Our present work is devoted to analyzing the influence of Ni on the optical properties of ZnO thin films deposited
on glass and Si (100) substrates, with the use of ALD for ZnO deposition and DC magnetron sputtering for Ni
interlayer deposition. The compositions as well as the crystalline structure of various multilayer thicknesses of Ni
(10, 30, 50, and 70 nm), that sandwiched between ZnO Films (70 nm), before being optically characterized, were
carried out by the X-ray diffraction (XRD). Based on the XRD results, the crystallite size was increased with the
increase of the Ni interlayer concentration. Additionally, the material densities for both ZnO and Ni show the
expected close-to-bulk values in all formations, where the large cavities between atoms, on the films make the
dislocation density become smaller and the surface roughness values decrease as well, with the increase of Ni
interlayer concentration. Different optical properties were observed for different Ni content. The optical absorption
coefficient (
α), refractive index (n), and extinction coefficient (k) have been deduced from the trans-
mission T(λ) and absorption measurements A(λ). The optical energy gap E
opt
g
are estimated from Tauc΄s
extrapolation procedure and the Kubelka-Munk approach. The static refractive index (n
), the oscillator energy
(E
o
), and the dispersion energy (E
d
o
) are calculated using the Wemple-DiDomenico (WDD) theoretical model.
Analysis of third-order nonlinear optical properties in crystalline ZnO/Ni/ZnO are being detailed. These promising
results
imply
that
the
high-quality
films
produced
by
ALD,
show
how
the
insertion
of
Ni
could
enhance
the
quality
of
the
optical
properties
of
ZnO
films.
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