We describe a method to determine the carrier recombination lifetime and surface recombination velocity of semiconductor samples in a single photoconductivity decay measurement. The method is based on the observation of the slope of the photoconductivity signal in the long time scale decay tail in the usual fashion, and, in addition, just after the short laser pulse, which generates the excess carriers. In this article the theory of the measurement and some experimental results on silicon wafers with different surface conditions are presented.
Eränen, S., & Blomberg, M. (1984). Simultaneous measurement of recombination lifetime and surface recombination velocity. Journal of Applied Physics, 56(8), 2372 - 2374. https://doi.org/10.1063/1.334254