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For a better understanding of the physical and electronic properties of emissive carbon films, one of the best ways is to compare the results obtained with several surface and structural analysis techniques. In this article, different types of carbon film depositions for developing large flat panel displays by field emission displays are analysed and the results are correlated with their emissivity. Pulse laser ablation films, hightemperature plasma-enhanced chemical vapour deposition (PECVD) films and low-temperature PECVD films are characterized by XPS, Raman spectroscopy, X-ray diffraction (XRD), specular X-ray reflectivity, transmission electron microscopy (TEM) and elastic recoil detection analysis (ERDA). The analyses lead us to conclude that the sp 2 /sp 3 ratio is not a crucial parameter for carbon film emissivity. Crystalline structure seems more important. The presence of graphite grains is essential for good and uniform emission. Combination of XPS, TEM, XRD, Raman spectroscopy and ERDA is necessary for the study of carbon film emission.

The quality of the interface between a HfO2 high-k gate dielectric and the Si substrate directly influences its electrical properties. The chemical composition of the interfacial region of HfO2 deposited on a SiO2∕Si(100) substrate by pulsed liquid injection metal organic chemical vapor deposition at 430 and 550°C was investigated by medium energy ion scattering, angular resolved x-ray photoemission spectroscopy analysis, and high resolution transmission electron microscopy. It is shown that the HfO2∕SiO2 interface is abrupt with low roughness and no silicate. The interface roughness with SiO2 is found to be close to that generally measured in silicon technology (silicon oxide above silicon substrates) [E. A. Irene, Solid-State Electron., 45, 1207 (2001)]. The analysis of the experimental results indicates that the deposition technique does not lead to the formation of an extended silicate layer at the HfO2∕SiO2 interface.

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Magnesium fluoride thin films were deposited on silica glass and single crystal silicon substrates by argon ion-beam assisted deposition (IBAD). The effects of argon ions impinging on the growing film on the optical and chemical properties of the single layers were investigated. Compared to MgF2 films produced by direct electron-beam evaporation, the films obtained by IBAD exhibited increased optical absorption and refractive indices, fluorine depletion and increased oxygen contamination. Optical data were analyzed and are discussed with regard to the chemical composition of the films.

Multilayers alternating cobalt with different spacers such as iron and chromium at nanometric scale have been deposited by rf diode sputtering. The structures have been characterized in situ by kinetic ellipsometry and ex situ by grazing x-ray reflection, x-ray diffraction, Auger profile analysis, and transmission electron microscopy. Nuclear magnetic resonance (NMR) and high-field SQUID magnetometry have been used to determine the magnetic properties. In Co/Fe multilayers the structure strongly depends on the cobalt thickness tCo. For tCo below 2 nm, the cobalt layers exhibit a bcc crystalline structure, and the crystalline coherence extends over many periods. For tCo above 2 nm, for Co a mixed fcc-hcp phase has been observed. In this case the crystalline coherence is destroyed from one iron layer to the other. The NMR frequency (198 MHz), and the magnetic moment (1.58 μB/atom) of bcc cobalt have been evaluated. A similar behavior is observed in Co/Cr multilayers, the bcc phase disappearing around tCo=1.5 nm. Moreover, interdiffusion is observed at the Cr-on-Co interface: The samples have zero magnetization up to tCo=0.7 nm. Preliminary experiments show some antiferromagnetic coupling between Co layers. <lz>