[en] Routine evaluation in X-ray photoelectron spectrometry comprises the standard evaluation steps 1) energy calibration 2) sample charging 3) spectrum processing 4) binding energy 5) layer thickness determination 6) quantitative analytics. This work shows the foundations and describes the development of computer codes for an on-site evaluation of measurement data with the help of an EPSON HX-20 computer. (Author, translated by G.Q.)

[en] With new and advanced analytical imaging methods emerging, the limits of physical analysis capabilities and furthermore of data acquisition quantities are constantly pushed, claiming high demands to the field of scientific data processing and visualisation. Physical analysis methods like Secondary Ion Mass Spectrometry (SIMS) or Auger Electron Spectroscopy (AES) and others are capable of delivering high-resolution multispectral two-dimensional and three-dimensional image data; usually this multispectral data is available in form of n separate image files with each showing one element or other singular aspect of the sample. There is high need for digital image processing methods enabling the analytical scientist, confronted with such amounts of data routinely, to get rapid insight into the composition of the sample examined, to filter the relevant data and to integrate the information of numerous separate multispectral images to get the complete picture. Sophisticated image processing methods like classification and fusion provide possible solution approaches to this challenge. Classification is a treatment by multivariate statistical means in order to extract analytical information. Image fusion on the other hand denotes a process where images obtained from various sensors or at different moments of time are combined together to provide a more complete picture of a scene or object under investigation. Both techniques are important for the task of information extraction and integration and often one technique depends on the other. Therefore overall aim of this thesis is to evaluate the possibilities of both techniques regarding the task of analytical image processing and to find solutions for the integration and condensation of multispectral analytical image data in order to facilitate the interpretation of the enormous amounts of data routinely acquired by modern physical analysis instruments. (author)

[en] The technique of quantitative Auger electron spectroscopy (AES) is central to modern surface analysis. Development, both in terms of new instrumental apparatus and the theoretical basis of Auger analysis, has been the subject of intense research. The work presented here investigates two of the current issues surrounding Auger electron spectroscopy and microscopy. The modelling of electron-solid interaction is reviewed, and investigations are carried out into the two well established computational techniques, transport theory and Monte Carlo simulation. The transport mean free path, λ_tr and the inelastic mean free path, λ_i describe electron transport in solids to the first order. Variations in these parameters with energy and atomic number are explored with a view to identifying trends and establishing the extent to which generalisations are valid. Although transport theory calculations have been shown to give an accurate representation of true electron behaviour, their application is largely limited to homogeneous materials. Monte Carlo modeling provides us with a more rigorous treatment of complex experimental conditions. A new Monte Carlo model is presented which allows extension of existing simulations to incorporate heterogeneous, multilayered samples. The design of integrated circuits is an extremely fast moving technology, with routine manufacture of nanometric feature sizes now becoming a reality. The second part of this work is devoted to the design of an angle resolved electron spectrometer with a very high resolution field emission electron probe. It is intended that high resolution analysis, coupled with the ability to resolve the azimuthal component of electron trajectories, will offer new insight into the surface features of ultra large scale integrated circuits. (author)

No abstract available

[en] L/sub III/ absorption measurements on a number of Ce-based systems together with their La and/or Pr isomorphs, show that the double peaked Ce-edge is not caused by final-state shakeup processes. Shakedown satellites were identified in the absorption edges of LaNi₅ and LaPd₃ by comparing to isomorphs of heavier rare earths. The observed smallness of final-state effects implies that the method of L/sub III/ absorption is both a convenient and reliable method for measuring the mixed-valent quotient. XPS and L/sub III/ absorption measurements were performed in a system where the electronic bandstructure can be varied continuously; namely Ce(Pd/sub 1-x/ T/sub x/)₃ where T = Rh or Ag. The shakedown intensities in the Ce 3d core levels were correlated with the mixed-valent behavior in this system. The two peaks in the 4f-derived photoemission in Ce-based systems have been a major puzzle in the understanding of these mixed valent effects. Several theories have tried to explain this phenomenon. Resonant valence-band photoelectron measurements were performed on the systems REAl₂, RERu₂ and REPd₃ (RE = La, Ce, Pr, and Nd). One observes the biomodal 4f spectrum in PrAl₂, PrPd₃, and NdPd₃, as well as in the Ce-isomorphs

[en] Please find the abstract and the fulltext under the available link.

