Image sensor and manufacturing method thereof
The present disclosure provides a semiconductor structure, including a substrate including a first material, wherein the first material generates electrical signals from radiation within a first range of wavelengths, an image sensor element including a second material, wherein the second material generates electrical signals from radiation within a second range of wavelengths, the second range is different from first range, a transparent layer proximal to a light receiving surface of the image sensor element, wherein the transparent layer is transparent to radiation within the second range of wavelength, and an interconnect structure connected to a signal transmitting surface of the image sensor element.
1. A semiconductor structure, comprising:
a substrate comprising a first material, wherein the first material generates electrical signals from radiation within a first range of wavelengths;
an image sensor element comprising a second material, wherein the second material generates electrical signals from radiation within a second range of wavelengths, the second range is different from first range;
a first heavily doped region laterally surrounding the image sensor element;
a transparent layer proximal to a light receiving surface of the image sensor element, wherein the transparent layer is transparent to radiation within the second range of wavelength; and
an interconnect structure connected to a signal transmitting surface of the image sensor element.
2. The semiconductor structure of claim 1 , wherein the first heavily doped region is embedded in the second material.
3. The semiconductor structure of claim 1 , wherein the substrate further comprises a multiplication zone below the image sensing element.
4. The semiconductor structure of claim 3 , wherein the multiplication zone comprises:
a first implant region having a first conductivity type; and
a second implant region having a second conductivity type different from the first conductivity type, wherein the second implant region is below the first implant region.
5. The semiconductor structure of claim 4 , wherein the second implant region constitute a conductive path connected from the first implant region to the first heavily doped region.
6. The semiconductor structure of claim 1 , wherein the first heavily doped region comprises an upper portion with a first dopant concentration and a lower portion with a second dopant concentration, the first dopant concentration is greater than the second dopant concentration.
7. The semiconductor structure of claim 1 , wherein the image sensor element further comprises a multiplication zone proximal to the signal transmitting surface.
8. The semiconductor structure of claim 7 , wherein the multiplication zone comprises:
a first implant region having a first conductivity type; and
a second implant region having a second conductivity type different from the first conductivity type, wherein the second implant region is below the first implant region.
9. The semiconductor structure of claim 1 , wherein a concentration of dopant in the first heavily doped region is in a range from about 1×10 18 cm −3 to about 1×10 21 cm −3 .
10. A semiconductor structure, comprising:
a substrate comprising a first material, wherein the first material generates electrical signals from radiation within a first range of wavelengths;
an image sensor element comprising a second material, wherein the second material generates electrical signals from radiation within a second range of wavelengths, the second range is different from first range; and
a guard ring region proximal to the image sensor element and facing a light-receiving surface of the substrate.
11. The semiconductor structure of claim 10 , wherein the guard ring is below a bottom surface of the image sensor element.
12. The semiconductor structure of claim 10 , further comprising a first heavily doped region laterally surrounding the image sensor element.
13. The semiconductor structure of claim 12 , further comprising:
a first implant region having a first conductivity type, wherein the first implant region is laterally surrounded by the guard ring; and
a second implant region having a second conductivity type different from the first conductivity type, wherein the second implant region is below the first implant region.
14. The semiconductor structure of claim 10 , further comprising:
a first implant region having a first conductivity type; and
a second implant region having a second conductivity type different from the first conductivity type, wherein the second implant region is laterally surrounded by the guard ring.
15. A semiconductor structure, comprising:
a substrate comprising a first material, wherein the first material generates electrical signals from radiation within a first range of wavelengths;
an image sensor element comprising a second material, wherein the image sensor element is disposed in a recessed portion of the substrate, and the second material generates electrical signals from radiation within a second range of wavelengths, the second range is different from first range;
a transparent layer proximal to a light receiving surface of the image sensor element, wherein the transparent layer is transparent to radiation within the second range of wavelength; and
a plurality of microstructure portions at an interface between the substrate and the transparent layer.
16. The semiconductor structure of claim 15 , further comprising an interconnect structure connected to a signal transmitting surface of the image sensor element.
17. The semiconductor structure of claim 15 , further comprising a silicon capping layer over the image sensor element.
18. The semiconductor structure of claim 17 , further comprising an oxide film over the silicon capping layer and the image sensor element.
19. The semiconductor structure of claim 15 , further comprising a guard ring overlapping with the image sensor element, wherein the guard ring is doped with an N-type dopant.
20. The semiconductor structure of claim 15 , further comprising a shielding layer disposed in the transparent layer.