DILUTE NITRIDE BISMIDE SEMICONDUCTOR ALLOYS
High efficiency dilute nitride bismide alloys and multijunction photovoltaic cells incorporating the high efficiency dilute nitride bismide alloys are disclosed. Bismuth-containing dilute nitride subcells exhibit a high efficiency across a broad range of irradiance energies, a high short circuit current density, and a high open circuit voltage.
1 . A multijunction photovoltaic cell comprising a dilute nitride bismide subcell, wherein, the dilute nitride bismide subcell comprises:
Ga 1x In x N y As 1-y-z Bi z , wherein the content values for x, y, and z are within composition ranges as follows: 0.03≦x≦0.19, 0.008≦y≦0.055, and 0.001≦z≦0.09; Ga 1-x In x N y As 1-y-z1-z2 Sb z1 Bi z2 ; wherein the content values for x, y, and z are within composition ranges as follows: 0.03≦x≦0.19, 0.008≦y≦0.055, and 0.001≦z1+z2≦0.09;
GaN y As 1-y-x Bi z , wherein the content values for y and z are within composition ranges as follows: 0.001≦y≦0.055, and 0.001≦z≦0.09; or
GaN y As 1-y-z1-z2 Sb z1 Bi z2 , wherein the content values for y and z are within composition ranges as follows: 0.001≦y≦0.055, and 0.001≦z1+z2≦0.09. and the dilute nitride bismide subcell is characterized by,
an efficiency of at least 70% at an irradiance energy from 1.38 eV to 1.30 eV, and an efficiency of at least 80% at an irradiance energy from 1.38 eV to 1.30 eV;
an efficiency of at least 70% at an irradiance energy from 1.38 eV to 1.18 eV, and an efficiency of at least 80% at an irradiance energy from 1.38 eV to 1.30 eV;
an efficiency of at least 70% at an irradiance energy from 1.38 eV to 1.10 eV, and an efficiency of at least 80% at an irradiance energy from 1.38 eV to 1.18 eV;
an efficiency of at least 70% at an irradiance energy from 1.38 eV to 1.03 eV, and an efficiency of at least 80% at an irradiance energy from 1.38 eV to 1.15 eV;
an efficiency of at least 70% at an irradiance energy from 1.38 eV to 0.99 eV, and an efficiency of at least 80% at an irradiance energy from 1.38 eV to 1.15 eV; or
an efficiency of at least 60% at an irradiance energy from 1.38 eV to 0.92 eV, an efficiency of at least 70% at an irradiance energy from 1.38 eV to 1.03 eV, and an efficiency of at least 80% at an irradiance energy from 1.38 eV to 1.15 eV; wherein
the efficiency is measured at a junction temperature of 25° C.
2 . The multijunction photovoltaic cell of claim 1 , wherein the dilute nitride bismide subcell is characterized by a Eg/q-Voc equal to or greater than 0.55 V measured using a 1 sun AM1.5D spectrum at a junction temperature of 25° C.
3 . The multijunction photovoltaic cell of claim 1 , wherein the dilute nitride bismide subcell is characterized by a Eg/q-Voc from 0.4 V to 0.7 V measured using a 1 sun AM1.5D spectrum at a junction temperature of 25° C.
4 . The multijunction photovoltaic cell of claim 1 , wherein the dilute nitride bismide subcell is characterized by a bandgap within a range from 0.85 eV to 1.25 eV.
5 . The multijunction photovoltaic cell of claim 1 , wherein the dilute nitride bismide subcell is substantially lattice-matched to a GaAs substrate or to a (Sn,Si)Ge substrate.
6 . The multijunction photovoltaic cell of claim 1 , wherein the dilute nitride bismide subcell is p-doped or n-doped.
7 . The multijunction photovoltaic cell of claim 1 , wherein the dilute nitride bismide subcell is characterized by a base thickness of 0.4 micron to 3.5 micron.
8 . The multijunction photovoltaic cell of claim 1 , wherein the multijunction photovoltaic cell comprises at least three subcells.
9 . A photovoltaic module comprising at least one multijunction photovoltaic cell of claim 1 .
10 . A photovoltaic system comprising at least one multijunction photovoltaic cell of claim 1 .
11 . A dilute nitride bismide alloy comprising Ga 1-x In x N y As 1-y-z Bi z , wherein the content values for x, y, and z are within composition ranges as follows: 0.03≦x≦0.19, 0.008≦y≦0.055, and 0.001≦z≦0.09.
12 . A dilute nitride bismide alloy comprising Ga 1-x In x N y As 1-y-z1-z2 Sb z1 Bi z2 ; wherein the content values for x, y, and z are within composition ranges as follows: 0.03≦x≦0.19, 0.008≦y≦0.055, and 0.001≦z1+z2≦0.09.
13 . A dilute nitride bismide alloy comprising GaN y As 1-y-z Bi z , wherein the content values for y and z are within composition ranges as follows: 0.001≦y≦0.055, and 0.001≦z≦0.09.
14 . A dilute nitride bismide alloy comprising GaN y As 1-y-z1-z2 Sb z1 Bi z2 , wherein the content values for y and z are within composition ranges as follows: 0.001≦y≦0.055, and 0.001≦z1+z2≦0.09.
15 . A semiconductor device comprising the dilute nitride bismide alloy of claim 11 .
16 . The semiconductor device of claim 15 , wherein the semiconductor device comprises a photovoltaic cell, a multijunction photovoltaic cell, a laser, a photodiode, a transistor, a photodetector, a power converter, a laser, and an optical amplifier.