SOLID-STATE IMAGING DEVICE, METHOD OF MANUFACTURING THE SAME, AND ELECTRONIC EQUIPMENT

• US 20110241148A1
• Filed: 03/24/2011
• Published: 10/06/2011
• Est. Priority Date: 03/31/2010
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Watanabe, Kazufumi, Hiyama, Susumu
• Granted Patent: US 8,445,985 B2
• Time in Patent Office: Days
• US Class Current: 257/435
• CPC Class Codes: H01L 27/14612 involving a transistor
• CPC Class Codes: H01L 27/1462 Coatings
• CPC Class Codes: H01L 27/14621 Colour filter arrangements
• CPC Class Codes: H01L 27/14623 Optical shielding
• CPC Class Codes: H01L 27/14627 Microlenses
• CPC Class Codes: H01L 27/14629 Reflectors
• CPC Class Codes: H01L 27/1463 Pixel isolation structures
• CPC Class Codes: H01L 27/14636 Interconnect structures
• CPC Class Codes: H01L 27/1464 Back illuminated imager structures
• CPC Class Codes: H01L 27/14643 Photodiode arrays; MOS imagers

Abstract

A solid state imaging device including a semiconductor layer comprising a plurality of photodiodes, a first antireflection film located over a first surface of the semiconductor layer, a second antireflection film located over the first antireflection film, a light shielding layer having side surfaces which are adjacent to at least one of first and the second antireflection film.

Claims

1. A solid state imaging device comprising:

a semiconductor layer comprising a plurality of photodiodes;

a first antireflection film located over a first surface of the semiconductor layer;

a second antireflection film located over the first antireflection film; and

a light shielding layer having side surfaces which are adjacent to at least one of the first and the second antireflection film.

2. The solid state imaging device of claim 1 wherein the light shielding layer is located between the first antireflection film and the second antireflection film.

3. The solid state imaging device of claim 2 including an intermediate layer located between the first antireflection film and the light shielding layer.

4. The solid state imaging device of claim 1 wherein the light shielding layer is embedded in the second antireflection film.

5. The solid state imaging device of claim 1 including a separation region between each of the plurality of photodiodes.

6. The solid state imaging device of claim 5 wherein the light shielding layer is located over the separation region.

7. The solid state imaging device of claim 5 including

a trench located in each of the separation regions,

wherein,

the light shielding layer is located inside the trench.

8. The solid state imaging device of claim 1 wherein the photodiode has a first surface which receives light.

9. The solid state imaging device of claim 8 wherein the first antireflection film and the second antireflection film are located over the first surface of the photodiode.

10. The solid state imaging device of claim 1 wherein the thickness of the first antireflection film is smaller than the thickness of the second antireflection film.

11. The solid state imaging device of claim 1 wherein the light shielding layer has a substantially convex shape.

12. The solid state imaging device of claim 1 wherein the first antireflection film includes at least one of an oxide of hafnium, zirconium, aluminum, tantalum, titanium, magnesium, yttrium, lanthanoid or silicon element.

13. The solid state imaging device of claim 1 wherein the second antireflection film includes at least one of an oxide of hafnium, zirconium, aluminum, tantalum, titanium, magnesium, yttrium, lanthanoid or silicon element.

14. The solid state imaging device of claim 1 wherein, the first antireflection film has a refraction index of 1.5 or more.

15. The solid state imaging device of claim 14 wherein the second antireflection film has a refraction index of 1.5 or more

16. The solid state imaging device of claim 1 including a wiring layer located over a second surface of the semiconductor layer opposite the first antireflection film and the second antireflection film.

17. The solid state imaging device of claim 15 including a transistor located over the second surface of the semiconductor layer.

18. The solid state imaging device of claim 17 wherein the transistor transfers an electric charge from the photodiode to a transmission line.

19. A method for manufacturing a solid state imaging device comprising the steps of:

forming a semiconductor layer comprising a plurality of photodiodes;

forming a first antireflection film over a first surface of the semiconductor layer;

forming a second antireflection film over the first antireflection film; and

forming a light shielding layer having side surfaces,

wherein,

the side surfaces are adjacent to at least one of the first antireflection film and the second antireflection film.

20. The method of claim 19 wherein the second antireflection film is formed after forming the light shielding layer.

21. The method of claim 19 wherein the light shielding layer is formed after forming the second antireflection film.

22. The method of claim 19 wherein the light shielding layer is located between the first antireflection film and the second antireflection film.

23. The method of claim 22 including the step of forming an intermediate layer located between the first antireflection film and the light shielding layer.

24. The method of claim 22 wherein the light shielding layer is embedded in the second antireflection film.

25. The method of claim 19 including the step of forming a separation region between each of the plurality of photodiodes.

26. The method of claim 19 wherein the light shielding layer is located over the separation region.

27. The method of claim 25 including

a trench located in each of the separation regions,

wherein,

the light shielding layer is located inside the trench.

28. The method of claim 19 wherein the photodiode has a first surface which receives light.

29. The method of claim 28 wherein the first antireflection film and the second antireflection film are located over the first surface of the photodiode.

30. The method of claim 19 wherein the thickness of the first antireflection film is smaller than the thickness of the second antireflection film.

31. The method of claim 19 wherein the light shielding layer has a substantially convex shape.

32. The method of claim 19 wherein the first antireflection film includes at least one of an oxide of hafnium, zirconium, aluminum, tantalum, titanium, magnesium, yttrium, lanthanoid or silicon element.

33. The method of claim 19 wherein the second antireflection film includes at least one of an oxide of hafnium, zirconium, aluminum, tantalum, titanium, magnesium, yttrium, lanthanoid element or silicon element.

34. The method of claim 19 wherein the first antireflection film has a refraction index of 1.5 or more.

35. The method of claim 34 wherein the second antireflection film has a refraction index of 1.5 or more.

36. The method of claim 19 including the step of forming a wiring layer over a second surface of the semiconductor layer opposite the first antireflection film and the second antireflection film.

37. The method of claim 36 including forming a transistor over the second surface of the semiconductor layer.

38. The method of claim 37 wherein the transistor transfers an electric charge from the photodiode to a transmission line.

39. An electronic apparatus comprising:

a semiconductor layer including a plurality of photodiodes;

a first antireflection film on a first surface of the semiconductor layer;

a second antireflection film over the first antireflection film;

a light shielding layer adjacent the first antireflection film; and

a photodiode layer having a side surface adjacent at least the second antireflection film.