Solar cell

• US 8,604,338 B2
• Filed: 05/11/2012
• Issued: 12/10/2013
• Est. Priority Date: 03/24/2011
• Status: Active Grant

• Current Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Original Assignee: Panasonic Corporation (Panasonic Holdings Corporation)
• Inventors: Matsushita, Akio, Itoh, Akihiro, Nakagawa, Tohru, Ishida, Hidetoshi
• Primary Examiner(s): LEONG, SUSAN DANG
• Application Number:
  US13/469,794
• Publication Number:
  US 20120247555A1
• Time in Patent Office: 578 Days
• Field of Search: 136/205, 136/206, 136/214, 136/215, 136/244, 136/246, 136/247, 136/252
• US Class Current: 136/262
• CPC Class Codes: H01L 31/035281 Shape of the body
• CPC Class Codes: H01L 31/0543 comprising light concentrating means of the refractive type, e.g. lenses
• CPC Class Codes: H01L 31/0693 the devices including, apart from doping material or other impurities, only AIIIBV compounds, e.g. GaAs or InP solar cells
• CPC Class Codes: H01L 31/184 the active layers comprising only AIIIBV compounds, e.g. GaAs, InP
• CPC Class Codes: Y02E 10/544 Solar cells from Group III-V materials

Abstract

A method for generating electric power with use of a solar cell includes steps of: (a) preparing the solar cell including a condensing lens and a solar cell element, wherein the following inequation set (I) is satisfied: d2<d1, d3<d1, 1 nanometer≦d2≦4 nanometers, 1 nanometer≦d3≦4 nanometers, 100 nanometers≦w2, and 100 nanometers≦w3 . . . (I); and (b) irradiating a region S which is included in the surface of the p-type window layer through the condensing lens with light in such a manner that the following inequation (II) is satisfied so as to generate a potential difference between the n-side electrode (110) and the p-side electrode (109): w4≦w1 . . . (II).

Claims

1. A method for generating electric power with use of a solar cell, the method comprising steps of:

(a) preparing the solar cell comprising a condensing lens and a solar cell element, wherein

the solar cell element comprises an n-type GaAs layer, a p-type GaAs layer, a p-type window layer, an n-side electrode, and a p-side electrode;

a Z-direction denotes the direction of the normal line of the p-type GaAs layer;

an X-direction denotes a direction orthogonal to the Z-direction,

the n-type GaAs layer, the p-type GaAs layer, and the p-type window layer are stacked along the Z-direction;

the p-type GaAs layer is interposed between the n-type GaAs layer and the p-type window layer along the Z-direction;

the p-side electrode is electrically connected with the p-type GaAs layer;

the n-side electrode is electrically connected with the n-type GaAs layer;

the n-type GaAs layer is divided into a center part, a first peripheral part, and a second peripheral part;

the center part is interposed between the first peripheral part and the second peripheral part along the X-direction;

the first peripheral part and the second peripheral part have a shape of a layer,

the following inequation set (I) is satisfied;

d2<

d1, d3<

d1, 1 nanometer≦

d2≦

4 nanometers, 1 nanometer≦

d3≦

4 nanometers, 100 nanometers≦

w2, and 100 nanometers≦

w3 

 

(I);

wherein

d1 represents a thickness of the center part along the Z-direction;

d2 represents a thickness of the first peripheral part along the Z-direction;

d3 represents a thickness of the second peripheral part along the Z-direction;

w2 represents a width of the first peripheral part along the X-direction; and

w3 represents a width of the second peripheral part along the X-direction; and

(b) irradiating a region S which is included in the surface of the p-type window layer through the condensing lens with light in such a manner that the following inequation (II) is satisfied so as to generate a potential difference between the n-side electrode and the p-side electrode;

w4≦

w1 

 

(II);

wherein

w1 represents a width of the center part along the X-direction;

w4 represents a width of the region S along the X-direction in the cross-sectional view which includes the Z-direction; and

the first center part overlaps the region S when seen from the Z-direction.

2. The method according to claim 1, wherein

the width of the n-type GaAs layer is equal to the width of the p-type window layer.

3. The method according to claim 1, wherein

the solar cell element further comprises an n-type barrier layer interposed between the n-side electrode and the center part.

4. The method according to claim 1, wherein

the solar cell element further comprises an n-type contact layer interposed between the n-side electrode and the center part.

5. The method according to claim 1, wherein

the solar cell element further comprises a p-type contact layer interposed between the p-side electrode and the p-type GaAs layer.

6. The method according to claim 1, wherein

the sides of the n-type GaAs layer, the p-type GaAs layer, and the p-type window layer are covered with an insulating film.