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A high-temperature Auger electron spectroscopy setup and its in situ application to sessile drop experiments of molten silicon on oxide substrates are presented. The experimental setup allows for measurements of previously inaccessible surface reactions at temperatures up to 1700 K. Auger electron spectra of SiO2, MgO, and liquid Si are presented. Furthermore, the areas of the substrates that have been transiently wetted by the silicon melt are investigated. The results are discussed with respect to questions concerning reactive wetting of oxides by metal melts, which are important for the material science of joining processes.

The surface lanthanum element plays a key role in emission mechanism of Lanthanum-contained cathodes. In order to gain insight into the relation between cathode emission properties and the cathode surface La/O ratio, lanthanum-rich film cathodes were prepared in situ by using a set of equipment, specially designed to cathode research, which connected with an Auger electron spectrometer (AES) and pulse laser deposition system. Electron emission properties and surface compositions (lanthanum and oxygen) of the cathodes are investigated experimentally. Experiment results indicate that film cathodes are lanthanum-rich film cathode, there has remained unchanged on film composition in different depth; the cathode emission properties are determined intensively by the surface atomic La/O ratios, the higher the La/O ratio gets, the better the emission property reaches. The excess active Lanthanum is crucial element to the improvement of emission properties.

By using scanning electron microscope (SEM), x-ray energy distribution spectrometer (EDS) and Auger electron spectrometer (AES) to analyze copper conductor melted marks formed by short circuiting in normal atmosphere and fire atmosphere, environmental state when melted marks formed can be judged from contents of elements in composition on the surface of copper conductor melted marks so as to provide scientific bases for identifying fire cause. This paper discusses an analytical study of characteristic of composition on the surface of copper conductor melted marks by using the above three analytic methods.

Positron annihilation induced Auger electron spectroscopy (PAES) is a newly developed application for surface studies with high elemental selectivity and exceptional surface sensitivity. The instrument is operated by the Technische Universität München and is located at NEPOMUC.

Presented is the morphological evolution of cleaved CdTe(1 1 0) during photodissolution in 0.1 M Na2SO4 solution. The surfaces of the photodissoluted CdTe(1 1 0) were imaged with an atomic force microscope, and the morphological variation was found to depend on the illumination level. The CdTe(1 1 0) surfaces photodissolved under illumination of ∼0.6 mW/cm2 were covered with homogenously distributed pits and protrusions, and such a morphology was observed consistently within the experimental time scale (2 h). During photodissolution under ∼7 mW/cm2 illumination, however, the morphology varied in a cyclic manner: pit–plateau–protrusion. It has also been found that after two photodissolution cycles, the surface did not show any apparent cyclic behavior. The compositional change of the CdTe(1 1 0) surface illuminated at ∼7 mW/cm2, measured with an Auger electron spectrometer, was observed to correlate with the morphological variation, as well. Based on the correlation of the morphology and composition, the period of the photodissolution cycle under ∼7 mW/cm2 was estimated to be 30 min. The morphological cyclic variation of cleaved CdTe(1 1 0) surface during photodissolution is interpreted in terms of local Te enrichment.

The high intensity positron source NEPOMUC at the FRM-II in Munich enables measurement times for positron annihilation-induced Auger electron spectroscopy (PAES) of only 2.4 h/spectrum, in contrast to usual lab beams with measurement times up to several days. The high electron background due to surrounding experiments in the experimental hall of the FRM-II has been eliminated and hence background free experiments have become possible. Due to this, the signal to noise ratio has been enhanced to 4.5:1, compared to 1:3 with EAES. In addition, a long-term measurement has been performed in order to observe the contamination of a polycrystalline copper foil at 150 °C.

A remoderator for the high intensity positron source NEPOMUC was developed and installed at the beam facility. A beam of remoderated positrons could be produced with different energies and a diameter of less than 2 mm was obtained. The efficiency of the remoderation setup was determined to be 5%. Due to the brilliance of the remoderated beam, the measurements at the coincidence Doppler broadening spectrometer (CDBS) and at the positron annihilation induced Auger electron spectrometer (PAES) could be improved. The setup and functionality of the remoderation device is presented as well as the first measurements at the remoderator, CDBS and PAES.

オージェ電子分光装置を用いてアルミニウム又はマグネシウム基板上に金属薄膜を蒸着した試料に対して,膜側から電子線を照射し光電子を測定する実験を行った.十分薄く薄膜を蒸着した基板に対して,薄膜側から電子線を照射すると基板から特性X線が発生し,そのX線により薄膜原子が励起されて光電子が発生する.その結果Al基板上の種々の金属からの光電子スペクトル(Au4f,Ag3d,Mn2p,Bi4f,Bi4d,Cls,Pb4f,Pb4d,Sn3d)を得ることができた.更に試料中で起こる現象を考察し光電子の強度式を提案した.この式を用いて合金試料に対して光電子ピークで定量分析を行った結果,相対感度係数法での定量値と比較的よく一致した.更にMg基板上のCuとCuOに対しては化学シフトとサテライトピークを検出することができた.又,本法での空間分解能は通常のXPS分光器よりも優れていることが分かった.

