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It has been possible to optimize direct-current plasma-enhanced chemical vapor deposition with C2H2 and NH3 gas mixtures to synthesize aligned carbon nanotubes on Co- or Ni-covered W wires in respect of gas pressure, wire temperature, sample bias and wire diameter. It was found that the optimum pressure region for aligned carbon nanotube growth grew wider with a rise in wire diameter.

The formation of carbon nanotubes and their filling with metallic fibers developing on field anodes in the anode activation procedure were investigated. These carbon nanotubes were not perfectly graphitized, in contrast to the multishell carbon nanotubes formed in arc plasmas. The metallic fibers grown inside the nanotubes contain chromium as their primary component but their structure did not conform to any of the known compounds of Cr nor to elemental Cr.

Scanning and transmission electron microscopic studies of Ar+ sputter-induced cones on nickel-seeded silicon suggest that Ni atoms are highly deposited on the upper cone slope to form delta-winged cones at temperatures lower than 400 degrees Celsius. At temperatures below 200 degrees Celsius, Ni formed the seed layers, while nickel silicide is observed above 200 degrees Celsius, which is silicidized to NiSi2 above 300 degrees Celsius. NiSi2 formation is triggered by Ar+ bombardment. Around 500 degrees Celsius, an eutectic reaction between Ni and Si is triggered by impacting Ar+ ions.

An x-ray irradiation system of field-emission type has been constructed using carbon-nanofibers (CNFs) grown on a palladium wire that is 50 μm in diameter. The electron current emitted from the CNFs was approximately 1 mA and was stable within 10% for a long time t>5000 h. The electrons passing through a slit in the gate electrode were accelerated to the desired energy, and were made to impinge on the metal target (Ti, Cu, Mo, and W) for generating x rays. The x-rays transmitted through Be-window were characterized using energy analyzers and a dosimeter. At an acceleration voltage of Va=50 kV, the energy spectra of the x-rays were exclusively composed of characteristic signals except for the Mo-target, and the dose rates of x-rays were D=2.5–14 Gy/min, depending on the target metals. This system also provides sharp x-ray images of both biological and nonbiological materials. [ABSTRACT FROM AUTHOR]

Presents information on a study which systematically depth profiled polycrystalline aluminum, molybdenum, and titanium films deposited on silicon wafers by Auger electron spectroscopy using argon and nitrogen ions as projectile. Methodology of the study; Results and discussion; Conclusions.

Examines vertical element redistribution in nickel[sub78]boron[sub11]silicon[sub11] amorphous films deposited on silicon wafers. Details on the experiment; Results of the study; Discussion of findings.

Presents a study which examined the redistribution behavior of metalloid atoms in the amorphous alloy Ni[sub75]B[sub15]Si[sub10] by means of a scanning Auger microprobe. Characteristics of liquid-quenched amorphous alloys or metallic glasses; Advantages of using the scanning Auger microprobe; Observation on the Auger spectrum from an unannealed sample sputter etched briefly.