Stacked integrated multi-junction solar cell

Patent metadata

Field	Value
Publication number	US-10490683-B2
Application number	US-201514920956-A
Country	US
Kind code	B2
Filing date	Oct 23, 2015
Priority date	Oct 23, 2014
Publication date	Nov 26, 2019
Grant date	Nov 26, 2019

Abstract

A stacked integrated multi-junction solar cell, having a first subcell, whereby the first subcell has a layer of an InGaP compound with a first lattice constant and a first band gap energy, and the thickness of the layer is greater than 100 nm and the layer is formed as part of an emitter and/or as part of the base and/or as part of the space charge region lying between the emitter and base, and a second subcell with a second lattice constant and a second band gap energy, and a third subcell with a third lattice constant and a third band gap energy, and a fourth subcell with a fourth lattice constant and a fourth band gap energy, and a region with a wafer bond is formed between two subcells.

First claim

What is claimed is:

1. A stacked integrated multi-junction solar cell, comprising:
a first subcell having a first layer of an InGaP compound with a first lattice constant (a1) and a first band gap energy (Eg1), a thickness of the first layer being greater than 100 nm, and the first layer being formed as part of an emitter or as part of a base or as part of a space charge region lying between the emitter and the base;
a second subcell having a second layer of an In m P n compound with a second lattice constant (a2) and a second band gap energy (Eg2), a thickness of the second layer being greater than 100 nm and the second layer being formed as part of the emitter or as part of the base or as part of the space charge region lying between the emitter and the base;
a third subcell having a third layer of an In x Ga 1-x As 1-y P y compound with a third lattice constant (a3) and a third band gap energy (Eg3), and a thickness of the third layer being greater than 100 nm and the third layer being formed as part of the emitter or as part of the base or as part of the space charge region lying between the emitter and the base;
a fourth subcell having a fourth layer of an InGaAs compound with a fourth lattice constant (a4) and a fourth band gap energy (Eg4), a thickness of the fourth layer being greater than 100 nm and the fourth layer being formed as part of the emitter or as part of the base or as part of the space charge region lying between the emitter and the base,
wherein Eg1>Eg2>Eg3>Eg4 holds for the band gap energies,
wherein a region with a wafer bond is formed between the first subcell and the second subcell,
wherein the region has a thickness of a maximum of 200 nm,
wherein a lattice constant change in the region is at least 0.01 nm,
wherein the second layer of the second subcell and the third layer of the third subcell are lattice-matched to one another such that a2 is substantially equal to a3,
wherein the third layer of the third subcell and the fourth layer of the fourth subcell are lattice-matched to one another such that a3 is substantially equal to a4,
wherein 1≥m>0.9 and 1≥n>0.8 holds for the stoichiometry of the second layer of the second subcell, and 1>x>0.2 and 1>y>0.1 holds for the stoichiometry of the third layer of the third subcell, and
wherein a first tunnel diode is arranged between the first subcell and the second subcell, a second tunnel diode is arranged between the second subcell and the third subcell, and a third tunnel diode is arranged between the third subcell and the fourth subcell.

2. The multi-junction solar cell according to claim 1 , wherein a substrate is formed from a compound of InP/GaAs/Ge/Si and/or a metal.

3. The multi-junction solar cell according to claim 1 , wherein the thickness of the fourth layer of the fourth subcell is less than 2.2 μm.

4. The multi-junction solar cell according to claim 1 , wherein an optical back mirror is provided, and the optical back mirror comprises a metal compound or a combination of a metal compound and a dielectric layer.

5. The multi-junction solar cell according to claim 1 , wherein the region in which a jump is formed has a thickness of a maximum of 100 nm, and/or the lattice constant in the region makes a jump of at least 0.015 nm.

6. The multi-junction solar cell according to claim 1 , wherein the third layer of the third subcell and the fourth layer of the fourth subcell are lattice-matched to one another and/or a3=a4±Δ2 with Δ2≤0.0015 nm holds for the lattice constants.

7. The multi-junction solar cell according to claim 1 , wherein m>0.95 and n>0.9 holds for the stoichiometry of the second layer of the second subcell, and/or x>0.65 and y>0.3 holds for the stoichiometry of the third layer of the third subcell.

