Ambient and low temperature photoluminescence topography of GaAs substrates, epitaxial and implanted layers.

High resolution photoluminescence topography of GaAs at 300 and 2 K is reported. Topics include lateral homogeneity of semi-insulating substrates, quality of surface polishing, evaluation of sheet carrier concentrations and optimization of implant activations. Spectrally resolved low temperature topography allows images to be generated of carrier temperature and lifetime in substrates and of quantum well thickness variations in heterostructures.