Role of an inert component in compositions with manganese(II) and manganese(IV) oxides in studying nonlinear effects in GaAs thermal oxidation

GaAs thermal oxidation by mixtures containing manganese(II) and manganese(IV) oxides and gallium arsenide-inert components was studied.     

Synthesis and Magnetic Characteristics of Neodymium Ferrite Powders with Perovskite Structure

Russian Journal of Applied Chemistry - Nanopowders of neodymium ferrite with perovskite structure were synthesized by co-precipitation precipitation via hydrolysis of iron(III) and neodymium(III)...     

Analysis of the optical and structural properties of oxide films on InP using spectroscopic ellipsometry

The optical properties of oxide films grown on InP with the aid of various procedures are studied using spectroscopic ellipsometry. Methodological approaches and techniques for the interpretation of the results of the ellipsometric measurements are analyzed. It is demonstrated that the films resulting from the oxidation of the structures with the magnetron-sputtered chemostimulator exhibit relatively low absorption, normal dispersion of the refractive index, and sharp interfaces. As distinct from such films, the films that result from the oxidation of InP with active centers created by the explosion of a vanadium wire or deposition of chemostimulator from sol or gel exhibit strong absorption bands over the entire spectral range and substantial dispersion of optical properties in the interface regions. The applicability limits for the express diagnostics of the films based on the measurements using a single-wavelength laser ellipsometer are determined.     

Synthesis and Magnetic Properties of Barium-Doped Nanocrystal Lanthanum Orthoferrite

Russian Journal of General Chemistry - Barium-doped nanocrystalline lanthanum ferrite was synthesized by the method of co-precipitation and subsequent annealing at 1000°C. The maximum degree...     

Effect of inert components (Y2O3, Al2O3, and Ga2O3) on the chemistimulating effect of the Sb2O3 activator of GaAs thermal oxidation

Chemistimilated thermal oxidation of gallium arsenide was studied using Sb₂O₃ activator oxide in compositions with Ga₂O₃, Al₂O₃, and Y₂O₃ inert components. For Sb₂O₃-Y₂O₃ compositions, the thickness of the resulting oxide layer on GaAs was found to be a linear function of composition over the enter range of the compositions. For antimony oxide compositions with Ga₂O₃ and Al₂O₃ inert components, nonadditivities were observed near the component ordinates. For the Sb₂O₃-Ga₂O₃ system, the chemistimulating efficiency noticeably weakened at low concentrations of the inert component. The linear trend observed for this system within 0–60 mol % Sb₂O₃ is additively determined by the oxide layer thickness on GaAs in the presence of Sb₂O₃ and in the absence of activator. In the presence of inert Al₂O₃, the chemistimulating effect was enhanced near the Al₂O₃ ordinate and the resulting function was nonadditive with respect to the thicknesses reached in the presence of the individual components.     

Effect of different types of annealing on the thermal oxidation of V x O y /InP structures formed by the deposition of vanadium(V) oxide gel on the phase composition and morphology of films

The effect of different types of annealing (thermal or pulsed photon) of V _x O _y /InP structures synthesized using vanadium pentoxide gel on the process of their thermal oxidation, and the phase composition and morphology of the films are studied by the methods of X-ray phase analysis (XRD), Auger electron spectroscopy (AES), and scanning tunneling microscopy (STM). Thermal annealing makes it possible to synthesize films with a smoother surface relief in the absence of film-substrate interaction before thermal oxidation. Pulsed photon treatment compared with thermal annealing leads to more effective and rapid crystallization of the amorphous phase of the V₂O₅ gel and faster growth of oxide films during the thermal oxidation of V _x O _y /InP structures. As a result, pulsed photon treatment leads to the formation of InVO₄ as a product of the interaction between the semiconductor substrate and the chemostimulator, which is an attribute of the “hard” methods of chemostimulator deposition, i.e., magnetron sputtering and electric explosion of the conductor.     

Nonadditive Linearity in the Chemostimulating Effect of Activator Oxides + Dlient Compositions on GaAs Thermal Oxidation

The chemostimulation efficiency of the activators Sb₂O₃ and Bi₂O₃ in compositions with a diluent (Al₂O₃) is a linear function of activator percentage over a wide range of temperatures. This function is not, however, additive to the thicknesses achieved in the presence of individual components. The percentage of the activator elements in the resulting oxide layers coincides with that in the initial compositions in the linear region and differs from it in the nonadditivity region. Thermal analysis in combination with X-ray powder diffraction showed that Al₂O₃ alters the temperature range and character of the intrinsic transformations of activator oxides.