Amorphous semiconductor solar cell

• US 5,104,455 A
• Filed: 01/07/1991
• Issued: 04/14/1992
• Est. Priority Date: 01/09/1990
• Status: Expired due to Term

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Inoue, Yasumi, Yokota, Akitoshi, Moriuchi, Sota, Nakata, Yukihiko, Sannomiya, Hitoshi, Itoh, Manabu
• Primary Examiner(s): Weisstuch, Aaron
• Application Number:
  US07/638,571
• Time in Patent Office: 463 Days
• Field of Search: 136/249 TJ, 136/255, 136/258 AM, 357/30 J, 357/30 K
• US Class Current: 136/249
• CPC Class Codes: H01L 31/0352 characterised by their shape or by the shapes, relative sizes or disposition of the semiconductor regions
• CPC Class Codes: H01L 31/03765 including AIVBIV compounds or alloys, e.g. SiGe, SiC
• CPC Class Codes: H01L 31/075 the potential barriers being only of the PIN type, e.g. amorphous silicon PIN solar cells
• CPC Class Codes: H01L 31/076 Multiple junction or tandem solar cells
• CPC Class Codes: H01L 31/204 including AIVBIV alloys, e.g. SiGe, SiC
• CPC Class Codes: Y02E 10/548 Amorphous silicon PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

An amorphous semiconductor solar cell includes an i type layer which is an at least partially alloyed, substantially intrinsic semiconductor, an n type layer formed on one side of the i type layer, and a p type layer formed n the other side of the i type layer, and the i type layer has its energy bandgap varied in a thickness direction to have a bandgap larger than the bandgap of the p type layer in the vicinity of the interface with the p type layer.

Claims

1. An amorphous semiconductor solar cell, comprising:

an i type layer formed of an at least partly alloyed, substantially intrinsic amorphous semiconductor;

an n type amorphous semiconductor layer formed on one side of said i type layer; and

a p type amorphous semiconductor layer formed on the other side of said i type layer;

wherein said i type layer includes a first sub layer having a bandgap varied in the thickness direction thereof to have a maximum bandgap larger than the bandgap of said p type layer near its interface with said p type layer.

2. The amorphous semiconductor solar cell according to claim 1, wherein said i type layer further includes a second sub layer having a bandgap minimum between said first sub layer and said n type layer.

3. The amorphous semiconductor solar cell according to claim 2, wherein the bandgap of said i type layer varies continuously.

4. The amorphous semiconductor solar cell according to claim 2, wherein said i type layer includes a portion in which the bandgap varies discontinuously.

5. The amorphous semiconductor solar cell according to claim 2, said i type layer including a sub-layer of a SiGe alloy and a sub-layer of a-SiC alloy.

6. The amorphous semiconductor solar cell according to claim 5, said i type layer further including an a-Si sub-layer.

7. The amorphous semiconductor solar cell according to claim 2, said i type layer including at least a sub-layer of a-SiC alloy.

8. The amorphous semiconductor solar cell according to claim 7, said i type layer further including a sub-layer of a-Si.

9. The amorphous semiconductor solar cell according to claim 1, further comprising:

additional semiconductor layers provided on at least one side of said n type layer and said p type layer in order to produce a tandem type structure in which a plurality of p-i-n junctions are formed.