An overview was given on recent developments at Fraunhofer ISE in the field of diagnostic techniques based on carrier lifetime measurements. The status of the different lifetime spectroscopy methods and the diagnostic capabilities of infra-red carrier lifetime imaging were outlined. A combination of short acquisition times with high spatial

resolution and high dynamic range under (quasi-)steady-state conditions gives IR lifetime imaging a high potential for the application in material and process characterization. Measuring in the emission mode provided access to the temperature dependence of lifetime and thus spatially resolved temperature dependent lifetime spectroscopy. Images of injection dependent lifetimes may be measured. For the anomalous increase at low injection a modelling description was developed. Assuming carrier trapping as origin of the increase, spatially resolved trap parameter analysis was possible. A new approach to suppress the anomalous increase by the application of sub-bandgap light was demonstrated.

Advanced Defect and Impurity Diagnostics in Silicon Based on Carrier Lifetime Measurements. W.Warta: Physica Status Solidi A, 2006, 203[4], 732-46