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Titanium aluminum nitride films (Ti 1Ϫx Al x N) have been deposited by reactive magnetron cosputtering. Elemental compositions of these films have been determined by core level photoelectron spectroscopy. Scanning electron microscopy reveals a columnar film growth. This is also reflected by the topography of film surfaces as studied by atomic force microscopy. By x-ray diffraction a crystalline atomic structure is revealed. Single phase samples can be obtained, consisting of the substitutional solid solution ͑Ti, Al͒N. Crystallites show preferential orientation. The optical properties of these films have been investigated by spectrophotometry in the UV-VIS-NIR wavelength range. Depending on the elemental composition, the optical constants vary from metallic to dielectric behavior. For film compositions with xϽ0.5 typical features are a tunable transmission maximum and reflection minimum in the visible spectral range, a high infrared reflection, and a low infrared absorption. Due to these optical properties, Ti 1Ϫx Al x N films are promising candidates for applications such as coatings for solar control windows and optical selective solar absorbers.

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Amorphous hydrogenated carbon films (a‐C : H) containing different amounts of Ti or V were produced by combined plasma‐activated chemical vapour deposition and d.c. magnetron sputtering. New bioactive materials resulted from the combination of the excellent tribological and biological properties of the a‐C : H matrix with the biological response to the incorporated metals. By adding Ti to the a‐C : H matrix, an enhanced differentiation of osteoblast‐ and reduced osteoclast‐like cell activity was achieved, leading to a coating that is valuable for bone implants: enhancing bone ingrowth through increased osteoblast activity and reducing bone resorption through osteoclast‐like cell inhibition. The a‐C : H/V films reduced lysosomal activity as well as neutral red uptake in bone marrow cell cultures, thus being an interesting coating for short‐term implants where reduced cell attachment is required. Prior to cell culture tests, the surfaces of the metal‐containing a‐C : H films were investigated by x‐ray photoelectron spectroscopy. The relation between chemical surface composition and cellular response is discussed. Copyright © 1999 John Wiley & Sons, Ltd.

Natural type IIb diamond surfaces of (IOO), (110), and (111) orientation, as well as chemical vapor deposited (CVD) diamond thin films with (IOO), (110), or mixed orientation are probed by photoelectron spectroscopy in the ultraviolet (UPS) and X-ray (XPS) energy regimes. Dramatic changes can be observed in the valence band and core level spectra of these surfaces upon annealing, hydrogen-plasma exposure, or pulsed dye laser irradiation. The observed changes can be reversed by the exposure of the surfaces to atomic hydrogen (deuterium). The valence band spectra reveal specific surface reconstructions for all three surface preparation methods and moreover a cleaning effect is observed following laser irradiation of CVD diamond surfaces. A comparison to a multitude of theoretical and experimental studies on diamond surface reconstruction is made to elucidate the connection between electronic properties and atomic surface structures. I )

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