Influence of the additional interfaces in nanoscale layered Pt/Fe film on the SiO$_{2}$(100 nm)/Si substrate, with the retention of initial film thickness (of 30 nm), on the diffusive phase-formation processes–transformation of soft-magnetic chemically disordered A1(FePt) phase into hard-magnetic chemically ordered L1$_{0}$(FePt) phase at annealing in vacuum is investigated by methods of physical materials science: X-ray diffraction, atomic force microscopy and magnetic force microscopy, Rutherford backscattering, SQUID magnetometry, and electrical resistance measurements. As revealed after deposition, these films have bi- and four-layer structures, respectively. Annealing in vacuum in the temperature range of 600—900°C with annealing time of 30 s is accompanied by phase transformation. Introduction of additional interfaces improves the ordering kinetics. These facts are illustrated with decrease of formation onset temperature for the ordered L1$_{0}$(FePt) phase with (111) texture in [Pt(7.5 nm)/Fe(7.5 nm)]$_{2}$ multi-layered films by 100°C as compared with Pt(15 nm)/Fe(15 nm) films, in which the A1(FePt) → L1$_{0}$(FePt) phase transformation occurs during annealing at 700°C. Coercive force of films increases with increasing the annealing temperature.