Interdiffusion and chemical ordering in composition-modulated Fe70Si30/Si amorphous thin films

Abstract
The interdiffusivity and chemical ordering in compositionally modulated (Λ=20 to 40 Å) amorphous Fe70Si30/Si thin films have been measured from the decay of the satellite intensities of the (000) x‐ray scattering peak during isothermal anneals in the temperature range 373–473 K. Diffusivities as low as 1026 to 1025 m2 s1 have been measured. A linear dependence of D̃Λ on 1/Λ2 has been observed, providing the evidence of chemical ordering in Fe‐Si alloy and leading to the determination of a critical wavelength.