CIGS COMPOUND SOLAR CELL

• US 20150027537A1
• Filed: 02/25/2013
• Published: 01/29/2015
• Est. Priority Date: 02/27/2012
• Status: Active Grant

• Current Assignee: Nitto Denko Corporation
• Original Assignee: Nitto Denko Corporation
• Inventors: Teraji, Seiki, Kawamura, Kazunori, Nishii, Hiroto, Watanabe, Taichi
• Granted Patent: US 9,947,808 B2
• Time in Patent Office: Days
• US Class Current: 136/262
• CPC Class Codes: H01L 31/02167 for solar cells
• CPC Class Codes: H01L 31/022466 made of transparent conductive layers, e.g. TCO, ITO layers
• CPC Class Codes: H01L 31/0322 comprising only AIBIIICVI chalcopyrite compounds, e.g. Cu In Se2, Cu Ga Se2, Cu In Ga Se2
• CPC Class Codes: H01L 31/0328 including, apart from doping materials or other impurities, semiconductor materials provided for in two or more of groups H01L31/0272 - H01L31/032
• CPC Class Codes: H01L 31/03923 including AIBIIICVI compound materials, e.g. CIS, CIGS
• CPC Class Codes: H01L 31/0749 including a AIBIIICVI compound, e.g. CdS/CulnSe2 [CIS] heterojunction solar cells
• CPC Class Codes: Y02E 10/541 CuInSe2 material PV cells

Abstract

In order to provide a CIGS compound solar cell with a high conversion efficiency, a CIGS compound solar cell including a rear electrode layer, a CIGS light absorbing layer, a buffer layer, and a transparent electrode layer in this order over a substrate is configured such that the buffer layer comprises a mixed crystal of a Group IIa metal and zinc oxide, and characteristics of the mixed crystal as shown by X-ray diffraction satisfy the following formula (1):

0.5≦A/(A+B+C)<1   (1)

(where none of A, B, C are 0)

• • A: peak intensity at plane (002)
  • B: peak intensity at plane (100)
  • C: peak intensity at plane (101).

Claims

1. A CIGS compound solar cell comprising:

at least a Group I-III-VI compound semiconductor layer,

a buffer layer, and

a transparent electrode in this order over a substrate,

wherein the buffer layer comprises a mixed crystal of a Group IIa metal and zinc oxide, and

wherein characteristics of the mixed crystal as shown by X-ray diffraction satisfy the following formula (1);

0.5≦

A/(A+B+C)<

1  

 

(1)

where none of A, B, C are 0

A;

peak intensity at plane (002)

B;

peak intensity at plane (100)

C;

peak intensity at plane (101).

2. The CIGS compound solar cell according to claim 1, wherein characteristics of the mixed crystal as shown by X-ray diffraction satisfy the following formula (2):

0<

B/(A+B+C)<

0.2  

 

(2);

where none of A, B, C are 0

A;

peak intensity at plane (002)

B;

peak intensity at plane (100)

C;

peak intensity at plane (101).

3. The CIGS compound solar cell according to claim 1, wherein characteristics of the mixed crystal as shown by X-ray diffraction satisfy the following formula (3):

0<

C/(A+B+C)<

0.3  

 

(3)

where none of A, B, C are 0

A;

peak intensity at plane (002)

B;

peak intensity at plane (100)

C;

peak intensity at plane (101).

4. The CIGS compound solar cell according to claim 1, wherein characteristics of the mixed crystal as shown by X-ray diffraction satisfy the following formula (4):

0.7<

(A+C)/(A+B+C)<

1  

 

(4)

where none of A, B, C are 0

A;

peak intensity at plane (002)

B;

peak intensity at plane (100)

C;

peak intensity at plane (101).

5. The CIGS compound solar cell according to claim 2, wherein characteristics of the mixed crystal as shown by X-ray diffraction satisfy the following formula (3):

0<

C/(A+B+C)<

0.3  

 

(3)

where none of A, B, C are 0

A;

peak intensity at plane (002)

B;

peak intensity at plane (100)

C;

peak intensity at plane (101).

6. The CIGS compound solar cell according to claim 2, wherein characteristics of the mixed crystal as shown by X-ray diffraction satisfy the following formula (4):

0.7<

(A+C)/(A+B+C)<

1  

 

(4)

where none of A, B, C are 0

A;

peak intensity at plane (002)

B;

peak intensity at plane (100)

C;

peak intensity at plane (101).

7. The CIGS compound solar cell according to claim 3, wherein characteristics of the mixed crystal as shown by X-ray diffraction satisfy the following formula (4):

0.7<

(A+C)/(A+B+C)<

1  

 

(4)

where none of A, B, C are 0

A;

peak intensity at plane (002)

B;

peak intensity at plane (100)

C;

peak intensity at plane (101).