The diffusive layering during film growth in two-component systems with limited mutual solubility

The range of deposition temperatures for Ag-Cu system, in which the oriente d phase layering takes place, has been experimentally determined. The mecha nism of this process has been analyzed. During the simultaneous deposition the well-oriented film structures with practically parallel mutual orientat ion of crystal lattices of Cu and Ag phases of high dispersity, alternating across the film thickness, have been obtained. At room temperature the two-phase nanocrystal heterosystem with lateral gra in size of 10-20 nm has been formed. The closeness in the parameters of cry stal lattices is mainly caused by the decrease of a(Ag) down to the values of 0.402-0.405 nm in the substrate temperature range up to 570 K, which cor responds to the solubility of Cu in Ag nanocrystals as much as 17%. When th e substrate temperature increases in a relatively narrow temperature range near 520 K, the oriented crystallization with parallel conjugation of the s ubstrate and the lattices of Ag: and Cu takes place with the grain structur e dispersity preserved. The well defined double diffraction on the grains o f both nanocrystal phases and the homogeneous concentration of components f or the whole film thickness support the relative position of the phases as the alternating lamellae. Thus, during the film growth the layering of the phases was found to occur preferably in the growth direction. The compositi on automodulation in the growth direction leads to the formation of irregul ar layered compositions consisting of very fine mutually oriented lamellae of both phases as large as several nanometers in diameter.