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Ge/Si layers are formed on Si/SiO2/Si(100) substrates and are investigated for different growth temperatures. The Si layer is grown by molecular-beam epitaxy, while the Ge layer is produced by the hot wire chemical vapor deposition. Structural studies are carried out using high-resolution transmission electron microscopy and reflection high-energy electron diffraction. Such structures are promising for the growth of high-quality light-emitting structures on them, which are compatible with silicon radiation-resistant integrated circuits. It is shown that a single-crystal Ge layer can be grown on Si/SiO2/Si(100) via a Si buffer layer by the hot wire chemical vapor deposition, and the difficulties arising during the growth of Ge/Si layers on Si/SiO2/Si(100) are demonstrated.

A GaAs/AlAs/GaAs/AlAs/Ge heterostructure grown on a Si/Al2O3(1 $$\bar {1}$$ 02) substrate is formed and studied. The Ge buffer layer is produced by the “hot wire” technique, whereas the III–V layers are grown by metal–organic vapor-phase epitaxy. The optical quality of the III–V layers is determined by photoluminescence spectroscopy. Structural studies are performed by high-resolution transmission electron microscopy. The elemental composition is determined by energy-dispersive X-ray spectroscopy. In the study, the possibility of growing a single-crystal GaAs layer on a Si/Al2O3 substrate through AlAs/GaAs/AlAs/Ge buffer layers is shown.

Synthesis of nanoparticles in insulators attracts tremendous attention due to their unique electrical and optical properties. Here, the gallium (Ga) and gallium nitride (GaN) nanoclusters have been synthesized in the silicon nitride matrix by sequential ion implantation (gallium and nitrogen ions) followed by either furnace annealing (FA) or rapid thermal annealing (RTA). The presence of Ga and GaN nanoclusters has been confirmed by Fourier-transform infrared, Raman and X-ray photoelectron spectroscopy. Thereafter, the effect of RTA and FA on the conduction of charge carriers has been studied for the fabricated devices. It is found from the current–voltage measurements that the carrier transport is controlled by the space charge limited current conduction mechanism, and the observed values of parameter m (trap density and the distribution of localized state) for the FA and RTA devices are ~2 and ~4.1, respectively. This reveals that more defects are formed in the RTA device and that FA provides better performance than RTA from the viewpoint of opto- and nano-electronic applications.

The paper presents an original technique for quantitative analysis of the chemical composition from photoelectron lines obtained by X-ray photoelectron spectroscopy. Despite the simplicity, a proposed algorithm of spectral fit refinement allows one to control the fitting accuracy and to minimize the errors in determining the concentrations of chemical compounds. An obvious advantage of the iterative approach is the automatic convergence to the true spectrum fit form under correct input assumptions and conditions. The validity of the refinement technique is proved by the results of its application in the study of the chemical composition of three types of solid-state structures of nanoelectronics and spintronics. The error decrease in determining the concentration provides revealing new physicochemical features of the phase formation under various methods and parameters of the creation of structures. The discovered dependences of magnetic, electrical and optoelectronic properties on the local composition of nanosystems make it possible to formulate scientifically grounded principles of their development. Due to its simplicity and versatility, the spectral fit refinement technique can be extended to other experimental methods, where mathematical processing of spectral data is required.

—Layers of InAs, InSb, and GaSb semiconductors highly doped with iron during their growth by the method of pulsed laser deposition are studied experimentally. The best temperatures for layer formation on GaAs (100) substrates are: 250°C (InSb : Fe), 300°C (InAs : Fe), and 350°C (GaSb : Fe). At high Fe concentration (over 10 at %) the layers display ferromagnetic properties expressed in emergence of a hysteresis curve within the magnetic field dependences of the Hall resistance, negative magnetoresistance, and in some cases, ferromagnetic-type magnetization at measurements at room temperature. The atoms of iron do not change the type of layer conductivity; InAs : Fe and InSb : Fe layers possess n-type conductivity, and GaSb : Fe layers display p-type conductivity due to their intrinsic point defects.

Nanosized films of stabilized zirconia with Au nanoparticles formed by implanting Au ions are studied by X-ray photoelectron spectroscopy and transmission electron microscopy. The effect of irradiation of films with Au ions and postimplantation annealing on the distribution of chemical elements and zirconium- containing ZrO x compounds over the depth of the films is studied. Based on the data on the dimensional shift of the Au 4 f photoelectron line, the average value of the nanoparticle size is determined.

A new high-precision technique for calculating the ratio of the erythrocyte area/volume using atomic-force microscopy has been developed. The method was tested on erythrocytes of healthy donors. Scanning electron microscopy, atomic-force microscopy, and X-ray microanalysis revealed that magnetite nanoparticles can interact with erythrocyte membranes in vitro. This interaction resulted in the development of a pathology of erythrocytes typical for poikilocytosis and anisocytosis. When the magnetite was incubated with erythrocytes in a serum-free medium, nanoparticles aggregated.

The crystal structure, composition, and magnetic, and electric-transport properties of Mn x Ga y layers deposited onto a GaAs surface by pulsed laser deposition in a hydrogen atmosphere, pulsed laser deposition in vacuum, and electron-beam evaporation in vacuum are investigated. It is shown that the features of each technique affect the composition and crystal structure of the formed layers, and the degree of abruptness and crystalline quality of the heterointerface. Apparently, the composition and crystal structure are responsible for modification of the ferromagnetic properties. The defects in the heterointerface affect the properties of the Mn x Ga y /GaAs diode structure, in particular, the height of the Schottky diode potential barrier.

The technique of X-ray photoelectron spectroscopy combined with ion profiling is used for the quantitative chemical analysis of the structure of spin light-emitting diodes with a GaMnAs spin-injection layer and an InGaAs quantum well. The depth distribution of phases is determined, and the causes of redistribution of the phases are clarified. In the spin-injection layer, the fractions of antiferromagnetic Mn and ferromagnetic MnAs are at the same level. The procedure for phase separation and verification of the correctness of determination of the content of components is improved.

The concentration profiles of species in silicon subjected to gallium and nitrogen co-implantation and subsequent annealing have been investigated by the method of X-ray photoelectron spectroscopy combined with the layer-by-layer ion etching of the implanted layer. It is shown that practically entire implanted gallium undergoes out-diffusion, but the preliminary implantation of nitrogen for the synthesis of a barrier SiNx layer makes it possible to avoid the essential loss of gallium. In this case, about 14 % of implanted gallium bond to nitrogen. The obtained data are discussed from the viewpoint of the possibility of ion synthesis of GaN inclusions in silicon matrix.