Testing of solar cells using fast transients

conference paper

English

In solar cell diagnostic the parameters as the reverse breakdown voltage, depletion layer width and capacitance, serial and parallel resistance and lifetime of minority carriers are of great importance. To measure electric parameters standard method for measurement of substitute scheme can be used except measurement of reverse breakdown voltage because of large reverse current by some cells. Minority carrier lifetime estimation is more complicated. In fact there are few methods for measurement of minority carriers lifetime on unprocessed substrate, but this methods are not applicable easily on solar cells. Characterization of solar cells based on evaluation of solar cell response to fast transients is described. The measurement and evaluation procedure is very simple and no expensive devices are needed. Estimating the recombination time there is a problem with influence of the depletion layer capacitance, which masks the recombination phenomena. Because relatively high doping level by standard silicon solar cells to cancel the influence of the depletion layer capacitance a voltage bias in the range 400 – 500 mV is needed. The voltage bias was made with dark current bias or with light bias. The measurement and evaluation scheme is given and some results acquired by testing of different quality solar cells are discussed.

Crystalline Silicon Solar Cells; Lifetime of minority carriers; Breakdown Voltage

J.Bousek, A. Poruba

2006

4. 9. 2006

3-936338-20-5

21st European Photovoltaic Solar Energy Conference

253

258

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