CHEMICAL STRUCTURE AND FUNCTIONAL PROPERTIES OF AMORPHOUS BORON CARBONITRIDE FILMS

Journal of Structural Chemistry - We report a comprehensive study of the effect of the chemical structure of boron carbonitride films on the variability of their functional characteristics. The...     

Synthesis of Highly Transparent SiCxNyOz:H Films via Plasma-Chemical Decomposition of 1,1,3,3,5,5-Hexamethylcyclotrisilazane,Oxygen, and Nitrogen Gas Mixture

Russian Journal of General Chemistry - Synthesis of silicon oxycarbonitride films highly transparent over a wide spectral region (350–2500 nm) has been developed. The films have been...     

Chemical composition and properties of films produced from hexamethyldisilazane by plasma-enhanced chemical vapor deposition

Relationships between the chemical composition of the gas phase and the properties of SiC_xN_yH_z films produced from hexamethyldisilazane by plasma-enhanced chemical vapor deposition have been studied. The plasma composition has been examined by optical emission spectroscopy. Thermal analysis of the films with simultaneous mass spectrometric detection of released gases has been performed. On the basis of the results and published data, mechanisms for the formation of films by plasma polymerization have been proposed and the film growth at a low plasma power and high reactor temperatures has been found to follow the heterogeneous mechanism.     

Features of determination of thickness of dielectric films obtained in searching experiments

The approach to determination of the thickness and the refractive indices of dielectric films obtained in searching experiments is discussed. Experiments of this kind often exhibit unpredictable values of thickness and refractive indices of films. Nondestructive noncontact methods of spectrophotometry and ellipsometry not involving preliminary preparation of samples are applied. The approach to determination of the thickness and the refractive indices of films is illustrated by means of samples of silicon carbonitride films obtained on silicon substrates by plasma-chemical decomposition of gas-phase trimethyl(phenylamino)silane.     

Optical and mechanical properties of films obtained by plasma decomposition of hexamethyldisilazane

Films of SiC _x N _y H _z composition are obtained by chemical deposition from the vapor phase via the activation of high-frequency discharge plasma (PECVD). The organosilicon compound hexamethyldisilazane, which contains all the atoms needed for the formation of films, is used as our initial material. Physicochemical properties of the films are studied by spectroscopy of surface acoustic waves, measuring the bending of a film-substrate system, ellipsometry, and infrared spectroscopy. Important features of the films?? structure are established. It is shown that at temperatures of deposition below 400°C, films contain chemical bonds of an organic nature, have very low values of density and the Young modulus, and exhibit high levels of elasticity, indicating their polymer-like structure. It is established that at higher temperatures of deposition, films are inorganic composite materials.     

Temperature dependences of the optical properties and the phase composition of vanadium dioxide films obtained by chemical vapor deposition

By low pressure chemical vapor deposition single-phase vanadium dioxide films containing monoclinic phase M1from vanadyl acetylacetonate vapor are obtained on monocrystalline silicon Si(100) substrates. Changes in the phase composition of the films on heating to 90 °C are studied by X-ray diffraction. It is found that in the temperature range 60-70 °C the monoclinic phase passes into tetragonal R. At higher temperatures only the tetragonal phase is observed. By reflection spectrophotometry and ellipsometry the temperature dependences of the optical properties of the films exhibiting hysteresis are determined. At wavelengths less than 600 nm the reflection spectra are almost insensitive to temperature variation. After the linear normalization the reflection and extinction coefficients are well consistent with changes in the phase composition.     

Structure and elemental composition of transparent nanocomposite silicon oxycarbonitride films

Based on thermodynamic simulation on the deposition of condensed phases with the complex composition in the Si–C–N–O–H system in a wide temperature range, using initial gas mixtures of 1,1,3,3-tetramethyldisilazane (HSi(CH₃)₂)₂NH (TMDS), TMDS with a variable mixture of oxygen and nitrogen (O₂+xN₂), a method is developed to obtain SiC _x N _y O _z :H nanocomposite films by the plasma chemical decomposition of this gas mixture in the temperature range of 373-973 K. By FTIR and energy dispersive X-ray spectroscopy the structure of chemical bonds and the elemental composition of the obtained silicon oxycarbonitride films are studied. The in situ composition of the initial gas phase in PECVD processes is examined by optical emission spectroscopy.