Optical Interferometry mapping of Si-doped GaAs bulk material

Doping growth inhomogeneities are mapped combining Phase Stepping Microscopy topography with EPIC calibration of the DSL etching rate in Si-doped GaAs. This calibration is applied to doping growth striations, for which only doping fluctuations are producing variation of the etching rate. 3-D maps of the net dopant distributions are obtained for specific DSL etching conditions.