Method of fabricating multijunction solar cell assembly for space applications

Patent metadata

Field	Value
Publication number	US-10818812-B2
Application number	US-201916543833-A
Country	US
Kind code	B2
Filing date	Aug 19, 2019
Priority date	Oct 19, 2015
Publication date	Oct 27, 2020
Grant date	Oct 27, 2020

Abstract

A multijunction solar cell assembly and its method of manufacture including first and second discrete and different semiconductor body subassemblies which are electrically interconnected to form a five junction solar cell, each semiconductor body subassembly including first, second, third and fourth lattice matched subcells; wherein the average band gap of all four cells in each subassembly is greater than 1.44 eV.

First claim

The invention claimed is:

1. A method of forming a solar cell assembly comprising at least a five junction solar cell and including a terminal of first polarity and a terminal of second polarity, the method comprising:
providing first and second semiconductor bodies, each including an identical tandem vertical stack of at least an upper first, a second and a third solar subcells, a bottom solar subcell, and a blocking p-n diode or insulating layer disposed between the third solar subcell and the bottom solar subcell, wherein the upper first, second and third solar subcells in the first semiconductor body are electrically connected in series with one another, and wherein the upper first, second and third solar subcells in the second semiconductor body are electrically connected in series with one another;
mounting the second semiconductor body adjacent to the first semiconductor body;
providing a bottom contact on the bottom solar subcell of the second semiconductor body;
connecting the bottom contact on the bottom solar subcell of the second semiconductor body to the terminal of the second polarity;
connecting the third solar subcell of the first semiconductor body in a series electrical circuit with the third solar subcell of the second semiconductor body;
connecting the third solar subcell of the first semiconductor body in a series electrical circuit with the bottom solar subcell of the first semiconductor body;
connecting the bottom solar subcell of the first semiconductor body in a series electrical circuit with the bottom solar subcell of the second semiconductor body; and
providing a top electric contact on the upper first solar subcell of each of the first and second semiconductor bodies and electrically connecting each of the top electrical contacts to the terminal of the first polarity.

2. The method of claim 1 further including partially exposing one or more layers in at least one of the first or second semiconductor bodies to provide access to the one or more layers for electrically conductive interconnects.

3. The method of claim 2 wherein partially exposing one or more layers in at least one of the first or second semiconductor bodies includes etching from a top surface of at least one of the first or second semiconductor bodies.

4. The method of claim 1 further including etching from a respective top surface of each of the first and second semiconductor bodies so as to partially expose layers in each of the first and second semiconductor bodies.

5. The method of claim 4 including connecting different ones of the partially exposed layers to one another by electrically conductive interconnections to form the series electrical circuits.

6. The method of claim 1 including growing semiconductor layers for each of the first and second semiconductor bodies, wherein each of the solar subcells of the first and second semiconductor bodies includes a respective junction formed of p type and n type regions of semiconductor material.

7. The method of claim 1 wherein the blocking p-n diode or insulating layer of each of the first and second semiconductor bodies is disposed between respective first and second lateral conduction layers in the respective semiconductor body.

8. A method of forming a solar cell assembly including a terminal of first polarity and a terminal of second polarity comprising:
providing first and second semiconductor bodies, each including an identical tandem vertical stack of at least an upper first, a second and a third solar subcells, a bottom solar subcell, and a blocking p-n diode or insulating layer disposed between the third solar subcell and the bottom solar subcell, wherein the upper first, second and third solar subcells in the first semiconductor body are electrically connected in series with one another, and wherein the upper first, second and third solar subcells in the second semiconductor body are electrically connected in series with one another, and wherein the blocking p-n diode or insulating layer of each of the first and second semiconductor bodies is disposed between respective first and second lateral conduction layers in the respective semiconductor body;
mounting the second semiconductor body adjacent to the first semiconductor body;
providing a bottom contact on the bottom solar subcell of the second semiconductor body;
connecting the bottom contact on the bottom solar subcell of the second semiconductor body to the terminal of the second polarity;
connecting the third solar subcell of the first semiconductor body in a series electrical circuit with the third solar subcell of the second semiconductor body; and
providing a top electric contact on the upper first solar subcell of each of the first and second semiconductor bodies and electrically connecting each of the top electrical contacts to the terminal of the first polarity.

9. The method of claim 8 further including:
etching from a respective top surface of each of the first and second semiconductor bodies so as to partially expose layers in each of the first and second semiconductor bodies; and
connecting different ones of the partially exposed layers to one another by electrically conductive interconnections to form the series electrical circuit.

10. The method of claim 8 further including:
partially exposing layers in each of the first and second semiconductor bodies; and
connecting different ones of the partially exposed layers to one another by electrically conductive interconnections to form the series electrical circuit.

11. The method of claim 10 wherein connecting different ones of the partially exposed layers to one another by electrically conductive interconnections further includes connecting the third solar subcell of the first semiconductor body in a series electrical circuit with the bottom solar subcell of the first semiconductor body.

12. The method of claim 10 wherein connecting different ones of the partially exposed layers to one another by electrically conductive interconnections further includes connecting the bottom solar subcell of the first semiconductor body in a series electrical circuit with the bottom solar subcell of the second semiconductor body.

13. The method of claim 12 wherein connecting the bottom solar subcell of the first semiconductor body in a series electrical circuit with the bottom solar subcell of the second semiconductor body includes electrically connecting the bottom solar subcell of the first semiconductor body to one of the lateral conduction layers in the second semiconductor body.

14. The method of claim 8 further including connecting the third solar subcell of the first semiconductor body in a series electrical circuit with the bottom solar subcell of the first semiconductor body.

15. The method of claim 14 wherein connecting the third solar subcell of the first semiconductor body in a series electrical circuit with the bottom solar subcell of the first semiconductor body includes electrically connecting the first and second lateral conduction layers of the first semiconductor body to one another.

16. The method of claim 8 wherein connecting the third subcell of the first semiconductor body in a series electrical circuit with the third subcell of the second semiconductor body includes electrically connecting one of the lateral conduction layers in the first semiconductor body with one of the lateral conduction layers in the second semiconductor body.

Assignees

• Solaero Tech Corp

Inventors

• Derkacs Daniel
• Steinfeldt Jeffrey

Classifications

• H10F77/1248

  having three or more elements, e.g. GaAlAs, InGaAs or InGaAsP · CPC title

• H10F71/1272

  comprising at least three elements, e.g. GaAlAs or InGaAsP · CPC title

• H10F19/902

  for series or parallel connection of photovoltaic cells · CPC title

• H10F10/142 Primary

  comprising multiple PN homojunctions, e.g. tandem cells · CPC title

• H10F10/161 Primary

  comprising multiple PN heterojunctions, e.g. tandem cells · CPC title