[en] The problem of interchangeability of surface analytical data is gaining increasing importance in multi-method surface analysis. As the VAMAS project and publications of M.P. Seah and the VAMAS Community show, a standardized data exchange format is necessary to allow an efficient exchange of data and control information obtained by different analytical tools. Computers used to control measurement instruments generally work with proprietary software under various operating systems. Only a standardized data exchange format can guarantee the independence of proprietary measurement systems without adaptation of existing software. Therefore, the software package MAXMIND based on public domain software products was developed. It is used for the transfer, archiving and editing of surface analytical data based on HDF. MAXMIND contains all available and necessary information on experimental conditions and all parameters specific for a number of analytical techniques such as Auger Electron Spectroscopy and Microscopy etc.. Additionally, all data concerning the state of the sample are summarized in the sample history, and the state of the instrument at the time of the measurement is summarized in the instrument description. One or more measurement series can be stored in a binary HDF-file comprising the 'subfiles' sample history, instrument description, description of the measurement series, measurement descriptions for each measurement and data files for all maps and spectra. In this way all data concerning a measurement series are combined in a single file in order to allow a well-founded evaluation of the data and an enhanced reproducibility of the experiment. (author)

[en] Measurements were made of diffusion and thermal relaxation in amorphous Cu₅₀Zr₅₀. Samples were prepared by melt-spinning under vacuum. Diffusion measurements were made over the temperature range from 317 to 385 C, using Ag and Au as substitutional impurities, by means of Auger electron spectrometry (AES) and Rutherford backscattering spectrometry (RBS). Thermal measurements were made by differential scanning calorimetry (DSC) up to 500 C. The diffusion coefficients of Ag and Au in amorphous Cu₅₀Zr₅₀ are found to be somewhat higher than, but very close in magnitude to the coefficient of self-diffusion in crystalline Cu at the same temperatures. The activation energies for diffusion in the amorphous alloy are 0.72 to 1.55 eV/atom, much closer to the activation energy for self-diffusion in liquid Cu, 0.42 eV/atom, than that for the crystalline solid, 2.19 eV/atom. The mechanism for diffusion in the amorphous metal is presumably quite different from the monovacancy mechanism dominant in the crystalline solid. The pre-exponential terms are found to be extremely small, on the order of 10^-10 to 10^-11 cm²/sec for Ag diffusion. This indicates that diffusion in amorphous Cu₅₀Zr₅₀ may involve an extended defect of 10 or more atoms

[en] Sputter-deposited amorphous silicon-carbon films (a-Si_1-xC_x, x=0..1) have an important potential as semiconductor material or as first-wall material in fusion reactors. A particular feature of sputter-deposition is that the mean energy of the deposited atoms is in the range of a few electronvolts. In this thesis some basic properties of such a-Si_1-xC_x films are explored, e.g. the atomic density, the atomic concentration, and the behaviour of the Si- and C-bonds. In the second part the influence of oxygen exposure during growth is investigated. X-ray photoelectron spectroscopy (XPS) is mainly used for analysis. Additional information was obtained form Rutherford backscattering spectroscopy (RBS), nuclear reaction analysis (NRA), Auger electron spectroscopy (AES), X-ray induced AES (XAES), energy dispersive X-ray spectroscopy (EDX), and infrared transmission spectroscopy (IR). (orig.)

[en] The unoccupied electronic states of;Ni(111) and Al(111) have been studied using angle-resolved inverse-photoemission (IPE) spectroscopy. We have characterized the n = 1 image potential state on Ni(111) measuring an effective mass of m^*/m = 1, consistent with recent two-photon photoemission results as well as theoretical calculations using a phase-analysis model, but differing considerably from the earlier angle-resolved IPE measurements. The bulk related features on Ni(111) observed in our experiment agree very well with an empirical Ni band structure calculation. On Al(111), we have conducted an extensive study of the image potential resonance using both angle-resolved IPE spectroscopy and tunneling spectroscopy with the scanning tunneling microscope. We have used Al as a testing case for both nearly-free-electron model and first-principles calculations were needed to obtain a semi-quantitative account of the bulk features of Al, a simple metal. Improved quantitative agreement occurred when excitation effects were considered. In addition, several surface resonance features have been identified and characterized on Al(111). We have also conducted a geometric structural investigation of a metal overlayer system, Ni/Cu(111), using high-resolution electron energy loss spectroscopy with CO as a probe molecule. The results indicate island formation and two-dimensional mixing at the initial stage of bimetallic interface formation. A new adsorption site with CO bonded to both Ni and Cu has been discovered on the Ni-Cu intermixed surface. IPE results for the Cu-covered Ni(111) surface show an enhanced angular range for the Cu image state. Finally, the unique ability of Auger-photoelectron coincidence spectroscopy to probing local valence electronic structure has been tested in a case study of TaC(111). A novel Auger decay channel has also been observed