Al[sub x]Ga[sub 1[minus]x]Sb window layers for InGaAsSb/GaSb thermophotovoltaic cells

Conference · Mon Mar 01 00:00:00 EST 1999 · AIP Conference Proceedings

OSTI ID:6097142

South, Joseph T; Mauk, Michael G; Meakin, John D ^[1]; Mauk, Michael G; Cox, Jeffrey A

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1. Materials Science and Engineering, University of Delaware, Newark, Delaware 19716-2000 (United States)

We report results of a comparative study of AlSb-based window layers for InGaAsSb/GaSb TPV cells made by liquid-phase epitaxy (LPE). Previous work has shown that an AlGaAsSb window layer significantly improves the performance of InGaAsSb/GaSb TPV cells. As expected, the window layer enhances short-wavelength spectral response and increases the open-circuit voltage by reducing the reverse-saturation current of the diode. We present results for a simpler alternative window layer based on the ternary AlGaSb alloy. We fabricated, characterized, and compared InGaAsAsSb TPV of three types: 1. with an AlGaAsSb window layer, 2. with an AlAsSb window layer, and 3. with no window layer. Both [ital p]-on-[ital n] ([ital p]-type InGaAsSb emitter; [ital n]-type InGaAsSb base) and [ital n]-on-[ital p] ([ital n]-type InGaAsSb emitter; [ital p]-type InGaAsSb base) homojunction cell configurations were investigated. The InGaAsSb layers have a [approximately]0.55-ev bandgap and are lattice-matched to a GaSb substrate. As anticipated, both AlGaSb and AlGaAsSb passivated TPV cells were superior to cells without a window layer. The AlGaAsSb/InGaAsSb window/emitter interface is closely lattice matched and would be expected to provide better surface passivation than AlGaSb/InGaAsSb window/emitter interface which has a 0.6[percent] lattice mismatch. On the contrary, our experimental results showed that, based on a comparison of spectral response, AlGaSb window layers were somewhat more effective than AlGaAsSb in passivating the front surface of InGaAsSb diodes. These results demonstrate the viability of a simpler ternary AlGaSb alloy as an alternative to the quaternary AlGaAsSb alloy as a window layer material. [copyright] [ital 1999 American Institute of Physics.]

• DOE Contract Number: FG02-97ER86057
• OSTI ID: 6097142
• Report Number(s): CONF-981055-; CODEN: APCPCS
• Journal Information: AIP Conference Proceedings, Vol. 460:1; Conference: 4. National Renewable Energy Laboratory (NREL) conference on thermophotovoltaic generation of electricity, Denver, CO (United States), 11-14 Oct 1998; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
ALUMINIUM COMPOUNDS
ANTIMONY COMPOUNDS
DIRECT ENERGY CONVERSION
EMISSIVITY
FABRICATION
GALLIUM ARSENIDES
INDIUM ANTIMONIDES
LATTICE PARAMETERS
PASSIVATION
PERFORMANCE
QUATERNARY ALLOY SYSTEMS
SPECTRAL RESPONSE
TERNARY ALLOY SYSTEMS
THERMOPHOTOVOLTAIC CONVERTERS
ALLOY SYSTEMS
ANTIMONIDES
ARSENIC COMPOUNDS
ARSENIDES
CONVERSION
DIRECT ENERGY CONVERTERS
ENERGY CONVERSION
GALLIUM COMPOUNDS
INDIUM COMPOUNDS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
PNICTIDES
SURFACE PROPERTIES
140501* - Solar Energy Conversion- Photovoltaic Conversion
140600 - Solar Energy- Photovoltaic Power Systems