Contactless measurement of minority carrier lifetime in silicon ingots and bricks



Measuring the bulk lifetime of unpassivated blocks and ingots is of great interest to the solar cell industry. The eddy-current photoconductance method is a common choice for such measurements, employing the quasi-steady-state (QSS) mode for lower lifetime samples, and the transient photoconductance decay (PCD) mode for higher lifetime samples. Due to the high surface recombination velocity in unpassivated bulk samples, the lifetime measured with this method consists of components of recombination at both the surface and in the bulk. In order to determine the bulk lifetime from the measurement data, simulations of both transient and QSS mode measurements were conducted. Copyright © 2010 John Wiley & Sons, Ltd.