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33rd European Photovoltaic Solar Energy Conference and Exhibition; 911-913, nt spectra of solar cells under harsh measurement conditions without the need of optical windows or moving parts. The small photocurrent, induced by the sequential illumination by a series of LEDs with different emission wavelengths, distributed within the responsivity range of the tested solar cell, is converted to a proportional frequency and then monitored using the audio-card of a personal computer and an appropriate Labview-based Software. Subsequently the quantum yield measurements were performed in-situ during the irradiation of a conventional crystalline Silicon solar cell with 1.7 MeV protons in the spectral range between 400 nm and 880 nm. In this case the complete photocurrent spectrum can been monitored continuously with good temporal resolution.

33rd European Photovoltaic Solar Energy Conference and Exhibition; 811-814, pared, using Liquid Phase Crystallized (LPC) Silicon on glass technology, combined with the use of interdigitated back contacts in order to minimize reflection and shadowing losses. The solar cells have been exposed to a proton beam of 68 MeV, that creates a homogeneous depth profile of defects in the solar cells. A first partial irradiation of the solar cell created a very high local defect concentration and after a strong initial decrease of the short circuit current, the degradation almost saturates. A subsequently homogeneous irradiation of the whole solar cell area – however – resulted in a continuous further degradation of the investigated solar cell. The inhomogeneous defect concentration of the solar cell after this 2-step degradation has been evidenced by LBIC imaging.

24th European Photovoltaic Solar Energy Conference, 21-25 September 2009, Hamburg, Germany; 704-706, Crystalline silicon solar cells using Floating Zone material have been exposed to high energy proton irradiation. In particular the impact of 1.7MeV protons with different fluence values up to 5.1012cm-2 on the currentvoltage characteristics with and without illumination and on the quantum yield characteristics has been investigated. An excellent agreement between experiment data and PC1D simulation has been achieved and allowed us to extract basic parameters device parameter changes due to irradiation. It has been found, that a initial fast degradation is found and a saturation of the proton induced damage is observed for fluence values above 1.1012cm-2. Key degradation parameter is the absorber region minority carrier effective diffusion length.