Solid-state imaging device and electronic device including light-shielding film for suppression of light leakage to memory
The present disclosure relates to a solid-state imaging device and an electronic device which efficiently capture incident light to improve sensitivity while maintaining the effect of suppressing noise generation. A memory is located on a side opposite from a light receiving surface and formed in the same substrate of Si as a photoelectric conversion element. The substrate including Si is defined by digging the Si deep from the light receiving surface, at a position where the memory is formed, and a bottom light-shielding film is formed at a bottom portion of the defined hole. The present disclosure is applicable to, for example, a stacked and back-illuminated solid-state imaging device.
1. A solid-state imaging device, comprising:
a memory that is located on a side opposite from a light receiving surface and formed in a same substrate of Si as a photoelectric conversion element;
a bottom light-shielding film that is formed at a bottom portion of a hole defined by digging the Si deep from the light receiving surface, at a position where the memory is formed;
a light-transmitting film that is formed to fill the hole over the bottom light-shielding film in the hole;
a top light-shielding film that is formed on part of the light-transmitting film after the light-transmitting film is planarized; and
a digging light-shielding film that is formed by digging the light-transmitting film to connect the top light-shielding film and the bottom light-shielding film.
2. The solid-state imaging device according to claim 1 , wherein the light-transmitting film includes a material having a refractive index smaller than a refractive index of the Si.
3. The solid-state imaging device according to claim 2 , wherein the light-transmitting film includes an oxide film.
4. The solid-state imaging device according to claim 1 , further comprising an embedded light-shielding film that is formed by being embedded near the memory from a side opposite from the light receiving surface.
5. The solid-state imaging device according to claim 4 , wherein the bottom light-shielding film is formed to be connected to the embedded light-shielding film.
6. The solid-state imaging device according to claim 1 , wherein the bottom light-shielding film is formed to fill the hole entirely.
7. The solid-state imaging device according to claim 1 , further comprising a global shutter function.
8. An electronic device, comprising:
a solid-state imaging device that includes:
a memory that is located on a side opposite from a light receiving surface and formed in a same substrate of Si as a photoelectric conversion element;
a bottom light-shielding film that is formed at a bottom portion of a hole defined by digging the Si deep from the light receiving surface, at a position where the memory is formed;
a light-transmitting film that is formed to fill the hole over the bottom light-shielding film in the hole;
a top light-shielding film that is formed on part of the light-transmitting film after the light-transmitting film is planarized; and
a digging light-shielding film that is formed by digging the light-transmitting film to connect the top light-shielding film and the bottom light-shielding film;
a signal processing circuit configured to process an output signal output from the solid-state imaging device; and
an optical system configured to input incident light into the solid-state imaging device.
9. The electronic device according to claim 8 , wherein the light-transmitting film includes a material having a refractive index smaller than a refractive index of the Si.
10. The electronic device according to claim 9 , wherein the light-transmitting film includes an oxide film.
11. The electronic device according to claim 8 , further comprising an embedded light-shielding film that is formed by being embedded near the memory from a side opposite from the light receiving surface.
12. The electronic device according to claim 11 , wherein the bottom light-shielding film is formed to be connected to the embedded light-shielding film.
13. The electronic device according to claim 8 , wherein the bottom light-shielding film is formed to fill the hole entirely.
14. The electronic device according to claim 8 , further comprising a global shutter function.