8. The multi-junction solar cell according to claim 1 , wherein the fourth layer of the fourth subcell includes an InGaAsP compound and the phosphorus content in regard to group V elements is greater than 5% and/or less than 30%.

9. The multi-junction solar cell according to claim 1 , wherein a fifth subcell is formed between the first subcell and the wafer bond, wherein the fifth subcell has a fifth layer with a fifth lattice constant and a fifth band gap energy, and a thickness of the fifth layer is greater than 100 nm and the fifth layer is formed as part of the emitter and/or as part of the base and/or as part of the space charge region lying between the emitter and the base, and wherein Eg1>Eg5>Eg2 applies, and wherein a5=a1±Δ3 with Δ3≤0.01 nm holds for the lattice constant.

10. The multi-junction solar cell according to claim 1 , wherein the band gap energy of the first layer of the first subcell is greater than 1.88 eV and the band gap energy of the second layer of the second subcell lies between 1.3 eV and 1.5 eV and the band gap energy of the third layer of the third subcell lies between 0.9 eV and 1.1 eV and the band gap energy of the fourth layer of the fourth subcell lies between 0.6 eV and 0.9 eV.

11. The multi-junction solar cell according to claim 1 , wherein the first layer of the first subcell includes (Al)InGaP, and the second layer of the second subcell includes InP, and the third layer of the third subcell includes InGaAsP, and the fourth layer of the fourth subcell includes InGaAs.

12. The multi-junction solar cell according to claim 9 , wherein the band gap energy of the first layer of the first subcell is greater than 2.0 eV and the band gap energy of the second layer of the second solar subcell lies between 1.2 eV and 1.4 eV and the band gap energy of the third layer of the third subcell lies between 0.9 eV and 1.1 eV and the band gap energy of the fourth layer of the fourth subcell lies between 0.6 eV and 0.9 eV and the band gap energy of the fifth layer of the fifth subcell lies between 1.4 eV and 1.7 eV.

13. The multi-junction solar cell according to claim 1 , wherein the first layer of the first subcell includes AlInGaP, and the second layer of the second subcell includes InP, and the third layer of the third subcell includes InGaAsP, and the fourth layer of the fourth subcell includes InGaAs, and a fifth layer of a fifth subcell includes Al(In)GaAs or InGaAsP.

14. The multi-junction solar cell according to claim 1 , wherein the first layer of the first subcell includes AlInGaP, and the second layer of the second subcell includes InGaAsP, and the third layer of the third subcell includes InGaAsP, and the fourth layer of the fourth subcell includes InGaAs, and a fifth layer of a fifth subcell includes Al(In)GaAs or InGaAsP.

15. The multi-junction solar cell according to claim 1 , wherein the wafer bond is formed between the first subcell and the second subcell and wherein the second layer of the second subcell and the third layer of the third subcell are lattice-matched to one another and a2=a3±Δ1 or a2=a3±Δ2 applies.

16. The multi-junction solar cell according to claim 1 , wherein a superstrate is connected to the first subcell by material bonding and the superstrate comprises a cover glass.

17. The multi-junction solar cell according to claim 3 , wherein a semiconductor mirror or an optical mirror is formed beneath the fourth subcell.

18. The multi-junction solar cell according to claim 3 , wherein a semiconductor mirror or an optical mirror is formed between the third subcell and fourth subcell.

19. The multi-junction solar cell according to claim 1 , wherein a3=a4±Δ1 with Δ1≤0.003 nm and/or a2=a3±Δ1 with Δ1≤0.003 nm.

20. The multi-junction solar cell according to claim 1 , wherein a first substrate of on

Assignees

• Azur Space Solar Power Gmbh

Inventors

• Guter Wolfgang
• Strobl Gerhard
• Dimroth Frank
• Walker Alexandre William

Classifications

• Y02E10/52

  PV systems with concentrators · CPC title

• Y02E10/544

  Solar cells from Group III-V materials · CPC title

• H01L31/0687 Primary

  Electricity · mapped topic

• H01L31/0693

  Electricity · mapped topic

• H10F77/1248

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