Characterization of solar cells by photocurrent spectroscopy and current-voltage characteristics with high spatial resolution.
Spatially resolved photocurrent-spectroscopy and spatially resolved current-voltage characteristics are introduced as new methods to characterize solar cells. A combination of these two methods is shown to localize and characterize deficiencies and structural damages in processed solar cells with high spatial resolution. The local external and internal quantum efficiencies as well as the local characteristic parameters of the p-n junction like the short circuit current, the saturation current, the ideality factor, and the optically induced shunt resistance can be determined quantitatively. Both, a slab of a damaged and an undamaged (GaIn)(NAs) concentrator solar cell, are used as test structures. Upon these test structures domains with a high concentration of impurities in the crystal structure and structural imperfections in the upper contact region are identified and analyzed. Additional numerical simulations prove the reliability and show limits of the methods.
Schwalm
M
M
Faculty of Physics and Materials Science Center, Philipps-Universität Marburg, Renthof 5 D-35032 Marburg, Germany. michael.schwalm@physik.uni-marburg.de
Lange
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Rühle
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Stolz
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Volz
K
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Chatterjee
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D017097:Electric Impedance; D011211:Electric Power Supplies; D004867:Equipment Design; D019544:Equipment Failure Analysis / Q000379:methods*; D012993:Solar Energy; D013057:Spectrum Analysis / Q000379:methods*