Evaluation of effective carrier lifetime of CdTe solar cells using transient photovoltage decay measurements

A transient photovoltage decay (TPVD) measurement system is currently being developed at CREST and measurements were conducted on several CdTe solar cells. The extracted effective carrier lifetimes were around 100ns. The effect of external illumination biasing was investigated and was found to reduce the effect of junction capacitance and saturate trap states in the devices. This resulted in shorter extracted effective carrier lifetimes. Increasing the illumination of the pulsed-laser intensity also increased the effective carrier lifetime.