The formation of the atomically ordered L1₀-FePd structure during the solid-state reaction in Fe/Pd bilayer thin films is in situ investigated by electron microscopy and electron diffraction analysis. The initial iron and palladium layers were mainly coherently oriented crystallites with the orientation relationship α-Fe (001)[110] || Pd(001)[100]. It is established that the solid-state reaction between the iron and palladium layers upon heating at a rate of 4–8°C/min starts with the formation of the FePd solid solution at 390°C; at 430°C, the formation of the atomically ordered L1₀-FePd structure is observed. It is shown that at the low heating rate (4–8°C/min), the L1₀-FePd structure with the [001] orientation relative to the film plane forms, while at the high heating rate (50°C/min) it forms with the [100], [010], and [001] orientations.

The kinetics of the solid-state reaction between nanolayers of polycrystalline copper and amorphous silicon (a-Si) has been studied in a Cu/a-Si thin-film system by the methods of electron diffraction and simultaneous thermal analysis (STA), including the methods of differential scanning calorimetry (DSC) and thermogravimetry (TG). It has been established that, in the solid-state reaction, two phases are formed in a sequence: Cu + Si → η″-Cu₃Si → γ-Cu₅Si. It has been shown that the estimated values of the kinetic parameters of the formation processes for the phases η″-Cu₃Si and γ-Cu₅Si, obtained using electron diffraction, are in good agreement with those obtained by DSC. The formation enthalpy of the phases η″-Cu₃Si and γ-Cu₅Si has been estimated to be: ΔH_η″-Cu3Si = −12.4 ± 0.2 kJ/mol; ΔH_γ-Cu5Si = −8.4 ± 0.4 kJ/mol. As a result of the model description of the thermo-analytical data, it has been found that the process of solid-state transformations in the Cu/a-Si thin-film system under study is best described by a four-stage kinetic model R3 → R3 → (Cn-X) → (Cn-X). The kinetic parameters of formation of the η″-Cu₃Si phase are the following: E_a = 199.9 kJ/mol, log(A, s⁻¹) = 20.5, n = 1.7; and for the γ-Cu₅Si phase: E_a = 149.7 kJ/mol, log(A, s⁻¹) = 10.4, n = 1.3, with the kinetic parameters of formation of the γ-Cu₅Si phase being determined for the first time.

The effect of the aluminum layer on the kinetics and mechanism of aluminum-induced crystallization (AIC) of amorphous silicon (a-Si) in (Al/a-Si)_n multilayered films was studied using a complex of in situ methods (simultaneous thermal analysis, transmission electron microscopy, electron diffraction, and four-point probe resistance measurement) and ex situ methods (X-ray diffraction and optical microscopy). An increase in the thickness of the aluminum layer from 10 to 80 nm was found to result in a decrease in the value of the apparent activation energy E_a of silicon crystallization from 137 to 117 kJ/mol (as estimated by the Kissinger method) as well as an increase in the crystallization heat from 12.3 to 16.0 kJ/(mol Si). The detailed kinetic analysis showed that the change in the thickness of an individual Al layer could lead to a qualitative change in the mechanism of aluminum-induced silicon crystallization: with the thickness of Al ≤ 20 nm. The process followed two parallel routes described by the n-th order reaction equation with autocatalysis (Cn-X) and the Avrami–Erofeev equation (An): with an increase in the thickness of Al ≥ 40 nm, the process occurred in two consecutive steps. The first one can be described by the n-th order reaction equation with autocatalysis (Cn-X), and the second one can be described by the n-th order reaction equation (Fn). The change in the mechanism of amorphous silicon crystallization was assumed to be due to the influence of the degree of Al defects at the initial state on the kinetics of the crystallization process.

Owing to the fact that ultrathin platinum films have many practical applications, the information concerning the initial stage of the formation of these films raises considerable interest. The effect of the film thickness on the morphology, as well as on the electrical and optical properties, was experimentally studied by a combination of methods (TEM, SAED, SEM, AFM, optical spectrophotometry, and electrical resistance measurements). The growth mechanisms of the films with an average thickness from 0.2 to 20 nm were determined, which is equivalent to the thickness of 1 to 100 monolayers (ML). The percolation threshold was reached, with the average film thickness being ≈1.0 nm, when electrical conductivity appeared. With an average thickness of ≈2.0 nm, the platinum films became almost continuous. The obtained data were analyzed within the framework of scaling theory. The growth of the platinum films at the initial stage (0.2–2.0 nm) was shown to proceed in the mixed 2D/3D growth mode. Here, 3D nanoislands, having a crystalline structure, were formed simultaneously with the formation of an almost continuous 2D subnanometer layer possessing an amorphous-like structure.