Whitepapers & Technical Articles

Qualification and Production of SolAero ZTJ Solar Panels for Space Missions

SolAero’s latest generation InGaP/InGaAs/Ge ZTJ triple-junction space-grade high-efficiency solar cells have been in volume production since 2009, with over 300,000 flight cells produced to power more than 35 separate satellites. The ZTJ cells, CICs (Coverglass-Interconnected-Cell) and solar panels have also been characterized and qualified to both the AIAA-S-111 and AIAA-S-112 standards. More than 10 life-cycle […]
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Array Design Considerations for the Solar Probe Plus Mission

The NASA Solar Probe Plus (SPP) mission will fly into and study the Sun’s corona, reaching as close as 8.5 solar radii from the surface of the Sun. Power generation for the spacecraft will be provided by two solar array wings, which are being designed and built by Johns Hopkins University Applied Physics Laboratory and […]
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Evolution of a 2.05 eV AlGaInP Top Sub-cell for 5 and 6J-IMM Applications

This paper discusses the evolution of our 2.05 eV AlGaInP top sub-cell. Although we were not successful in introducing a more optimum 1.94 eV AlGaInP alloy into the top sub-cell of our 3 or 4J-IMM (inverted metamorphic multijunction) structure because of insufficient current density capacity, we did successfully develop a 2.05 eV AlGaInP top subcell […]
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Experimental Results from Performance Improvement and Radiation Hardening of Inverted Metamorphic Multi-Junction Solar Cell

This paper discusses results from continued development of Inverted Metamorphic Multi-junction (IMM) solar cells with air mass zero (AM0) conversion efficiencies greater than 34%. An experimental best four-junction IMM (IMM4J) design is presented. In an effort to improve IMM performance in space radiation environments, 1-MeV electron irradiation studies are conducted on the individual IMM4J subcells. […]
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Analysis of Performance Goals for III/V on Active Si Concentrator Solar Cells

A primary goal of terrestrial photovoltaics is to reach grid cost parity. This is a difficult task, largely due to the seemingly inverse relationship between efficiency and cost. Multi-junction III/V solar cells on an active Si substrate may break this relationship by providing high efficiency with much lower material cost than traditional concentrator solar cells. […]
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UV Exposure Experiments for Solar Probe Plus Array

NASA’s Solar Probe Plus (SPP) will travel closer to the Sun than any previous spacecraft. During its 7-year, 24-orbit mission, SPP will make scientific measurements of the solar corona, reaching minimum perihelion at ~9.5 solar radii (Rs) from the center of the Sun. The solar array wings powering the spacecraft will operate under wide-ranging temperature […]
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Performance and Radiation Resistance of Quantum Dot Multi-Junction Solar Cells

Lattice matched, triple-junction solar cells with strain compensated quantum dots (QDs) in the GaAs middle cell were grown by Metal-Organic Chemical Vapor Deposition (MOCVD). Devices with different numbers of QD layers are compared to baseline devices with no QDs. Quantum efficiency and light I-V measurements show an increase in short circuit current density and degradation […]
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