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Efficient hydrogenated diamond-like carbon (DLC) film deposition in a plasma reactor that features both the capacitive and inductively coupled operation regimes is reported. The hydrogenated DLC films have been prepared on silicon wafers using a low-frequency (500 kHz) inductively coupled plasma (LF ICP) chemical vapor deposition (CVD) system. At low RF powers, the system operates as an asymmetric capacitively coupled plasma source, and the film deposition process is undertaken in the electrostatic (E) discharge regime. The films deposited in the electrostatic mode feature graphite-like structure. Above the mode transition threshold, the high-density inductively coupled plasma is produced in the electromagnetic (H) discharge regime. Raman spectrometry suggests the possibility to control relative proportions of sp² and sp³ hybridized carbon. Variation of the DC substrate bias results in dramatic modification of the film structure from the polymeric (unbiased substrates) to the diamond-like (optimized bias). It has been shown that the deposition rate and hardness of the DLC film are much higher in the H-mode deposition regime. For a 20 mTorr H-mode CH[sub 4]+Ar gas mixture discharge, the DLC film exhibits mechanical hardness of 18 GPa, Young's modulus of 170 GPa, and compressive stress of 1. [ABSTRACT FROM AUTHOR]

Ta-C and iron containing amorphous carbon (a-C:Fe) films were deposited by filtered cathodic vacuum arc technique. The influences of Fe contents on the wettability of the films were investigated in terms of surface energy. The surface energy of a-C:Fe films was determined by the contact angle measurement. Atomic force microscopy (AFM), Raman spectroscopy and X-ray induced photoelectron spectroscopy (XPS) were employed to analyze the origin of the variation of surface energy with various Fe content. It is found that the contact angle for water increases significantly after incorporating Fe into the films and the films become hydrophobic. The roughness of these films has a little effect on the contact angle. The surface energy is reduced after incorporating Fe into the a-C film which is due to the reduction of both dispersive and polar component. The reduction in dispersive component is ascribed to the decrease of atomic density of the a-C:Fe films due to the increase in sp² bonded carbon. The absorption of oxygen on the surface play an important role in the reduction of polar component for the a-C:Fe films. It is proposed that such network as (C[sub n]-O-Fe)-O-(Fe-O-C[sub n]) may be formed and responsible for the reduction of polar component. [ABSTRACT FROM AUTHOR]

Amorphous silicon-carbon alloy films have been successfully deposited by filtered cathodic vacuum arc technique. The structural and mechanical properties of the films were investigated by using x-ray photoelectron spectroscopy (XPS), Raman spectroscopy, surface profiler and nano-indenter. The silicon content in the films determined by XPS measurement varies from 2.4 to 48 at.%. Both XPS and Raman spectroscopy show the existence of silicon carbide dusters in the films containing intermediate concentration of silicon. The silicon atoms predominately substitute the carbon atom into the carbon clusters at low silicon concentration, and form amorphous silicon carbide clusters or amorphous silicon clusters at high silicon concentration. The hardness of the films varies from 60 to 22 GPa while the stress reduces from 8.0 to 2.1 GPa. [ABSTRACT FROM AUTHOR]

A solution process was used to grow SrTiO3 (STO) buffer layers on LaAlO3 (LAO) and biaxially textured Ni substrates by spin coating technique. The epitaxial STO film obtained has strong cube texture and uniform microstructure. A metal organic decomposition process using trifluoroacetate precursors was applied to deposit YBa2Cu3O7-δ (YBCO) thin films on these buffer layers. The YBCO/STO/LAO was biaxially textured and the TConset and ΔTC is 90.1K and 2.7K, respectively. [ABSTRACT FROM AUTHOR]