We report residual resistivity ratio (RRR) values (up to RRR-541) measured in thin film Nb grown on MgO crystal substrates, using a vacuum arc discharge, whose 60–160 eV Nb ions drive heteroepitaxial crystal growth. The RRR depends strongly upon substrate annealing and deposition temperatures. X-ray diffraction spectra and pole figures reveal that, as the crystal structure of the Nb film becomes more ordered, RRR increases, consistent with fewer defects or impurities in the lattice and hence longer electron mean free path. A transition from Nb(110) to purely Nb(100) crystal orientation on the MgO(100) lattice occurs at higher temperature.

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This paper describes energetic condensation growth of Nb films using a cathodic arc plasma, whose 60-120 eV ions penetrate a few monolayers into the substrate and enable sufficient surface mobility to ensure that the lowest energy state (crystalline structure with minimal defects) is accessible to the film. Heteroepitaxial films of Nb were grown on a-plane sapphire and MgO crystals with good superconducting properties and crystal size (10 mm  20 mm) limited only by substrate size. The substrates were heated to temperatures of up to 700 C and coated at 125 C, 300 C, 500 C, and 700 C. Film thickness was varied from $0:25 m to >3 m. Residual resistivity ratio (hRRRi) values (up to a record hRRRi ¼ 587 on MgO and hRRRi ¼ 328 on a-sapphire) depend strongly on substrate annealing and deposition temperatures. X-ray diffraction spectra and pole figures reveal that RRR increases as the crystal structure of the Nb film becomes more ordered, consistent with fewer defects and, hence, longer electron mean-free path. A transition from Nb(110) to Nb(100) orientation on the MgO(100) lattice occurs at higher temperatures. This transition is discussed in light of substrate heating and energetic condensation physics. Electron backscattered diffraction and scanning electron microscope images complement the XRD data.

Forces associated with globalization have facilitated the development of transnational corporations (TNCs). Such companies have a geocentric orientation and attempt to be responsive to both national markets, while simultaneously seeking global coordination. In this paper we propose that such companies need to reconsider the traditional balance sheet approach to expatriate compensation. Accordingly, we suggest that transnational corporations need to engage in a paradigm shift from the notion of expatriate compensation to transpatriate compensation. We suggest that such a paradigm shift is necessary in light of increasing globalization of markets and operations.

Plasma-based surface modification of niobium is a promising alternative to wet etching of superconducting radio frequency (SRF) cavities. We have demonstrated surface layer removal in an asymmetric nonplanar geometry, using a simple cylindrical cavity. The etching rate is highly correlated with the shape of the inner electrode, radio-frequency (rf) circuit elements, gas pressure, rf power, chlorine concentration in the Cl 2 =Ar gas mixtures, residence time of reactive species, and temperature of the cavity. Using variable radius cylindrical electrodes, large-surface ring-shaped samples, and dc bias in the external circuit, we have measured substantial average etching rates and outlined the possibility of optimizing plasma properties with respect to maximum surface processing effect.