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All the compounds predicted from the SiNi phase diagram were observed by depositing thin layers of nickel onto silicon in known quantities and ratios to each other using an unreactive substrate such as SiO2. After deposition, the samples were annealed in the temperature range 200–750°C and analysed using 2 MeV 4He+ Rutherford backscattering spectrometry and X-ray diffraction techniques. Ni2Si is the first phase formed at a low temperature (about 250°C). Under silicon-rich conditions the system develops in a reproducible manner, subsequently giving rise, when all the nickel has reacted, to the formation of NiSi and of NiSi2 by reaction at 750°C of the NiSi with silicon. The kinetic diffusion approach accounts for the formation and sequence of Ni2Si and NiSi. The phase Ni5Si2 forms between Ni2Si and nickel under nickel-rich conditions. The phases Ni3Si2 and Ni3Si were observed at 400°C and 450°C respectively.

The phase formation in planar binary systems is discussed in terms of the diffusion-kinetic approach. Application to Pt and Ni silicide thin and thick films confirms this approach and permits to interpret experimental data in terms of the physical mechanisms involved. A temperature-dependent critical thicknessW c for the transition of a compound to its subsequent one is discussed and expressed in terms of the activation energies for the growth and reaction rate.

All the compounds predicted by SiPt phase diagram have been observed by depositing thin layers of Pt on Si in known quantities and ratios to each other by using an unreactive substrate. Emphasis is given to Pt6Si5 and Pt12Si5 formation. They are two new binary compounds which we have experimentally identified for the first time in planar thin film reaction. 4 He + backscattering and X-ray diffraction techniques have been used to analyse the formation of the compounds obtained by thin film deposition and annealing in 200–750°C temperature range. The phases appearance with increasing temperature exhibits a pattern which sequence is presented taking into account the formation temperature and the heat of reaction.

Fast electronic circuits are presented which display, simultaneously and in real time, the most important parameters of a laser pulse. The photodiode detector signal is sent to a compact low-cost system consisting of circuits which measure digitally the pulse width Delta t, frequency f and peak power P'. The pulse width Delta t can be read from two different circuits, one digital and the other analogue. The system is useful for parameter measurements on a pulsed laser beam during irradiation of such materials as biological tissues, where it is very important to control continuously the irradiation dose.