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Several few µm thick (001)-oriented, metastable MnTe layers with the zinc blende structure grown onto (001)GaAs substrate by MBE during different periods for the last twenty years were investigated by the scanning electron microscopy, atomic force microscopy, X-ray diffraction, and nanoindentation methods. A partial decomposition of the oldest investigated layers was demonstrated. An important decrease of Young's modulus from about 34 GPa to about 17 GPa, resulting from a deterioration of the crystal structure of such layers, was found. [ABSTRACT FROM AUTHOR]

Abstract: The crystalline structure and surface morphology of Dy x O y dielectric films grown on Si substrates were studied by grazing incidence diffraction and absorption with use of synchrotron radiation and by atomic force microscopy. The crystalline structure and the roughness of Dy x O y films were found to be strongly dependent on the deposition rate. The dielectric-silicon interface depends on the type of gas used in the annealing process. Moreover, results from the near edge X-ray absorption studies, have revealed that none of the examined films has a stoichiometry close to the Dy2O3. The level of stoichiometry is determined by the technological conditions. Nevertheless, MOS structures with Dy x O y films (EOT∼23Å) have shown a rather good Dy x O y -Si interface properties, which can be further improve by thermal annealing, and introducing of several additives, therefore Dy x O y films can be considered as suitable candidates for gate dielectric in MOS devices. [Copyright &y& Elsevier]

Cr-based diluted magnetic semiconductors (DMSs) have attracted a lot of attention within the last few years because of their possible applications in the area of spintronics. Modern growth techniques of such materials require efficient methods of characterization of their structure. In this work, the structure of Cr-rich ZnSe layers grown by MBE on (0 0 1) GaAs substrate was investigated by means of the high-resolution X-ray diffraction, atomic force microscopy and Raman scattering. Direct evidence of the mixed Zn1-xCrxSe crystal in the zinc-blende phase is demonstrated by the high resolution X-ray diffraction (a part of Cr is shown to occupy the cationic sites in the crystal lattice). The presence of amorphous or crystalline Se- and Cr-related precipitates in selected samples is demonstrated, their influence on the properties of (Zn,Cr)Se layers is discussed. [Copyright &y& Elsevier]

In this work, the Si+ doping of undoped GaN (n ∼1 × 1016 cm−3) on sapphire by a single step implantation or sequential implantation/recrystallization processes, to a total fluence of 1 × 1016 at/cm2 and subsequent activation annealing at 1100 °C for 2 min, were demonstrated and analysed. We proved that the multicycle implantation/recrystallization process is better in terms of structural and electrical parameters of implanted region than conventional single step implantation. Rutherford backscattering spectrometry in channeling geometry (RBS/c), McChasy simulations and atomic force microscopy (AFM) studies showed, that the proposed process does not deteriorate surface morphoplogy and leads to a significantly lower defect concentrations. Low resistivity ohmic contacts, with R C < 0.1 Ω mm, to low sheet resistivity Si-implanted GaN region (R SH = (36.9 ± 0.7) Ω/sq.), were obtained with the use of sequential implantation with 30 s recrystallization annealing. [ABSTRACT FROM AUTHOR]

We report on the growth of monocrystalline thin films of ZnSe and ZnO by atomic layer epitaxy by simple reaction between elemental precursors. Structural and optical properties of these films are discussed with reference to the investigations performed with atomic force microscopy, scanning electron microscopy, cathodoluminescence and photoluminescence. [Copyright &y& Elsevier]