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Analysis of the photo voltage decay /PVD/ method for measuring minority carrier lifetimes in P-N junction solar cellsThe photo voltage decay (PVD) method for the measurement of minority carrier lifetimes in P-N junction solar cells with cell thickness comparable to or even less than the minority carrier diffusion length is examined. The method involves the generation of free carriers in the quasi-neutral bulk material by flashes of light and the monitoring of the subsequent decay of the induced open-circuit voltages as the carriers recombine, which is dependent on minority carrier recombination lifetime. It is shown that the voltage versus time curve for an ordinary solar cell (N(+)-P junction) is proportional to the inverse minority carrier lifetime plus a factor expressing the ratio of diffusion length to cell thickness. In the case of an ideal back-surface-field cell (N(+)-P-P(+) junction) however, the slope is directly proportional to the inverse minority carrier lifetime. It is noted that since most BSF cells are not ideal, possessing a sizable back surface recombination velocity, the PVD measurements must be treated with caution and supplemented with other nonstationary methods.
Document ID
19810064894
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Von Roos, O. (California Institute of Technology, Jet Propulsion Laboratory, Pasadena CA, United States)
Date Acquired
August 11, 2013
Publication Date
September 1, 1981
Publication Information
Publication: Journal of Applied Physics
Volume: 52
Subject Category
ENERGY PRODUCTION AND CONVERSION
Distribution Limits
Public
Copyright
Other