CRYSTALLINE SILICON-BASED SOLAR CELL

• US 20130146132A1
• Filed: 08/03/2011
• Published: 06/13/2013
• Est. Priority Date: 08/09/2010
• Status: Abandoned Application

• Current Assignee: Kaneka Corporation
• Original Assignee: Kaneka Corporation
• Inventors: Kuchiyama, Takashi, Yamamoto, Kenji, Yoshimi, Masashi
• Application Number:
  US13/816,216
• Publication Number:
  US 20130146132A1
• Time in Patent Office: Days
• US Class Current: 136/255
• CPC Class Codes: H01L 31/022466 made of transparent conductive layers, e.g. TCO, ITO layers
• CPC Class Codes: H01L 31/022475 composed of indium tin oxide [ITO]
• CPC Class Codes: H01L 31/0747 comprising a heterojunction of crystalline and amorphous materials, e.g. heterojunction with intrinsic thin layer
• CPC Class Codes: H01L 31/202 including only elements of Group IV of the Periodic Table
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

The present invention improves a photoelectric conversion efficiency of a crystalline silicon-based solar cell. The crystalline silicon based solar cell includes a silicon-based thin-film of a first conductivity type and a first transparent electrode layer, in this order, on one surface of a conductive single-crystal silicon substrate, and a silicon-based thin-film of the opposite conductivity type and a second transparent electrode layer, in this order, on the other surface of the conductive single-crystal silicon substrate. The first and second transparent electrode layers are each formed of a transparent conductive metal oxide, and the first transparent electrode layer preferably has at least two layers, and a total thickness of 50 to 120 nm, wherein the carrier density of the substrate-side electroconductive layer is higher than that of the surface-side electroconductive layer, and the carrier density of the surface-side electroconductive layer is 1 to 4×10²⁰ cm⁻³.

Claims

1. A crystalline silicon-based solar cell comprising a silicon-based thin-film of a first conductivity type and a first transparent electrode layer, in this order, on one surface of a conductive single-crystal silicon substrate of the first conductivity type or an opposite conductivity type;

and a silicon-based thin-film of the opposite conductivity type and a second transparent electrode layer, in this order, on the other surface of the conductive single-crystal silicon substrate, wherein

the first transparent electrode layer and the second transparent electrode layer are each formed of a transparent conductive metal oxide, and

the first transparent electrode layer satisfies requirements (i) to (iii);

(i) at least two layers, including a substrate-side electroconductive layer and a surface-side electroconductive layer, are provided in the first transparent electrode layer, and the substrate-side electroconductive layer and the surface-side electroconductive layer are amorphous layers;

(ii) a total thickness of the first transparent electrode layer is 50 to 120 nm; and

(iii) a carrier density of the substrate-side electroconductive layer is higher than the carrier density of the surface-side electroconductive layer, and the carrier density of the surface-side electroconductive layer is 1 to 4×

10²⁰ cm<sup>−

3</sup>.

2. The crystalline silicon-based solar cell according to claim 1, wherein the crystalline silicon-based solar cell comprises a first intrinsic silicon-based thin-film between the conductive single-crystal silicon substrate and the silicon-based thin-film of the first conductivity type;

and a second intrinsic silicon-based thin-film between the conductive single-crystal silicon substrate and the silicon-based thin-film of the opposite conductivity type.

3. The crystalline silicon-based solar cell according to claim 1, wherein a thickness d_A of the substrate-side electroconductive layer is 5 nm to 40 nm.

4. The crystalline silicon-based solar cell according to claim 1, wherein a thickness d_A of the substrate-side electroconductive layer and a thickness d_B of the surface-side electroconductive layer satisfy 0.5≦

d_B/(d_A+d_B)≦

0.95.

7. The crystalline silicon-based solar cell according to claim 1, wherein a thickness of the conductive single-crystal silicon substrate is 250 μ

m or less.

8. The crystalline silicon-based solar cell according to claim 1, wherein the crystalline silicon-based solar cell further comprises a collecting electrode on each of the first transparent electrode layer and the second transparent electrode layer.

5. (canceled)

6. (canceled)