PHOTODIODE DEVICE BASED ON WIDE BANDGAP MATERIAL LAYER AND BACK-SIDE ILLUMINATION (BSI) CMOS IMAGE SENSOR AND SOLAR CELL INCLUDING THE PHOTODIODE DEVICE

• US 20120175636A1
• Filed: 11/21/2011
• Published: 07/12/2012
• Est. Priority Date: 01/12/2011
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Ihara, Hisanori
• Granted Patent: US 8,987,751 B2
• Time in Patent Office: Days
• US Class Current: 257/77
• CPC Class Codes: H01L 27/1461 characterised by the photosensitive area
• CPC Class Codes: H01L 27/14632 Wafer-level processed structures
• CPC Class Codes: H01L 27/1464 Back illuminated imager structures
• CPC Class Codes: H01L 27/14687 Wafer level processing
• CPC Class Codes: H01L 31/02161 for devices characterised by at least one potential jump barrier or surface barrier
• CPC Class Codes: H01L 31/02162 for filtering or shielding light, e.g. multicolour filters for photodetectors
• CPC Class Codes: H01L 31/02327 the optical elements being integrated or being directly associated to the device, e.g. back reflectors optical coatings H01L31/0216
• CPC Class Codes: H01L 31/103 the potential barrier being of the PN homojunction type
• CPC Class Codes: Y02E 10/52 PV systems with concentrators

Abstract

According to example embodiments, a photodiode system may include a substrate, and at least one photodiode in the substrate, and a wideband gap material layer on a first surface of the substrate. The at least one photodiode may be between an insulating material in a horizontal plane. According to example embodiments, a back-side-illumination (BSI) CMOS image sensor and/or a solar cell may include a photodiode device. The photodiode device may include a substrate, at least one photodiode in the substrate, a wide bandgap material layer on a first surface of the substrate, and an anti-reflective layer (ARL) on the wide bandgap material layer.

Claims

1. A back-side-illumination (BSI) complementary-metal-oxide-semiconductor (CMOS) image sensor comprising:

a photodiode device including,

a substrate;

at least one photodiode in the substrate; and

a wide bandgap material layer on a first surface of the substrate;

a metal interconnection layer disposed on a second surface of the semiconductor substrate;

an anti-reflective layer (ARL) on the wide bandgap material layer;

a color filter on the ARL; and

a microlens on the color filter.

2. The sensor of claim 1, wherein

the wide bandgap material layer includes a material having a low absorption coefficient with respect to blue light.

3. The sensor of claim 1, wherein

the wide bandgap material layer includes one of p⁺-SiC, p⁺-SiN, and p⁺-SiCN.

4. The sensor of claim 1, further comprising:

a p⁺-silicon layer between the wide bandgap material layer and the substrate; and

the substrate includes a p⁻

-type silicon substrate.

5. The sensor of claim 1, wherein

the substrate includes a pixel array region and a peripheral circuit region, and

the wide bandgap material layer is on the entire pixel array region.

6. The sensor of claim 1, wherein

the substrate is includes a pixel array region and a peripheral circuit region, and

the wide bandgap material layer is formed only on a portion of the pixel array region corresponding to a blue pixel.

7. The sensor of claim 1, wherein

the wide bandgap material layer includes a p⁺-SiC layer obtained by implanting carbon (C) ions into a p⁺-silicon layer.

8. The sensor of claim 7, wherein

the substrate is a p⁻

-type silicon substrate,

the p⁺-silicon layer is on the substrate, and

the wide bandgap material layer is formed by implanting C ions into one of the entire region of the p⁺-silicon layer and a partial upper region of the p⁺-silicon layer.

9. The sensor of claim 7, wherein

the wide bandgap material layer is a laser annealed layer.

10. The sensor of claim 1, wherein

the ARL includes one of

a first structure including a silicon nitride (SiN_x) layer,

a second structure including a buffer layer and a hafnium oxide (HfO₂) layer,

a third structure including a silicon oxide (SiO₂) layer and a silicon oxynitride (SiON) layer,

a fourth structure including a buffer layer, a SiN_x layer, and a titanium oxide (TiO₂) layer,

a fifth structure including a buffer layer, a HfO₂ layer, and a TiO₂ layer,

a sixth structure including a buffer layer, a slot plasma antenna (SPA) oxide layer, a SiN_x layer, and a TiO₂ layer,

a seventh structure including a buffer layer, an SPA oxide layer, a SiN_x layer, and a TiO₂ layer,

an eighth structure including a buffer layer, an SPA oxide layer, and a SiN_x layer,

a ninth structure including a buffer layer, an SPA oxide layer, a hafnium silicon oxide (HfSiO_x) layer, and a TiO₂ layer, and

a tenth structure including a buffer layer, a HfSiO_x layer, and a TiO₂ layer.

11. The sensor of claim 10, further comprising:

a passivation layer on the ARL.

12. A solar cell comprising:

a photodiode device including,

a substrate,

at least one photodiode in the substrate, and

a wide bandgap material layer on a first surface of the substrate,

an anti-reflective layer (ARL) on the wide bandgap material layer;

a first electrode layer in the ARL and electrically connected to the photodiode device; and

a second electrode layer on a second surface of the semiconductor substrate and electrically connected to the photodiode device.

13. The solar cell of claim 12, wherein

the wide bandgap material layer includes a material having a low absorption coefficient with respect to blue light.

14. The solar cell of claim 12, wherein

the wide bandgap material layer includes one of p⁺-SiC, p⁺-SiN, and p⁺-SiCN.

15. The solar cell of claim 12, wherein

the photodiode includes a PN junction diode structure through the entire thickness of the substrate, and

the wide bandgap material layer is between an n-type semiconductor layer of the photodiode and the anti-reflective layer.

16. A photodiode system comprising:

a substrate;

at least one photodiode in the substrate,

the at least one photodiode in between an insulating material in a horizontal plane; and

a wide bandgap material layer on a first surface of the substrate.

17. A solar cell comprising the photodiode system of claim 16, and further including:

a first electrode electrically connected to the at least one photodiode;

a second electrode electrically connected to the at least one photodiode; and

wherein the wide bandgap material layer includes one of p⁺-SiC, p⁺-SiN, and p⁺-SiCN.

18. An image sensor comprising the photodiode system of claim 16, and further including:

a color filter on the at least one photodiode;

a microlens on the color filter;

a metal interconnection layer;

wherein the at least one photodiode is on the metal interconnection layer and between the color filter and the metal interconnection layer.

19. A unit pixel comprising:

the photodiode system of claim 16;

a transfer transistor operatively connected to the at least one photodiode of the photodiode system and configured to transfer charges generated by the at least one photodiode of the photodiode system to a floating diffusion region in the substrate for storage;

a reset transistor operatively connected to the floating diffusion region, the reset transistor configured to reset charges stored in the floating diffusion region;

a drive transistor configured to buffer signals corresponding to charges stored in the floating diffusion region; and

a select transistor operatively connected to the drive transistor, the select transistor configured for selecting the unit pixel.

20. An imaging system comprising:

a CMOS image sensor including the photodiode system of claim 16;

a bus operatively connecting the CMOS image sensor to a processor,

the processor configured to process an output of the CMOS image sensor.