الفهرس 
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Abstract
Abstract
I
Abstract
Nanostructured materials have received more interest recently due to
their excellent properties such as a large surface-to-volume ratio, increased
activity and special electronic properties. A large number of studies have
devoted to study metal oxide nanocrystalline powder due to their versatile
application in different areas. Among all metal oxide nanoparticles, Cupric
Oxide (CuO) has gained the most interest because of its wide applications
and narrow band gap of 1.3–2.1 eV.
In this study CuO was successfully synthesized by different chemical
routes. Co-perception and sol-gel methods were used for preparing CuO in
powder and thin film form, respectively. Structural investigation using Xray powder diffractograms confirmed that the powder has a monoclinic form
with lattice constants of a=4.709 Ǻ, b= 3.395 Ǻ and c= 5.037 Ǻ. Also, the CuO
thin films were found to be monoclinic with lattice parameters; a=4.672,
b=3.432 and c=5.123Å. The Fourier transformation spectroscopy, FT-IR,
technique was used to investigate the molecular structure of the synt hesized
Cupric oxide in powder and thin film form. The investigated spectra of the
synthesized CuO confirm the formation of monoclinic CuO phase.
The morphology of the prepared CuO powder was investigated by the
scanning electron microscopy, SEM. SEM images of as-prepared CuO
microstructure shows a spherical-like morphological. The surface
topography of the prepared thin films was studied by using atomic force
microscopy, AFM. Nano-roughness data was calculated over the whole
Abstract
II
image (area) with cited numbers resulting from at least three images of
4040 m
2
and 11 m
2
. Roughness parameters were calculated using ”SPIP
6.2.0” software.
The electrical conductivity and dielectric properties of CuO pellets
have been investigated in the frequency range from 42 Hz to 1MHz and in
the temperature range 293–523 K. The Complex impedance of CuO
nanoparticles was analyzed by the real and imaginary impedance parts at
different temperature and frequency. The Cole-Cole diagram was
investigated by using the real and imaginary parts of the impedance. The
frequency dependence of σ(ω, T) follows the Jonscher’s universal dynamic
law. The correlated barrier hopping (CBH) model has been applied to the
interpretation of the a.c. electrical conductivity. The barrier height was
calculated and found to be ≈1.1eV. The dc conductivity was investigated
from the extrapolation of ac conductivity and calculated from the extracted
CuO bulk resistance. The dc conductivity
dc
of synthesized CuO
nanoparticles was found to be
5 1 1
1.2175 10 m
at room temperature and
the activation energy is found to be
0.34 eV
. Complex dielectric constant
and electric modulus were analyzed by its real and imaginary parts of
dielectric constant and electric modulus, respectively, under the influences of
temperature and frequency.
Photovoltage-characteristics for Ag/CuO/p-Si/Al Schottky diodes
showed a good photoconductive response. Cheung-Cheung and Nord’s
methods were used to investigate and estimate the technical parameters of
Ag/CuO/p-Si/Al diodes. The electronic parameters such as ideality factor, n,
Abstract
III
barrier height, , and series resistance, Rs, were found to be 1.876, 0.93 eV
and 4kΩ, respectively. The interface-state density of Ag/CuO/p-Si/Al diodes
was investigated and found to vary from 2.2x10
15
to 1x10
14
eV
-1
.cm
−2
. The
calculated photocurrent was increased from 94 nA to 9.3 A as the
illumination power was increased from zero to 100 mW/cm
-2
, respectively.
The C–V and G–V characteristics of the diode were also investigated at
different frequencies.