Photovoltaic generator

• US 6,281,428 B1
• Filed: 12/03/1999
• Issued: 08/28/2001
• Est. Priority Date: 09/01/1999
• Status: Expired due to Term

• Current Assignee: Opto Tech Corporation (OptoTech Corp.)
• Original Assignee: Opto Tech Corporation (OptoTech Corp.)
• Inventors: Lai, Steven, Chiu, John C. C.
• Primary Examiner(s): CHAPMAN, MARK A
• Application Number:
  US09/453,558
• Time in Patent Office: 634 Days
• Field of Search: 136/255
• US Class Current: 136/255
• CPC Class Codes: H01L 31/068 the potential barriers being only of the PN homojunction type, e.g. bulk silicon PN homojunction solar cells or thin film polycrystalline silicon PN homojunction solar cells
• CPC Class Codes: H01L 31/0682 back-junction, i.e. rearside emitter, solar cells, e.g. interdigitated base-emitter regions back-junction cells
• CPC Class Codes: Y02E 10/547 Monocrystalline silicon PV cells

Abstract

A photovoltaic generator comprising a substrate; an insulating layer provided on the substrate; first impurity diffusion zones formed on the insulating layer; second impurity diffusion zones deep enough to reach the insulating layer and of an opposite polarity to that of the first impurity diffusion zones the second impurity diffusion zones and the first impurity diffusion zones being alternately positioned on the surface of the substrate to form substantially vertical pn junctions; third impurity diffusion zones provided on the surface of the first impurity diffusion zones and the second impurity diffusion zones opposite to the insulating layer and of the same polarity as that of the second impurity diffusion zones, one end of each of the third impurity diffusion zones connecting, to the adjacent one of the second impurity diffusion zones while the other end connecting to the adjacent one of the first impurity diffusion zones; fourth impurity diffusion zones formed on the surface of the adjacent one of the first impurity diffusion zones and the adjacent one of the second impurity diffusion zones opposite to the insulating layer and being a heavily doped impurity diffusion zones of the same polarity as that of the first impurity diffusion zones; thin-film electrodes each connecting the adjacent one of the fourth impurity diffusion zones and the adjacent one of the second impurity diffusion zones and/or the adjacent one of the third impurity diffusion zones, and isolation zones each provided between the plurality of thin-film electrodes.

Claims

1. A photovoltaic generator comprising:

a substrate;

an insulating layer provided on said substrate;

a plurality of first impurity diffusion zones formed on said insulating layer;

a plurality of second impurity diffusion zones deep enough to reach said insulating layer and of an opposite polarity to that of said first impurity diffusion zones, said second impurity diffusion zones and said first impurity diffusion zones being alternately positioned on the surface of said substrate to form a plurality of substantially vertical pn junctions;

a plurality of third impurity diffusion zones provided on the surface of said first impurity diffusion zones and said second impurity diffusion zones opposite to said insulating layer and of the same polarity as that of said second impurity diffusion zones, one end of each of said third impurity diffusion zones connecting to the adjacent one of said second impurity diffusion zones while the other end connecting to the adjacent one of said first impurity diffusion zones so that the third impurity diffusion zone strides over one of said plurality of vertical pn junctions;

a plurality of fourth impurity diffusion zones formed on the surface of the adjacent one of said first impurity diffusion zones and the adjacent one of said second impurity diffusion zones opposite to said insulating layer and being a heavily doped impurity diffusion zones of the same polarity as that of said first impurity diffusion zones each of said fourth impurity diffusion zones connecting to the adjacent one of said first impurity diffusion zones without contact with the adjacent one of said third impurity diffusion zones that connects to the same one of said first impurity diffusion zones and striding over at most one of said plurality of vertical pn junctions;

a plurality of thin-film electrodes each connecting the adjacent one of said fourth impurity diffusion zones and the adjacent one of said second impurity diffusion zones and/or the adjacent one of said third impurity diffusion zones on the adjacent one of said second impurity diffusion zones; and

a plurality of isolation zones each provided between said plurality of thin-film electrodes.

2. The photovoltaic generator of claim 1, wherein said first impurity diffusion zones are p-type impurity diffusion zones and said second impurity diffusion zones are n-type impurity diffusion zones.

3. The photovoltaic generator of claim 1, wherein said first impurity diffusion zones are n-type impurity diffusion zones and said second impurity diffusion zones are p-type impurity diffusion zones.

4. The photovoltaic generator of claim 1, wherein said second impurity diffusion zones are heavily doped impurity diffusion zones to form ohmic contacts with said thin-film electrodes.

5. The photovoltaic generator of claim 4, wherein said first impurity diffusion zones and said second impurity diffusion zones are alternately positioned in a linear parallel photovoltaic generator array.

6. The photovoltaic generator of claim 1, wherein said second impurity diffusion zones are heavily doped impurity diffusion zones so as to enlarge the thickness of said first impurity diffusion zones and said second impurity diffusion zones in the direction perpendicular to said substrate.

7. The photovoltaic generator of claim 6, wherein said first and said second impurity diffusion zones have a height in the range of 10 to 40 micrometers in the direction perpendicular to said substrate.

8. The photovoltaic generator of claim 6, wherein said first and said second impurity diffusion zones have a height in the range of 10 to 25 micrometers in the direction perpendicular to said substrate.

9. The photovoltaic generator of claim 6, wherein said first and said second impurity diffusion zones have a height in the range of 25 to 40 micrometers in the direction perpendicular to said substrate.

10. The photovoltaic generator of claim 6, wherein said first impurity diffusion zones and said second impurity diffusion zones are alternately positioned in a linear parallel photovoltaic generator array.

11. The photovoltaic generator of claim 1, wherein said first and said second impurity diffusion zones have a height in the range of 10 to 40 micrometers in the direction perpendicular to said substrate.

12. The photovoltaic generator of claim 1, wherein said first and said second impurity diffusion zones have a height in the range of 10 to 25 micrometers in the direction perpendicular to said substrate.

13. The photovoltaic generator of claim 1, wherein said first and said second impurity diffusion zones have a height in the range of 25 to 40 micrometers in the direction perpendicular to said substrate.

14. The photovoltaic generator of claim 1, wherein said first impurity diffusion zones and said second impurity diffusion zones are alternately positioned in a linear parallel photovoltaic generator array.

15. The photovoltaic generator of claim 14, wherein said parallel photovoltaic generator array utilizes the mesa structure formed on the peripheral region as the isolation.

16. The photovoltaic generator of claim 14, wherein said photovoltaic generator is integrated with other electronic devices with the isolation of said other electronic devices achieved by the junction isolation technology.

17. The photovoltaic generator of claim 16, wherein the junctions of said junction isolation technology and the junctions of said second impurity diffusion zones are formed in the same manufacturing step.

18. The photovoltaic generator of claim 1, wherein said photovoltaic generator is integrated with other electronic devices with the isolation of said other electronic devices achieved by the junction isolation technology.

19. The photovoltaic generator of claim 18, wherein the junctions of said junction isolation technology and the junctions of said second impurity diffusion zones are formed in the same manufacturing step.