US 9,437,769 B2 · Four-junction quaternary compound solar cell and method thereof

Abstract

A four-junction quaternary compound solar cell and a method thereof are provided. Forming a first subcell (100) with a first band gap, a lattice constant matching with the substrate on an InP grown substrate, forming a second subcell (200) with a second band gap bigger than the first band gap, a lattice constant matching with the substrate on the first subcell, forming a graded buffer layer (600) with a third band gap bigger than the second band gap on the second subcell, forming a third subcell (300) with a fourth band gap bigger than the third band gap, a lattice constant smaller than the substrate on the graded buffer layer, forming a fourth subcell (400) with a fifth band gap bigger than the fourth band gap, a lattice constant matching with the third subcell on the third subcell, and then forming the required four-junction solar cell then by succeeding process including removing the grown substrate, bonding a support substrate, forming electrodes, evaporating an anti-reflect film and so on.

Claims12

Dependent claims

A four-junction quaternary compound solar cell, comprising:

an InP growth substrate;
a first subcell with a first band gap and a lattice constant matched with the substrate lattice that forms on the growth substrate;
a second subcell with a second band gap larger than the first band gap and a lattice constant matched with the substrate lattice that forms on the first subcell;
a graded buffer layer that forms on the second subcell with a third band gap larger than the second band gap;
wherein the lattice constant is gradually reduced in the graded buffer layer formed on the second subcell as the concentration of a component in the graded buffer layer is gradually modified;
a third subcell formed on the graded buffer layer has a fourth band gap larger than the third band gap and a lattice constant less than the lattice constant of the substrate, the first subcell and the second subcell;
and
a fourth subcell formed on the third subcell has a fifth band gap larger than the fourth band gap and a lattice constant matched with the lattice constant of the third subcell.

5 more elements

A four-junction quaternary compound solar cell, comprising:

a supporting substrate;
a first subcell on the supporting substrate with a first band gap;
a second subcell with a second band gap on the first subcell, wherein the second subcell is composed of a quaternary compound InGaAsP emitter region and a base, the second band gap is larger than the first band gap, and a lattice constant of the second subcell is matched with a lattice constant of the first subcell;
a graded buffer layer with a third band gap on the second subcell;
wherein the third band gap is larger than the second band gap, the lattice constant is gradually reduced in the graded buffer layer on the second subcell as the concentration of a component in the graded buffer layer is gradually modified;
a third subcell of a quaternary compound InAlGaAs emitter region and a base with a fourth band gap, on the graded buffer layer, wherein the fourth band gap is larger than the third band gap and a lattice constant of the third subcell is less than the lattice constant of the first and second subcells;
a fourth subcell composed a quaternary compound InAlAsP emitter region and a base with a fifth band gap, on the third subcell, wherein the fifth band gap is larger than the fourth band gap and a lattice constant of the fourth subcell is matched with the lattice constant of the third subcell.

4 more elements

A fabrication method of the four-junction quaternary compound solar cell, comprising the following steps:

providing an InP growth substrate;
forming a first subcell with a first band gap and a lattice constant matched with the substrate lattice on the growth substrate;
forming a second subcell with a second band gap larger than the first band gap and a lattice constant matched with the substrate lattice on the first subcell;
forming a graded buffer layer with a third band gap larger than the second band gap on the second subcell;
and a concentration of a component in the graded buffer layer gradually changes;
forming a third subcell, on the graded buffer layer, wherein the fourth band gap is larger than the third band gap and a lattice constant of the third subcell is less than a lattice constant of the substrate;
and
forming a fourth subcell with a fifth band gap, on the third subcell, wherein the fifth band gap is larger than the fourth band gap and a lattice constant of the fourth subcell is lattice matched with the third subcell.

5 more elements

Dependencies are inferred from the claim text.

Four-junction quaternary compound solar cell and method thereof

Life of this patent

Four-junction quaternary compound solar cell and method thereof

Life of this patent

Abstract

Claims12