TY - JOUR
T1 - Development and characterization of high-efficiency Ga0.5In0.5P/GaAs/Ge dual- and triple-junction solar cells
AU - Karam, Nasser H.
AU - King, Richard R.
AU - Terence Cavicchi, B.
AU - Krut, Dimitri D.
AU - Ermer, James H.
AU - Haddad, Moran
AU - Cai, Li
AU - Joslin, David E.
AU - Takahashi, Mark
AU - Eldredge, Jack W.
AU - Nishikawa, Warren T.
AU - Lillington, David R.
AU - Keyes, Brian M.
AU - Ahrenkiel, Richard K.
N1 - Funding Information:
solar cells are fabricated on low-cost, high-strength, Ge substrates, making them highly compatible with large-volume manufacturing. DJ solar cell technology has advanced very rapidly, overtaking Si and GaAs single-junction cells, such that DJ cell production has reached a level of 325 kW/year (beginning-of-life, or BOL) at Spectrolab [4]. The average load-point efficiency is over 21.3% for a population of over 470 000 large-area (26.94 cm DJ cells manufactured at Spectrolab. Advances in triple-junction (TJ) GaInP/GaAs/Ge cells with active Ge subcells, fabricated at Spectrolab in a large-scale manufacturing environment, have achieved 26.7% efficiency on large-area (21.65 cm ) cells. Much of the research that resulted in these efficiency improvements at Spec-trolab [5] was made possible by the Multijunction Solar Cell Manufacturing Technology (Mantech) program funded by the USAF and NASA. The success of GaInP/GaAs/Ge DJ and TJ technology depends on the ability to grow these advanced multijunction solar cell structures in high volume by metalorganic vapor phase epitaxy (MOVPE), with precise control over the thickness, composition, and doping level of the deposited films. Understanding the nature of the interfaces in these advanced solar cells [6]–[8] and accurate measurement of their performance characteristics [10] are critical for continued cell improvement.
Funding Information:
Manuscript received January 6, 1999; revised May 26, 1999. This work was supported in part by USAF Philips and Wright Laboratories and by NASA Lewis Research Center under MANTECH Contract F33615-95-C-5561. The review of this paper was arranged by Guest Editor A. Barnett.
PY - 1999
Y1 - 1999
N2 - This paper describes recent progress in the characterization, analysis, and development of high-efficiency, radiation-resistant Ga0.5In0.5P/GaAs/Ge dual-junction (DJ) and triple-junction (TJ) solar cells. DJ cells have rapidly transitioned from the laboratory to full-scale (325 kW/year) production at Spectrolab. Performance data for over 470 000 large-area (26.94 cm2), thin (140 μm) DJ solar cells grown on low-cost, high-strength Ge substrates are shown. Advances in next-generation triple-junction Ga0.5In0.5P/GaAs/Ge cells with an active Ge component cell are discussed, giving efficiencies up to 26.7% (21.65-cm2 area), AM0, at 28°C. Final-to-initial power ratios P/P0 of 0.83 were measured for these n-on-p DJ and TJ cells after irradiation with 1015 1-MeV electrons/cm2. Time-resolved photoluminescence measurements are applied to double heterostructures grown with semiconductor layers and interfaces relevant to these multijunction solar cells, to characterize surface and bulk recombination and guide further device improvements. Dual- and triple-junction Ga0.5In0.5P/GaAs/Ge cells are compared to competing space photovoltaic technologies, and found to offer 60-75% more end-of-life power than high-efficiency Si cells at a nominal array temperature of 60°C.
AB - This paper describes recent progress in the characterization, analysis, and development of high-efficiency, radiation-resistant Ga0.5In0.5P/GaAs/Ge dual-junction (DJ) and triple-junction (TJ) solar cells. DJ cells have rapidly transitioned from the laboratory to full-scale (325 kW/year) production at Spectrolab. Performance data for over 470 000 large-area (26.94 cm2), thin (140 μm) DJ solar cells grown on low-cost, high-strength Ge substrates are shown. Advances in next-generation triple-junction Ga0.5In0.5P/GaAs/Ge cells with an active Ge component cell are discussed, giving efficiencies up to 26.7% (21.65-cm2 area), AM0, at 28°C. Final-to-initial power ratios P/P0 of 0.83 were measured for these n-on-p DJ and TJ cells after irradiation with 1015 1-MeV electrons/cm2. Time-resolved photoluminescence measurements are applied to double heterostructures grown with semiconductor layers and interfaces relevant to these multijunction solar cells, to characterize surface and bulk recombination and guide further device improvements. Dual- and triple-junction Ga0.5In0.5P/GaAs/Ge cells are compared to competing space photovoltaic technologies, and found to offer 60-75% more end-of-life power than high-efficiency Si cells at a nominal array temperature of 60°C.
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U2 - 10.1109/16.792006
DO - 10.1109/16.792006
M3 - Article
AN - SCOPUS:0033323711
VL - 46
SP - 2116
EP - 2125
JO - IEEE Transactions on Electron Devices
JF - IEEE Transactions on Electron Devices
SN - 0018-9383
IS - 10
ER -