Plasma film variables

Plasma Synthesis The use of plasma methods has lead to a new range of materials having unique properties. An example is the family of amorphous elemental hydrides (eg cr-C H Of -Si H or-P H) which contain a variable proportion of H from almost zero to 50 atomic %. The carbon films, known variously as "hard carbon", "diamond-like carbon", " a-carbon" etc (9 ) - These layers are of considerable interest because of their optical and abrasion-resistant properties etc (Table I). The properties of these Gr-carbon films, can be tailored by modifying the plasma parameters. 

Figure 19. Configuration for experimental reflectivity measurements on a film using a fixed or variable wavelength light source. The film thickness (d) is indicated as well as the refractive indices of the plasma (n ), film (nx), and substrate Oii)-...

A GS-MS method for the analysis of etodolac in human plasma has been developed [16]. Plasma samples were spiked with meclofenamic acid (the internal standard), acidified with 5N HC1, and extracted twice with chloroform / dichloromethane / hexane (50 25 25, v/v). The organic phase was evaporated, the residue methylated with ethereal diazomethane, dried again, and reconstituted in hexane. Analytical separation was performed on a 15 m x 0.24 mm i.d., 0.25 pm film thickness, fused silica capillary column. The oven temperature was variable (150 to 260°C) and the injector was at 260°C. The carrier gas was helium at 1 mL/min. Mass spectra were obtained using positive electron impact ionization (70 eV) at m/z 228 for etodolac. The method was linear in the 1-10 ng/mL (low) and 10-100 ng/mL (high) concentration range. The detection limit was 0.5 ng/mL in plasma, and recovery of etodolac from plasma sample exceeded 92%. 

Wang, C.L., Kobayashi, Y., Togashi, H., Kato, K., Hirotsu, T., Hirata, K., Suzuki, R., Ohdaira, T., Mikado, T. (1999) Plasma-polymerized hexam-thyldisiloxane films characterized by variable-energy positron lifetime spectroscopy . J. Appl. Poly. Sci. 74(10), 2522. 

Chance B 1991 Optical method Annu. Rev. Biophys. Biophys. Chem. 20 1-28 Granstrom M, Berggren M and Ingan s O 1995 Micrometer- and nanometer-sized polymeric light-emitting diodes Science 267 1479-81 Hanken D G and Com R M 1995 Variable index of refraction ultrathin films formed from self-assembled zirconium phosphonate multilayers Characterization by surface plasma resonance measurements and polarization/modulation FT-IR spectroscopy Anal. Chem. 67 3761-74... 

Superconducting BSCCO films were produced in situ on 3" diameter sapphire substrates by plasma-enhanced halide LPCVD [266, 267]. Films consisting mainly of the Bi-2212 phase were deposited with metal halide precursors at 580°C under 0.1 Torr system pressure in the presence of a rf plasma. These films became superconducting at 70 K with = 2.5 x 10 Acm at 10 K. Plasma-enhanced halide LPCVD was also used to grow Bi-Sr-Ca-Cu-O/Bi-Sr-Cu-O superconductor-normal metal (S-N) heterostructures [259], HRTEM images showed the S/N interface to be atomically abrupt while variable temperature resistivity measurements gave T. = 75 K for the S/N heterostructure. 

Carbon film prepared from maleic anhydride at —600°C shows a typical room temperature resistivity of —10 ohm-cm and a negative temperature coefficient. Neither a thermal activated process nor variable range hopping is observed in the sample, rather a weak temperature dependence of conductivity at low temperatures. The conductivity of these samples shows a behavior from 300 to 20 K (Fig. 19i) and a T behavior (Fig. 19ii) at still lower temperatures. The following features are found in this plasma-deposited carbon ... 

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