Analysis of photoexcited charge carrier density profiles in Si wafers by using an infrared camera

We demonstrate the mapping of lateral photoexcited charge carrier density profiles in a Si wafer that is illuminated in a spot by strongly absorbed light, using an infrared camera. The radial decay measured for the charge carrier density yields information on the effective carrier lifetime. The lifetime is extracted from the infrared camera image by modeling the transport. The carrier lifetime determined with the infrared camera technique is in accord with results obtained by conventional transient microwave reflectance measurements.