High-performance GaInAsSb thermophotovoltaic devices with an AlGaAsSb window
- Lincoln Laboratory, Massachusetts Institute of Technology, Lexington, Massachusetts 02173-9108 (United States)
- Lockheed Martin, Inc., Schenectady, New York 12301-1072 (United States)
A large increase in the quantum efficiency (QE) and open-circuit voltage V{sub oc} of GaInAsSb thermophotovoltaic (TPV) devices is obtained by the use of an AlGaAsSb window layer compared with devices without a window layer. The TPV structure, grown on GaSb substrates by organometallic vapor phase epitaxy or molecular beam epitaxy, consists of a 1-{mu}m-thick n-GaInAsSb base layer, a 3-{mu}m-thick p-GaInAsSb emitter layer, a 100-nm-thick AlGaAsSb window layer, and a 25-nm-thick GaSb contacting layer. The band-gap energy of the lattice-matched GaInAsSb is 0.53{endash}0.55 eV. The peak internal QE of the TPV cells with the window is {gt}90{percent}, compared with less than 60{percent} for those without the window. At a short-circuit current density of {approximately}1000mA/cm{sup 2}, V{sub oc} of {approximately}300meV is obtained for cells with the window layer, compared with less than 220 meV without the window layer. These increases are attributed to a substantial decrease in the surface recombination velocity with the window layer. Based on a standard calculation, the electron diffusion length in the p-GaInAsSb layer is at least 5 {mu}m. {copyright} {ital 1997 American Institute of Physics.}
- OSTI ID:
- 565535
- Journal Information:
- Applied Physics Letters, Journal Name: Applied Physics Letters Journal Issue: 26 Vol. 71; ISSN APPLAB; ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
Similar Records
Lattice-matched epitaxial GaInAsSb/GaSb thermophotovoltaic devices
High-quantum-efficiency 0.5 eV GaInAsSb/GaSb thermophotovoltaic devices