The relationship between hydrogen embrittlement and temper embrittlement of 2.25Cr-1Mo steel was investigated by Auger electron spectrometer testing and electrochemical hydrogen charging. The results indicate that atomic hydrogen increases the grain boundary concentration of impurity element P and temper embrittlement. The increscent temper embrittlement degree by hydrogen will rise with further embrittlement and the relationship between increscent temper embrittlement degree and temper embrittlement degree is ΔCp = log[4.9351×(Cp )1.31687 ]. The grain boundary segregation theory was used and results of theory calculation and testing show that the relationship between hydrogen embrittlement and temper embrittlement can be explained by theory of grain boundary segregation. The embrittlement degree of 2.25Cr-1Mo steel which is induced by hydrogen and temper embrittlement is Cp ′ = log[4.9351×(Cp )1.31687 ]+Cp .Copyright © 2010 by ASME

An cadmium dialkyl-dithiophosphyl-dithiophosphate additive was synthesized. A four-ball tester was used to evaluate the tribological performance of the additive in mineral base oil under different loads, compared with commercial additives. The results show that it exhibits excellent antiwear and load-carrying capacities and better than these additives. The surface analytical tools such as Auger Electron Spectrometer (AES), Scanning Electron Microscopy (SEM) with Energy Dispersive X-ray (EDX) were used to investigate the topography, the contents and the depth profile of some typical elements on the rubbing surface of worn scar. Smooth and light topography of worn scar further confirms that the additive showed good antiwear capacities, the results of Auger electron spectrometer and energy dispersive X-ray analysis indicate that tribochemically protective films consists of cadmium compouds, sulfides, sulphates and phosphates were formed on the rubbing surface, which contribute to improving the tribological properties of lubricants. Particularly, the results from depth profile indicate that a large amounts of cadmium are rich in outer layer of surface, which play an important role in improving antiwear properties of oils. Finally, the antiwear mechanism of the additive were proposed.Copyright © 2005 by ASME

With the recent development of ultra-high vacuum high resolution electron microscopes (UHV-HREM), electron microscopes have become valuable tools for surface studies. Techniques such as surface profile image, surface sensitive plane view, and reflection electron microscopy have been developed to take full advantage of the atomic resolution of HREM to study surface structures. However a complete surface study requires information on both the surface structure and surface chemistry. Therefore in order to turn an electron microscope into a real surface analytical tool, the challenge is to develop a microscopecompatible, surface sensitive tool for in-situ surface chemical analysis.

Auger electron spectroscopy has been used to examine the fracture topography of a medium-grained WC-12wt-%Co and a fine-grained WC-6wt-%Co hardmetal. Specimens of both materials were fractured within the high vacuum chamber of an Auger electron spectrometer to eliminate contamination associated with the examination of samples fractured in air. It was found that the Co/W peak intensity ratio obtained from the fracture surface was higher than that from a polished cross-section and that the ratio decreased to an equilibrium value after subsequent Ar ion sputtering. An analysis of the results indicates that the high initial Co/W peak intensity ratio is due to the presence of Co atoms at WC/WC interfaces and that these interfaces constitute over 50% of the fracture surface.

The paper describes the physical basis and the structure of the algorithms included in the software package for automatic spectrum processing developed recently as an option to the Tesla BP 350.1 Automatic Auger electron spectrometer.

We present an apparatus for Auger electron appearance potential spectroscopy measurements derived from a conventional Auger electron spectrometer. This non-dispersive apparatus is shown to be very sensitive with a high spatial resolution. The utility of the technique has been tested by measuring the 2P levels for some 3d transition metals.

An Auger electron spectrometer with a cylindrical mirror analyzer and a special object stage is described, suitable for investigations at object temperature up to 3000 K without loss of resolution. A preliminary investigation has been conducted of oxygen-tungsten adsorption isotherms at surface temperatures from 1800 to 2600 K and oxygen pressures from about 10 −7 to 10 −4 torr. From these measurements a desorption energy of 6.7 eV has been calculated.

An outline of the design, construction and operation of an inexpensive cylindrical mirror electron energy filter type of Auger electron spectrometer will be presented and some of the problems encountered, discussed.

A design study of a high energy resolution Auger electron spectrometer using retarding electron optical lenses is presented. Important design parameters and constructional details of such an instrument are given. The performance of the spectrometer is assessed and the results show that resolving powers of up to 1200 and scan speeds of up to 1000 eV s-1 have been achieved. Finally the Auger spectra of KCl and MgO are given as examples.

An improved Auger electron spectrometer is presented, using concentric hemispheres accessed by retarding electron lenses. Two modes of operation are available. The first is a constant resolving power mode in which the resolving power is variable from 500 to 4000, by selection of working distance and applied potentials. The collection efficiency is 0.2% of 2 pi sr at a resolving power of 500. The second is a constant hemisphere pass energy mode. By consecutive use of the two modes, the spectrometer will scan from 1 eV to 2 keV. The collection efficiency can be increased to 3% at a resolving power of 300 but aberrations degrade the performance. The analyser is mounted on an 8 in Conflat flange. Finally, the Auger spectrum of lithium is presented.

Magnesia-doped alumina was fractured in a high-vacuum Auger electron spectrometer, and the resulting intergranular fracture surface was analyzed for surface composition. Calcium was present on the fracture surface in amounts of ∼2 to 5 at.%. There was no indication of Mg on the fracture surface. The bulk Ca concentration was 5 to 15 ppm, whereas MgO was present at the 1000-ppm level. The presence of excess Ca at the grain boundary can be explained by the fact that its ionic radius is relatively large compared to those of Al and Mg. Sputtering profiles normal to the fracture surface indicate that the segregated Ca is concentrated in a region near tha intergranular fracture surface.

The fracturing device described allows one to conduct an Auger electron spectroscopy analysis of the grain boundaries of materials fractured in ultra-high vacuum. This can accommodate five 5 mm diameter specimens, which may be cooled to below -150 degrees C prior to fracture.

An Auger electron spectrometer for studies of solid surfaces which is considerably more sensitive than currently used instruments has been developed. The greatly improved signal‐to‐noise ratio of the spectrometer made it possible to display the 0–1000 eV Auger spectrum on an oscilloscope at a scanning rate of 20 000 V/sec. Alternatively, the scanning rate may be reduced to that typical of present instruments (∼2 V/sec) and the primary beam current reduced from 5 × 10−5 to 10−8 A.