Solid-state image sensor including a photoelectric conversion element, a charge conversion element, and a light shielding element, method for producing the same solid-state image sensor, and electronic apparatus including the same solid-state image sensor

Patent metadata

Field	Value
Publication number	US-9659984-B2
Application number	US-201514593616-A
Country	US
Kind code	B2
Filing date	Jan 9, 2015
Priority date	Sep 16, 2011
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

A solid-state image sensor includes a semiconductor substrate having a photoelectric conversion element converting incident light into a charge and a charge retaining section temporarily retaining the charge photoelectrically converted by the photoelectric conversion element and a light shielding section having an embedded section extending in at least a region between the photoelectric conversion element and the charge retaining section of the semiconductor substrate.

First claim

What is claimed is:

1. An imaging device comprising:
a semiconductor substrate having a first side and a second side opposite the first side, wherein the first side is a light-incident side;
a first groove portion, a second groove portion, and third groove portion disposed in the semiconductor substrate such that a first region of the semiconductor substrate is between the first groove portion and the second groove portion and a second region of the semiconductor substrate is between the second groove portion and the third groove portion;
a first vertical light-blocking portion disposed in the first groove portion;
a second vertical light-blocking portion disposed in the second groove portion;
a third vertical light-blocking portion disposed in the third groove portion;
a horizontal light-blocking portion disposed above the second region of the semiconductor substrate, the second vertical light-blocking portion, and the first region of the semiconductor substrate, wherein the horizontal light-blocking portion is above at least a center portion of the second region of the semiconductor substrate and extends in a continuous manner to the first region of the semiconductor substrate; and
a metallic oxide film disposed adjacent to the first side of the semiconductor substrate,
wherein,
a depth dimension of the first vertical light-blocking portion, second vertical light-blocking portion, and third vertical light-blocking portion is larger than a width dimension of the respective first vertical light-blocking portion, second vertical light-blocking portion, and third vertical light-blocking portion in a cross-section view,
a width dimension of the horizontal light-blocking portion is larger than a depth dimension of the horizontal light-blocking portion in the cross-section view, and
the metallic oxide film is disposed in at least a part of the second groove portion.

2. The imaging device according to claim 1 , further comprising:
a wiring layer having a plurality of wirings, wherein the wiring layer is disposed adjacent to the second side of the semiconductor substrate.

3. The imaging device according to claim 1 , wherein the first vertical light-blocking portion is formed in such a way as to at least partially surround an impurity region.

4. The imaging device according to claim 1 , wherein the horizontal light-blocking portion is disposed in such a way as to cover at least a portion of an impurity region on a back side of the semiconductor substrate.

5. The imaging device according to claim 4 , wherein the horizontal light-blocking portion partially extends to a region corresponding to another impurity region.

6. The imaging device according to claim 1 , further including a front-side light-blocking portion disposed in such a way as to cover at least a portion of an impurity region on a front side of the semiconductor substrate.

7. The imaging device according to claim 6 , wherein
the front-side light-blocking portion partially extends to a region corresponding to at least a portion of a second impurity region.

8. The imaging device according to claim 1 , wherein the metallic oxide film is a material selected from the group consisting of silicon dioxide(SiO 2 ), hafnium oxide(HfO 2 ), tantalum pentoxide(Ta 2 O 5 ), zirconium dioxide(ZrO 2 ), and combinations thereof.

9. The imaging device according to claim 1 , further comprising:
a first impurity region and a second impurity region, wherein the first impurity region and the second impurity region include an n-type conductivity type portion and a p-type conductivity type portion.

10. The imaging device according to claim 1 , further comprising:
a first impurity region and a second impurity region disposed in the semiconductor substrate; and
a plurality of transistors disposed adjacent to the second side of the semiconductor substrate,
wherein,
the second vertical light-blocking portion is disposed between the first impurity region and the second impurity region.

11. The imaging device according to claim 10 , wherein the plurality of transistors includes a first transfer transistor associated with the first impurity region and a second transfer transistor associated with the second impurity region.

12. The imaging device according to claim 10 , wherein the plurality of transistors includes a reset transistor positioned to allow charge to be selectively discharged from a floating diffusion to a circuit node, and an amplification transistor coupled to the floating diffusion so as to allow a signal corresponding to a potential of the floating diffusion to be output to a signal line.

13. The imaging device according to claim 12 , wherein the plurality of transistors further includes a select transistor positioned to selectively enable operation of the amplification transistor.

14. The imaging device according to claim 12 , further comprising:
a column circuit coupled to the signal line and configured to perform correlated double sampling of the signal.

15. The imaging device according to claim 10 , further comprising:
a drive circuit configured to drive the plurality of transistors.

16. The imaging device according to claim 10 , wherein a wiring layer is disposed adjacent to the second side of the semiconductor substrate.

17. The imaging device according to claim 16 , wherein the wiring layer includes a signal line connected to at least one transistor of the plurality of transistors.

18. The imaging device according to claim 16 , wherein an oxide film is disposed between the semiconductor substrate and the wiring layer.

19. The imaging device according to claim 1 , further comprising:
a first impurity region and a second impurity region disposed in the semiconductor substrate.

20. The imaging device according to claim 1 , further comprising:
a digital signal processing circuit configured to receive and process a digital signal; and
a memory configured to receive and store a processed digital signal received from the digital signal processing circuit.

21. The imaging device according to claim 1 , further comprising:
an on-chip lens disposed adjacent the first side of the semiconductor substrate.

22. The imaging device according to claim 21 , further comprising:
a color filter disposed between the on-chip lens and the first side of the semiconductor substrate.

23. The imaging device according to claim 22 , wherein the color filter includes filters of at least two different colors selected from green, red, and blue.

24. The imaging device according to claim 1 , wherein the second vertical light-blocking portion and the horizontal light-blocking portion are connected to each other.

25. An electronic apparatus comprising:
an imaging device including:
a semiconductor substrate having a first side and a second side opposite the first side, wherein the first side is a light-incident side,
a first groove portion, a second groove portion, and a third groove portion disposed in the semiconductor substrate such that a first region of the semiconductor substrate is between the first groove portion and the second groove portion and a second region of the semiconductor substrate is between the second groove portion and the third groove portion,
a first vertical light-blocking portion disposed in the first groove portion,
a second vertical light-blocking portion disposed in the second groove portion,
a third vertical light-blocking portion dis

Assignees

• Sony Corp

Inventors

• Ohkubo Tomohiro
• Endo Suzunori

Classifications

• H04N25/76 Primary

  Addressed sensors, e.g. MOS or CMOS sensors · CPC title

• H01L27/14623 Primary

  Electricity · mapped topic

• H01L27/14629

  Electricity · mapped topic

• H04N5/374

  Electricity · mapped topic

• H01L27/1463

  Electricity · mapped topic