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The influence of ion bombardment during microwave plasma chemical vapor deposition (CVD) on diamond film orientation has been investigated. Two interesting findings were obtained: (1) The [001] axes of the grown diamond grains are always along the ion flow direction, perpendicular to the substrate and independent of the crystal orientation of the substrates and (2) for the crystallites which are homoepitaxially grown on the (001) diamond faces parallel to the substrate slight misorientations were found. These new findings confirm the role of ion impact in diamond CVD and can help us to understand the basic mechanism responsible for the crystal orientation in heteroepitaxial diamond films prepared using bias-enhanced nucleation.

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Monolayers of alkyl bisphosphonic acids (bisPAs) of various carbon chain lengths (C4, C8, C10, C12) were grown on aluminum oxide (AlO(x)) surfaces from solution. The structural and electrical properties of these self-assembled monolayers (SAMs) were compared with those of alkyl monophosphonic acids (monoPAs). Through contact angle (CA) and Kelvin-probe (KP) measurements, ellipsometry, and infrared (IR) and x-ray photoelectron (XPS) spectroscopies, it was found that bisPAs form monolayers that are relatively disordered compared to their monoPA analogs. Current-voltage (J-V) measurements made with a hanging Hg drop top contact show tunneling to be the prevailing transport mechanism. However, while the monoPAs have an observed decay constant within the typical range for dense monolayers, β(mono)  =  0.85  ±  0.03 per carbon atom, a surprisingly high value, β(bis) =  1.40  ±  0.05 per carbon atom, was measured for the bisPAs. We attribute this to a strong contribution of 'through-space' tunneling, which derives from conformational disorder in the monolayer due to strong interactions of the distal phosphonic acid groups; they likely form a hydrogen-bonding network that largely determines the molecular layer structure. Since bisPA SAMs attenuate tunnel currents more effectively than do the corresponding monoPA SAMs, they may find future application as gate dielectric modification in organic thin film devices.

A novel low temperature process for titanium nitride (TiN) deposition by means of an electron cyclotron resonance (ECR) plasma CVD process was applied to poly(tetrafluoroethylene) (PTFE). The organometallic compound tetrakis(dimethylamido)titanium (TDMAT) introduced into the downstream region of a nitrogen ECR plasma was used as a precursor for TiN deposition at 100°C.The thin TiN films (thickness 15-30 nm) act as interlayers to activate the electroless deposition of copper followed by an electroplating process. Prior to the deposition of the interlayer, the samples were treated on a biased susceptor with argon ions to enhance the adhesion of the TiN interlayer. This metallization procedure avoids the use of toxic and pollutive etching agents and yields adherent copper layers on PTFE.The maximum adhesion of the metal film on PTFE was established to be 13 N/mm2. As shown by atomic force microscopy (AFM), TiN grains were formed on the fluoropolymer surface. Film composition was investigated by secondary ionization mass spectrometry (SIMS).