Lateral and depth inhomogeneities in Zn-based heterostructures grown on GaAs by MBE

The near-surface morphology, crystalline quality and contamination as well as depth and lateral homogeneity of background impurities and defects distribution in undoped ZnSe and ZnTe films grown by molecular beam epitaxy on GaAs(001) substrates were studied. The improvement of structural quality with the increase of film thickness was observed by X-ray diffraction and atomic force microscope. But sufficient depth inhomogeneity of point and extended defect distribution is present in all films independently on their thickness and increases after deposition of quantum wells. Transversal photovoltage measurements confirm the laminar inhomogeneity of investigated films.