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A thin layer of iron coating and subsequent post-annealing (Fe-coating/post-annealing) is seen to significantly enhance the electron field emission (EFE) properties of ultrananocrystalline diamond (UNCD) films. The best EFE properties, with a turn on field (E0) of 1.98 V/μm and current density (Je) of 705 μA/cm2 at 7.5 V/μm, are obtained for the films, which were Fe-coated/post-annealed at 900 °C in H2 atmosphere. The mechanism behind the enhanced EFE properties of Fe coated/post-annealed UNCD films are explained by the microstructural analysis which shows formation of nanographitic phase surrounding the Fe (or Fe3C) nanoparticles. The role of the nanographitic phase in improving the emission sites of Fe coated/post-annealed UNCD films is clearly revealed by the current imaging tunneling spectroscopy (CITS) images. The CITS images clearly show significant increase in emission sites in Fe-coated/post-annealed UNCD films than the as-deposited one. Enhanced emission sites are mostly seen around the boundaries of the Fe (or Fe3C) nanoparticles which were formed due to the Fe-coating/post-annealing processes. Moreover, the Fe-coating/post-annealing processes enhance the EFE properties of UNCD films more than that on the microcrystalline diamond films. The authentic factor, resulting in such a phenomenon, is attributed to the unique granular structure of the UNCD films. The nano-sized and uniformly distributed grains of UNCD films, resulted in markedly smaller and densely populated Fe-clusters, which, in turn, induced more finer and higher populated nano-graphite clusters.

The properties of bulk polycrystalline p‐type Mn:CuInTe2 (with up to 12% Mn substitution) have been examined using polarized light microscopy, x‐ray energy dispersive analysis, optical spectrometry, van der Pauw technique, and superconducting quantum interference device magnetometer measurements. The compound (Cu1−xMnx)InTe2 is a tetragonal chalcopyrite with lattice constants nearly equal to that of CuInTe2. On the other hand, attempted substitution of Mn in In sites produces a second phase composed of Cu and Te. The band gap of Mn:CuInTe2 is larger than 0.92 eV. Most samples show phonon‐limited mobility, with the highest mobilities occurring at ≊75 K. Samples with 3% Mn substitution in Cu sites are paramagnetic. At higher Mn concentration (9%

We have fabricated refractory superconducting NbNxCy thin films on unheated Si substrates with a low‐energy dual ion‐beam sputtering technique. Films fabricated with this technique have predominantly B1 crystal structure with maximum Tc ∼13.2 K, resistivity of 80–150 μΩ cm and residual resistance ratio ∼1.0. The use of low ion‐beam energies and the absence of substrate heating make this method well suited for producing NbNxCy films for superconducting microelectronic applications.