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Abstract: Si- and Cr-containing C films were deposited by magnetron sputtering combined with CVD onto silicon wafers. The composition and chemical structure were characterized by X-ray Photoelectron Spectroscopy (XPS) and nanomechanical properties by depth-sensing hardness and scratch techniques. The incorporated Si and Cr are preferentially bonded to carbon, in accordance with simplified thermodynamic calculations and as manifested by the XPS chemical shifts. At relatively high Cr- and low Si-content silicides (Cr x Si) may also form as indicated by X-ray induced Auger electron spectroscopy. The chromium content in the C–Si–Cr films varied between 1 and 55at% while the silicon content in the same films between 25 and 0at%. For comparison two-component films of Si–C and Cr–C were also deposited with Si-content up to 42at% and Cr-content up to 55at% by varying the input power of the magnetrons. The nanohardness (H) and reduced modulus (E) were higher for all the films than that of the silicon substrate being 10GPa, 127GPa, respectively. Interestingly, the H and E of the three-component CrSiC films were almost invariant of the changes of the components'' concentration within the indicated range and varied between 13–16GPa and 120–140GPa. H and E values for the two-component Cr–C films were much higher, reaching about 22GPa and 170GPa, respectively. [Copyright &y& Elsevier]

Abstract: A simple thermal chemical vapor deposition technique is employed for the pyrolysis of a natural precursor “camphor” and deposition of carbon films on alumina substrate at higher temperatures (600–900°C). X-ray diffraction measurement reveals the amorphous structure of these films. The carbon films properties are found to significantly vary with the deposition temperatures. At higher deposition temperature, films have shown predominately sp2-bonded carbon and therefore, higher conductivity and lower optical band gap (Tauc gap). These amorphous carbon (a-C) films are also characterized with Raman and X-ray photoelectron spectroscopy. In addition, electrical and optical properties are measured. The thermoelectric measurement shows these as-grown a-C films are p-type in nature. [Copyright &y& Elsevier]