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Thin-film nanophase is a new solid state of metal film on the silicon substrate. Its structure and its properties are different from those of a thick metal film due to an interaction of valence electrons at film-vacuum and film-substrate interfaces and due to a static quantum-size effect and dispersion force in itself film. The interface interaction is limited by a length of the valence electron screening from the side of vacuum and from the side of substrate and it is most expressed in the film thickness range near 1-2 Ǻ (1-2 ML). For film-substrate interface it can be very strong due to a large overlapping of d electrons of transition metal (like 3d metal) and p-electrons of the silicon substrate. In one's turn, the static quantum-size effect and/or dispersion force can stabilize or vice versa destabilize the film in dependence on ratio between the thickness, d, and the De-Broil length of valence electron wave, λF , and/or value of Hamaker constant, respectively. Here we report our experimental results on the conductivity, the morphology, the composition and the electronic structure of pure 3d transition metal films during their near room temperature (20-100 0C) growth on silicon substrate at the thickness range 0-12 Ǻ. Conductivity value versus the thickness showed typical quantum-size character of the dependence behavior. AFM images versus the thickness showed the surface relief stability in the thickness range 0-4.5 Ǻ and the change of the relief after 4.5 Ǻ with formation some ripples in the range of the thickness of 6-12 Ǻ after annealing at 2500 C. AES spectra demonstrated a layer by layer growth mode in all the thickness range with segregation a small quantity of silicon at 12 Ǻ. After annealing AES spectra demonstrated a fixed value and an increased value of the silicon-metal Auger-peak ratio in the range of d = 0-3 Ǻ and 3-12 Ǻ, respectively, with increasing the temperature from 1000 C up to 2500 C. And EELS spectra indicated a redistribution of valence electrons at the metal-silicon interface for 1-2 Ǻ of transition metal on silicon with formation of a lowered concentration of valence electrons in the film. As a whole, the results support above suppositions about the role of an interface interaction and size effects in stability of thin-film nanophases of 3d metals on silicon substrate. |