SOLID STATE IMAGING DEVICE, CAMERA MODULE, AND METHOD FOR MANUFACTURING SOLID STATE IMAGING DEVICE

• US 20110234893A1
• Filed: 03/16/2011
• Published: 09/29/2011
• Est. Priority Date: 03/24/2010
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: KOSEKI, Yoshiteru
• Granted Patent: US 8,669,631 B2
• Time in Patent Office: Days
• US Class Current: 348/374
• CPC Class Codes: H01L 2224/11 Manufacturing methods
• CPC Class Codes: H04N 23/57 Mechanical or electrical details of cameras or camera modules specially adapted for being embedded in other devices

Abstract

A solid state imaging device according to one embodiment of the present invention includes a substrate with a solid state imaging element, a first impurity layer, a plurality of external electrodes, and a translucent substrate. The first impurity layer is formed on a back surface side of the substrate, and forms a pn junction with the substrate. The plurality of external electrodes is formed on the back surface of the substrate and is electrically connected to the solid state imaging element. The translucent substrate is fixed to the substrate.

Claims

1. A solid state imaging device comprising:

a substrate including a solid state imaging element;

a first impurity layer formed on a back surface side of the substrate and forming a pn junction with the substrate;

a plurality of external electrodes formed on the back surface of the substrate and electrically connected to the solid state imaging element; and

a translucent substrate fixed on the substrate.

2. The solid state imaging device according to claim 1, wherein the first impurity layer is an amorphous layer.

3. The solid state imaging device according to claim 1, wherein

the substrate is a P-type silicon substrate, and

the first impurity layer is an N-type impurity layer formed by injecting germanium ions to the P-type silicon substrate.

4. The solid state imaging device according to claim 1, wherein

the substrate is an N-type silicon substrate, and

the first impurity layer is a P-type impurity layer formed by injecting arsenic ions to the N-type silicon substrate.

5. The solid state imaging device according to claim 1, wherein the first impurity layer is formed on the back surface of the substrate.

6. The solid state imaging device according to claim 1, wherein the first impurity layer is formed inside the substrate.

7. The solid state imaging device according to claim 1, further comprising a second impurity layer formed inside the substrate and having the same conductivity as the first impurity layer.

8. The solid state imaging device according to claim 7, wherein

the substrate is a P-type silicon substrate, and

the second impurity layer is an N-type impurity layer formed by injecting boron ions to the P-type silicon substrate.

9. The solid state imaging device according to claim 7, wherein

the substrate is an N-type silicon substrate, and

the second impurity layer is a P-type impurity layer formed by injecting phosphorous ions to the N-type silicon substrate.

10. The solid state imaging device according to claim 7, wherein the second impurity layer is formed on the first impurity layer.

11. The solid state imaging device according to claim 7, wherein the second impurity layer is formed above the first impurity layer.

12. The solid state imaging device according to claim 1, wherein

the substrate is a substrate including a plurality of through-holes, and

aground wiring for electrically connecting the solid state imaging element and the plurality of external electrodes and for grounding the solid state imaging element is formed on side surfaces of some of the plurality of through-holes.

13. A camera module comprising:

a tubular lens holder having a bottom, internally including a lens, and formed on the solid state imaging device according to claim 1; and

a tubular shield fixed to the lens holder to cover one part of the lens holder and the solid state imaging device according to claim 1, having a bottom, and including an opening at the bottom.

14. A camera module comprising:

a tubular lens holder having a bottom, internally including a lens, and formed on the solid state imaging device according to claim 7; and

a tubular shield fixed to the lens holder to cover one part of the lens holder and the solid state imaging device according to claim 7, having a bottom, and including an opening at the bottom.

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

injecting ions to a back surface of a substrate including a solid state imaging element to form a first impurity layer, which forms a pn junction with the substrate, on the back surface side of the substrate;

forming a plurality of through-holes in the substrate;

forming an insulating film on the back surface of the substrate and side surfaces of the plurality of through-holes;

forming a plurality of wirings to be connected to the solid state imaging element on a front surface of the insulating film; and

forming a plurality of external electrodes, each of which is to be connected to one part of the plurality of wirings, on the back surface of the substrate.

16. The method for manufacturing a solid state imaging device according to claim 15, wherein the step of forming the first impurity layer is a step of forming an amorphous layer by injecting germanium ions or arsenic ions to the back surface side of the substrate.

17. The method for manufacturing a solid state imaging device according to claim 15, further comprising the step of forming a second impurity layer having the same conductivity as the first impurity layer inside the substrate after the step of forming the first impurity layer.

18. The method for manufacturing a solid state imaging device according to claim 17, wherein the step of forming the second impurity layer is a step of injecting boron ions or phosphorous ions to the back surface side of the substrate.

19. The method for manufacturing a solid state imaging device according to claim 15, further comprising the step of:

removing the insulating film formed on the side surfaces of some of the plurality of through-holes before the step of forming the plurality of wirings, wherein

the step of forming the plurality of wirings is a step of forming a plurality of wirings on a front surface of the insulating film and the side surfaces of the plurality of through-holes from which the insulating film is removed.