Silicon carbide films were deposited by plasma enhanced chemical vapor deposition utilizing monomethylsilane (CH3SiH3). Silicon (100) and polycrystalline gold were used as substrates. A mass spectrometric analysis of the monomethylsilane plasma showed that the majority of the Si–C bonds were preserved in the gas phase. The composition, the density and morphology of the amorphous SiC:H (a:SiC:H) films were studied as a function of substrate temperature, composition of the ion flux bombarding the surface and the kinetic energy of these ions. The surface science techniques utilized for these investigations include x-ray photoelectron spectroscopy, Auger electron spectroscopy, scanning electron microscopy, Fourier transform infrared, and Raman spectroscopies.

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A new, simple chemical route was developed for the synthesis of pure nanocalcite crystals by controlling the reaction of an aqueous solution of CaO and CO2 gas. Results revealed formation of well-defined and pure nanocalcite crystals with controlled crystallite and particle size, without additives or organic solvents. The crystallite and particle size can be controlled, and smaller sizes are obtained by decreasing the CaO concentration and increasing the CO2 flow rate. The decrease of crystallite and particle size below a certain threshold provides the nanocalcite crystal signature characteristics that can be clearly observed in XRD patterns, TEM images, FTIR spectra, Raman spectra, XPS spectra, and thermal stability measurements.

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