This work explores the influence of Fe interlayer thickness on the morphology,
optical, and dielectric behavior of ZnO-based multilayer film prepared by a
combined ALD-DC technique. Morphology was analyzed using focused ion
beam (FIB) and energy-dispersive X-ray spectroscopy (EDX), while optical
properties were evaluated through transmittance and reflectance measurements.
The prepared lamellae confirmed well-defined thickness of each individual
layer, and (EDX) confirmed the absence of other elements present in the thinfilm
samples under study. According to the results presented in the obtained
figures, the increase of the Fe thickness in ZnO/Fe/ZnO system leads to a decrease
in transmittance and an increase in reflectance, refractive index (n), extinction
coefficient (k), and reflectivity (Rref). Both the real and imaginary parts of the
dielectric constant (ε1 & ε2), as well as the dielectric loss (tanδ) increases with
Fe content, while the optical quality factor (Q) decreases. Moreover, the carrier
concentration to effective mass ratio (N/m*) and both optical and electrical
conductivity (σopt & σelec) increases, whereas the electrical modulus (M*) decreases
with increasing Fe thickness. The Wemple-DiDomenico single-oscillator (WDD)
model was employed to determine the dispersion parameters, from which the
nonlinear refractive index (n2) and third-order nonlinear susceptibility (Χ(3)) was
estimated. These results highlight the significant role of Fe in tailoring the optical
and dielectric properties of ZnO-based ͌͂ opto-electronics applications.