Minority charge carrier lifetime mapping of crystalline silicon wafers by time-resolved photoluminescence imaging

A camera-based method to record spatially and time-resolved photoluminescence images of crystalline silicon wafers was developed. The camera signal is modulated by a rotating shutter wheel, allowing for a wide range of camera types to be used for the measurement and easy integration into existing photoluminescence setups. The temporal resolution is sufficient to record the decay curve of photoexcited charge carriers in surface-passivated silicon wafers. A transient measurement of minority carrier lifetimes down to less than 10 mu s can be obtained for each pixel individually, without the need for any external calibration. (C) 2011 American Institute of Physics. [doi:10.1063/1.3630031]