Papers by Keyword: Semiconductor Heterostructures

Abstract: An application of compact benchtop X-ray diffractometer for investigation of thin film semiconductor structures was demonstrated. A depth-dependent qualitative phase analysis of multilayer polycrystalline CuInGaSe₂-based solar cell structure was performed. The independent goniometer allowed determination of residual stress values in the molybdenum layer of the solar cell. Grazing-incidence X-ray diffractometry was used to estimate polycrystallinity degree of AlN layers grown by molecular beam epitaxy and correlate it with the growth temperature. X-ray reflectometry measurement were also performed for nucleation AlN layer.

Abstract: Determination of stable phases formed at the Fe/Si interface in (Fe/Si)n structure, grown by thermal evaporation in an ultrahigh vacuum system was performed using conversion electron Mössbauer spectroscopy (CEMS).

Abstract: Partially relaxed III–V heterostructures: GaAs/InGaAs and InP/InAlAs/InGaAs, with a small lattice mismatch, grown using molecular beam epitaxy under compressive or tensile misfit stress at the (001) interface, have been investigated by means of high-resolution X-ray diffractometry, atomic force microscopy and generalized ellipsometry. Additionally, transmission electron microscopy and electron-beam induced current in a scanning electron microscope have been employed to reveal misfit dislocations at the heterostructure interface. Chemical etching was used to determine polarity of the crystals and threading dislocation densities in the epitaxial layers. Our findings are interpreted in terms of the dependent on growth conditions, material’s composition and doping glide velocities of two types of misfit dislocations: α and β, differing in their core structure and lying along two orthogonal 〈110〉 crystallographic directions at the (001) interface.