Infrared light scattering and absorption microscopy investigations at dislocations in GaAs crystals

In recent years a number of experiments have been published dealing with the light scattering at small particles. All of these experiments have been made in the visible spectral range. In this paper we report an experimental arrangement for infrared light scattering by dark-field illumination. Preliminary results of the observations of dislocations in GaAs crystals are given. The scattering images are correlated with results obtained by means of absorption microscopy with infrared light. Helix-like fine structures of dislocations are found mainly arranged in the 〈110〉 directions.