Lattice matchable alloy for solar cells
AssigneeSolar Junction Corporation
InventorsREBECCA ELIZABETH JONES-ALBERTUS, HOMAN BERNARD YUEN, TING LlU, PRANOB MISRA
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Abstract
An alloy composition for a subcell of a solar cell is provided that has a bandgap of at least 0.9 eV, namely, Ga1-xInxNyAs1-y-zSbz with a low antimony (Sb) content and with enhanced indium (In) content and enhanced nitrogen (N) content, achieving substantial lattice matching to GaAs and Ge substrates and providing both high short circuit currents and high open circuit voltages in GaInNAsSb subcells for multijunction solar cells. The composition ranges for Ga1-xInxNyAs1-y-zSbz are 0.07≦x≦0.18, 0.025≦y≦0.04 and 0.001≦z≦0.03.
Claims10
A multijunction solar cell comprising:
- a first subcell comprising Ga1-xInxNyAs1-y-zSbz, wherein,
- the content levels are selected to achieve a bandgap from 0.9 eV to 1.1 eV;
- the content values for x, y, and z are within composition ranges as follows:
- 0.07≦x≦0.18, 0.025≦y≦0.04 and 0.001≦z≦0.03;
- the first subcell is characterized by a short circuit current Jsc greater than 13 mA/cm2 and an open circuit voltage Voc greater than 0.3 V when illuminated with a filtered 1 sun AM1.5D spectrum in which all light having an energy greater than the bandgap of GaAs is blocked;
- and
- at least one second subcell overlying the first subcell to form the multijunction solar cell.
A multijunction solar cell comprising:
- a substrate selected from Ge and GaAs;
- a first subcell overlying the substrate, wherein the first subcell comprises a base comprising Ga1-xInxNyAs1-y-zSbz, wherein,
- the content levels are selected to achieve a bandgap from 0.9 eV to 1.1 eV;
- the content values for x, y, and z are within composition ranges as follows:
- 0.07≦x≦0.18, 0.025≦y≦0.04 and 0.001≦z≦0.03;
- the first subcell is characterized by a short circuit current Jsc greater than 13 mA/cm2 and an open circuit voltage Voc greater than 0.3 V when illuminated with a filtered 1 sun AM1.5D spectrum in which all light having an energy greater than the bandgap of GaAs is blocked;
- the first subcell is substantially lattice matched to the substrate;
- the first subcell is characterized by a thickness greater than 1 μm;
- and
- at least one second subcell overlying the first subcell.
Dependencies are inferred from the claim text.