Photosensitization of InSb crystals by pulsed laser irradiation

The photosensitization of n-InSb single crystals after irradiation with nan osecond ruby laser pulses was studied. Based on a study of the photoconduct ivity spectra it is established that the surface recombination rate decreas es in the samples subjected to subthreshold irradiation. The steady-state p hotoconductivity, non-equilibrium carrier lifetime and resistivity increase s. Changes in the photo-electric properties of InSb crystals are attributed to the cleaning of the surface and to the gettering of electrically active point defects by extended growth defects. The role of laser-induced stress and shock waves in these processes is discussed. The method for changing t he surface state and modifying the photo-electric parameters of InSb crysta ls and for improving the stability of their properties by means of pulsed l aser irradiation is advanced.