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The NdxFe1-x amorphous thin films with x=0.06-0.80 were prepared at 77 K by flash evaporation. The results show that the amorphous films are stable at room temperature when 0.192 and T untill the crystallization occurs. The crystallization of the amorphous films can not be completed at a certain fixed temperature but over a temperature range.

Simultaneous grain boundary-, surface- and lattice diffusion in hypothetical thin film couples of miscible components was computer simulated. On this basis the diffusion into fixed and moving grain boundaries is discussed with respect to the determination of diffusivities by depth profiling methods. The data evaluated from the synthesised depth profiles according to Whipple-Le Claire as well as to Gilmer and Farrell were compared with the diffusivities used for the computation. Agreement was found for systems with a fixed grain boundary network. Moving grain boundaries, however, may cause errors of an order of magnitude towards lower grain boundary diffusivities

In thin film couples consisting of a 200 A Allayer upon un Ag film of 400 a, diffusion and phase growth were investigated by means of an X-ray optical depth profiling method, making use of the Kiessig interference pattern. Films annealed at 80, 90, 100 and 110°C were examined in subsequent stages of mixing. Mean diffusion coefficients ranged from 10−15 to 10−14cm2s, associated with an activation energy of 25 kcalmol. The alloying process has been identified as the growth of Ag2Al out of the rapidly saturated grain boundary network in addition to the direct growth parallel to the interface. Alloy formation starts with a temperature dependent delay, typical for Ag2Al precipitation.

Gold and its compounds Au2Al, Au5Al2 show marked differences in their spectral reflectivity in the visible range. These differences, observable with the naked eye, have been used to detect the approach of the phase front of diffusionally grown compounds against the gold surface of a Au-Al thin film couple. From a continuous sequence of such couples evaporated in different thicknesses onto the same substrate, i.e. a step-shaped diffusion couple, of a total atomic ratio 2Au/Al, the growth rate constants were obtained The temperature for the diffusion anneal ranged from 333 to 373 K. Excellent agreement with recent literature data for the rate constants was found only in the thicker part of the couple : D=2.1 exp(-1/kT)cm2/s whereas the thinner part showed slightly higher rates.

An x-ray method for the determination of concentration profiles in thin film diffusion couples is presented. This method is based on the theory of Fourier analysis of x-ray diffraction profiles which is generalized to polycrystalline samples showing nonuniform lattice parameter. A Fourier synthesis of the concentration spectrum is possible when the influences of the particle size and the strain in the sample as well as the instrumental function are eliminated from the measured diffraction profile. This can be done by means of reference profiles obtained from layers of the diffusion components. Absorption of the radiation in the sample is negligible when diffusion couples of symmetrical sandwich structure are used. The method is tested experimentally in the system Au-Cu.

Thin films were prepared by quenching Cu-Ag vapour onto substrates cooled with liquid nitrogen. The films were investigated by means of the four-probe technique and electron energy loss spectroscopy. The resistivity was found to be very sensitive to the deposition rate and the substrate temperature. The resistivity of the films depends markedly on the concentration, exhibiting two discontinuities at the boundaries of the amorphous range (30–70 at.%) and peaking at 50 at.%. Transmission energy loss spectroscopy revealed differences in the spectra of amorphous and crystalline specimens. The conductivity values calculated from the plasmon loss position and linewidth on the basis of the nearly-free-electron model were in general higher than those directly measured. This disagreement is due to the limited validity of the model for strong scatterers such as copper and silver. However, the calculated drops in resistivity during phase transitions were in good agreement with those measured.

Specular x‐ray reflections originating at grazing incidence at the boundary planes of thin laminated structures interfere to give the known Kiessig fringes. The change of this interference pattern during diffusion in thin multilayers is used for the study of phase formation in Au‐Al thin film couples. Layered growth of Au2Al obeying a parabolic growth relation was observed in the temperature range from 50 to 80 °C. The activation energy of the process was found to be 1.05 eV.

Interdiffusion between freshly deposited thin polycrystalline films can occur during an initial recrystallization period when grain boundaries act as moving diffusional short circuits. This type of diffusional mixing is investigated on the basis of computer simulations in thin film couples with identical diffusion properties. It is shown that errors in the grain boundary diffusion coefficients towards lower values arise if the Whipple treatment is applied.

On the basis of hypothetical thin film couples in which a grain-boundary supported diffusion process is simulated, it is shown that the concentration spectrum may contain maxima which would not occur if the process were governed by lattice diffusion only. As such maxima consequently appear in the diffraction pattern, real diffraction profiles of interdiffusion layers must be interpreted carefully, keeping in mind that diffraction peaks need not necessarily be associated with a particular phase. The thin-film diffusion system Au-Cu is chosen as an example to demonstrate experimentally the generation of diffraction maxima which must not be attributed to phase formation.

The diffusion coefficients in concentration modulated amorphous CuAg thin films were measured. Both the mean and the isoconfigurational diffusion coefficients obey an Arrhenius relation with pre-exponential factors 8.7 × 10 −5 and 7.3 × 10 −3 cm 2 /s and activation energies 0.85 and 1.18 eV, respectively. The amorphous structure of the films (examined by resistivity measurements and electron microscopy) was maintained despite an atomic mobility large enough for long range diffusion.

Extremely low load indentation hardness testing is one of the few methods of obtaining quantitative information on the mechanical behavior of surfaces and layers. An instrument for testing is described and its capability demonstrated with selected examples. Some peculiarities associated with the evaluation of hardness data of, e.g., a soft layer on a hard substrate or a hard layer on a soft substrate, are discussed.

Hardness testing using a SEM offers visual observation and measurement according to the hardness definition even for submicroscopic impressions. It can provide information on plasticity, homogeneity, adhesion etc. which cannot be obtained from depth measurements alone. The device described operates inside a SEM and offers a load between 10−2N and 10−5N. The influence of test load, rate of load increase and dwell time on the results was examined on various materials.

Some outstandi,,g features of a new device for hardness measurements in a SEM are presented and its capability in optical applications is demonstrated. It will be shown that both the quantitative hardness deterhuination fmail. imprint size as well as a visual observation of the imprint topology are essential for quality assessment.