Tungsten oxynitride (W-O-N) thin films were deposited onto silicon (100) and quartz substrates using direct current (DC) sputtering. Composition variations in the W-O-N films were obtained by varying the nitrogen gas flow rate from 0 to 20 sccm, while keeping the total gas flow constant at 40 sccm using 20 sccm of argon with the balance comprised of oxygen. The resulting crystallinity, optical properties, and chemical composition of the DC sputtered W-O-N films were evaluated. All the W-O-N films measured were shown to be amorphous using x-ray diffraction. Spectrophotometry results indicate that the optical parameters, namely, the transmission magnitude and band gap (E g ), are highly dependent on the nitrogen content in the reactive gas mixture. Within the W-O-N system, E g was able to be precisely tailored between 2.9 eV and 1.9 eV, corresponding to fully stoichiometric WO 3 and highly nitrided W-O-N, respectively. Rutherford backscattering spectrometry (RBS) coupled with X-ray photoelectron spectroscopy (XPS) measurements indicate that the composition of the films varies from WO 3 to W-O-N composite oxynitride films.

M-shell x-ray production cross sections for thorium and uranium have been determined for protons of energies 0.4–4.0 MeV and helium ions of energies 0.4–6.0 MeV. The M-shell line and total M-shell x-ray production cross sections are compared to the predictions of the first Born approximation and ECUSAR ionization theory using recently recommended atomic parameters. Both theories are in good agreement with the data for protons and He ions above 1 MeV. The data of others for energies above 1 MeV protons on uranium, however, fall significantly under the present measurements. Below 1 MeV, with decreasing energy of these projectiles, the first Born approximation increasingly overestimates our measurements while the ECUSAR theory underestimates them to a similar degree. The same trends are seen versus the data of others.

Titanium (Ti) alloys have been widely used in orthopedics and orthodontic surgeries as implants because of their beneficial chemical, mechanical, and biological properties. Improvement of these properties of a Ti alloy, Ti-6Al-4V Eli, is possible by the use of plasma nitriding treatment on the Ti alloy. The novelty of this study is the evaluation of a DC glow discharge nitrogen plasma treatment method on the surface, mechanical and biological properties of Ti alloy. Specifically, this study measured the chemical states, roughness, hardness, and biocompatibility of plasma nitride treated Ti-6Al-4V Eli as well as determined the effect of plasma treatment on the fracture strength between the Ti alloy and bone clement. This study hypothesized that DC glow discharge nitrogen plasma treatment may alter the surface chemical and mechanical states of the Ti alloy that may influence the fracture strength of implant/cement interfaces under static load. This study found that plasma nitride treatment on Ti alloy does not have effect on the roughness and biocompatibility (P value > 0.5), but significantly effect on the hardness and fracture strength of Ti-bone cement interfaces compared to those values of untreated Ti samples (P value < 0.5). Therefore, the DC glow discharge nitrogen plasma treated Ti alloy can potentially be used for orthopedic applications.

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