Growth studies at bulk III-Vs by image processing

The patterns of inhomogeneities in GaAs and InP are studied by scattering and diffraction of light. An adapted version of laser scattering tomography is used for observations with short exposure times and large fields. The information about the three-dimensional distribution of the scatterers in GaAs are evaluated by video travels through the crystal and images of intensities added in interesting directions. Near-infrared transmission and striation distance mapping act like special data compression techniques due to their optical principles. In general, columnar extension of cellular patterns and striations could not be detected in s.i. GaAs. Long-range correlations exist for lineages and slip lines. The comparison with the behavior of striations in doped InP cannot confirm the idea that cellular patterns in GaAs originate from constitutional supercooling during solidification.