films.
17. The image sensor of claim 16 , wherein each of high refractive index films has a refractive index within a range of 2.0 to 2.8.
18. The image sensor of claim 16 , wherein each of low refractive index films has a refractive index within a range of 1.2 to 1.8.
19. An image sensor comprising:
a substrate;
a photodiode in the substrate;
a light shield grid on the photodiode, the light shield grid including a first opening above the photodiode;
a plurality of sub-films comprising a first sub-film disposed above the first opening;
a light shielding filter layer formed above the plurality of sub-films,
the light shielding layer filter including a second opening;
a planarization layer formed above the light shielding filter layer; and
a lens disposed above the planarization layer,
wherein a width of a first end of the second opening is different from a width of a second end of the second opening.
20. The image sensor of claim 19 , wherein the plurality of sub-films include a plurality of low refractive index films and a plurality of high refractive index films alternately laminated on the plurality of low refractive index films.