Solid state image pick-up device

• US 20060055799A1
• Filed: 11/07/2005
• Published: 03/16/2006
• Est. Priority Date: 07/17/2000
• Status: Active Grant

• Current Assignee: Adeia Semiconductor Advanced Technologies Inc. (f/k/a Tessera Advanced Technologies, Inc.) (Adeia Inc.)
• Original Assignee: Renesas Electronics Corporation
• Inventors: Ohkubo, Hiroaki, Nakashiba, Yasutaka
• Granted Patent: US 8,233,063 B2
• Time in Patent Office: Days
• US Class Current: 348/294
• CPC Class Codes: G06V 40/1318 using electro-optical elements or layers, e.g. electroluminescent sensing
• CPC Class Codes: G06V 40/1329 Protecting the fingerprint sensor against damage caused by the finger

Abstract

The solid state image pick-up device comprises a chip wherein an object to be photographed is put directly on the back surface of the chip, a light incident on the object enters the inner portion of the chip, signal electric charges generated in the inner portion of the chip by the light, the signal electric charges are collected in a photo detective region and the photo detective region has a barrier diffusion layer adjacent thereto so as to collect the signal electric charges effectively. The above-mentioned structure of the solid state image pick-up device can provide superior features that the chip of the solid state image pick-up device is protected from the deterioration of elements included in the chip and the destruction of the elements by Electro Static Discharge, resulting in the reliability improvement of the chip.

Claims

1. A solid state image pick-up device comprising

a semiconductor substrate, and

a photo detective region formed in one surface region of said semiconductor substrate,

wherein light incident on an object on another surface of said semiconductor substrate enters an inner portion of said semiconductor substrate, said photo detective region collects signal electric charges that are generated in said inner portion of said semiconductor substrate by said incident light and said signal electric charges are outputted to be converted to an image of said object, and

wherein said another surface is connected to a reference potential.

2. The solid state image pick-up device according to claim 1, wherein an insulation layer is formed on said another surface of said semiconductor substrate and said light enters said inner portion of said semiconductor substrate after penetrating said insulation layer.

3. The solid state image pick-up device according to claim 2, wherein said insulation layer comprises at least any one of a silicon dioxide film, a silicon nitride film and a silicon oxy nitride film.

6. The solid state image pick-up device according to claim 1, wherein said light comprises a visible light or a near infrared light or an infrared light.

7. The solid state image pick-up device according to claim 1, wherein said semiconductor substrate has one conduction type, said photo detective region has a photo detective diffusion layer having another conduction type opposite to said one conduction type and an impurity density of said semiconductor substrate is less than 1×

10¹⁷/cm³.

16. The solid state image pick-up device according to claim 1, wherein elements formed in said semiconductor substrate constitute a CMOS image sensor.

17. The solid state image pick-up device according to claim 1, wherein elements formed in said semiconductor substrate constitute a CCD image sensor.

20. The solid state image pick-up device according to claim 1, wherein said reference potential is ground.

4. A solid state image pick-up device comprising

a semiconductor substrate, and

a photo detective region formed in one surface region of said semiconductor substrate,

wherein light incident on an object on another surface of said semiconductor substrate enters an inner portion of said semiconductor substrate, said photo detective region collects signal electric charges that are generated in said inner portion of said semiconductor substrate by said incident light and said signal electric charges are outputted to be converted to an image of said object, and

wherein after said object is put on said another surface of said semiconductor substrate, said light enters said inner portion of said semiconductor substrate while said object is still on said another surface of said semiconductor substrate.

18. The solid state image pick-up device according to claim 4, wherein said another surface is connected to a reference potential.

19. The solid state image pick-up device according to claim 18, wherein said reference potential is ground.

5. (canceled)

8-15. -15. (canceled)

21. A device comprising:

a semiconductor substrate having a front surface and a rear surface opposing to said front surface;

a photo detective region formed in said front surface of semiconductor substrate;

wherein

said rear surface of said semiconductor substrate is in direct contact with an object to be imaged.

22. The device according to claim 21, wherein said rear surface has an insulation layer therein, and said insulation layer serves as being in direct contact with an object to be

23. The device according to claim 21, wherein said rear surface is connected to a reference potential.

24. The device according to claim 23, wherein said reference potential is ground.

25. A solid-state image pickup device comprising:

a semiconductor substrate having a front surface and a rear surface;

a photo detective layer formed in said semiconductor substrate at a side of said front surface and detecting a light entering through said rear surface, said photo detective layer having;

a first region having a first conductive type;

a plurality of second regions having a second conductive type opposite to said first conductive type, each of said second regions constituting a photo diode and being separated from each other by said first region; and

a third region contacting to a bottom surface of one of said second regions and having said first conductive type, said third region being lower in impurity density than said first surface.

26. The solid-state image pickup device according to claim 25, wherein said first region is deeper than said second regions.

27. The solid-state image pickup device according to claim 25, further comprising a MOSFET formed in said first region, said MOSFET dumps a charge accumulated in one of said second regions.

28. The solid-state image pickup device according to claim 27, wherein

said MOSFET has a source and drain regions of said second conductive type, one of said source and drain regions contacts with one of said second regions.