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Thin titanium hydride (TiHy) films are compared with thin titanium films after analysis using a combination of scanning electron microscopy (SEM), Auger electron spectroscopy (AES) and angle‐resolved x‐ray photoelectron spectroscopy (ARXPS). The TiHy films were prepared under ultrahigh vacuum conditions by precisely controlled hydrogen sorption at 298 K on Ti films evaporated onto a glass substrate. Analysis was performed in separate systems after long‐term exposure of the films to air. Scanning electron microscopy analysis revealed a grain structure of the TiHy film, with a smaller grain size than the Ti film. Both the surface and bulk regions have been analysed in terms of their chemical composition and elemental distribution. Titanium dioxide was found to be the main chemical compound forming a contamination layer on both the TiHy and Ti film surfaces. Also, significant concentrations of carbon monoxide and hydrocarbon as well as small amounts of nitrogen and titanium carbide were detected. The thickness of the contaminated titanium oxide layer on the TiHy and Ti films was found to be ∽13 and ∽20 nm, respectively. Long‐term air interaction with the TiHy film leads to bulk penetration of oxygen but not to complete TiHy decomposition. © 1998 John Wiley & Sons, Ltd.

A combination of SEM, AES and angle-resolved XPS (ARXPS) has been applied to analyse the distribution of chemical compounds in the surface region of electrochemically etched molybdenum tips and to determine the contamination layer thickness. Carbon monoxide, graphite, molybdenum carbide and molybdenum oxide were found to be the main surface contaminants on molybdenum tips. Auger line profiling revealed a significant enrichment of carbon and oxygen upon the tip. The thickness of the oxygebcarbon contamination layer on the tip was estimated to be 135 & 1.0 nm as measured by AES. The thickness of the contamination layer on a molybdenum sheet was found to be 8.0 f 15 and 6.8 am using AES and ARXPS respectively. Quantitative analysis of the surface concentrations of carbon, oxygen and molybdenum has been performed.

Thin titanium deuteride (TiD(y)) films, covered by an ultra-thin palladium layer, have been compared with the corresponding titanium and palladium films using a combination of scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The TiD(y) layers were prepared under ultra-high vacuum (UHV) conditions by precisely controlled deuterium sorption at 298 K on a Ti film evaporated onto a Si(100) substrate. Both Ti and TiD(y) films were then covered in situ by a nanoscale Pd layer. It was found that a 10- to 12-nm-thick Pd layer protects the TiD(y) films efficiently against extensive air interaction. The morphology of both the surface and bulk Pd/TiD(y) (Ti) films have been observed using SEM and cross-sectional TEM analysis, respectively. A polycrystalline bulk morphology in both Ti and TiD(y) films accompanied by a fine-grained Pd surface was observed. High-magnification cross-sectional TEM images reveal the TiD(y) film to be plastically deformed leading to an increase in the roughness of the top Pd layer. Complex structures, including Moiré patterns, have been identified within the Pd/TiD(y) interface. The chemical nature of this interface has been analysed after partial sputtering of the Pd top layer using XPS. Besides TiD(y) and Pd, TiO and PdO were found to be the main chemical species in the interface region of the Pd/TiH(y) film. The XPS valence-band spectra of the Pd/TiD(y) interface reveal electronic features characteristic of a Pd-Ti bimetallic structure.