الفهرس 
Introduction and Aim of the WorkOnly 14 pages are availabe for public view
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Abstract
Zinc oxide (ZnO), a member of the II-VI group semiconductors
with a direct wide band gap (3.3 eV), a large excitonic binding energy (60
meV) at 300 K and availability of large single crystals, possesses a unique
position among materials owing to its superior and diverse properties such as
piezoelectricity, chemical stability, biocompatibility, optical transparency in
the visible region, high radiation hardness, high voltage current nonlinearity,
etc. Also ZnO has a lower threshold voltage for use as a light-emitting diode
(LED) and in laser emission, and TM-doped ZnO is predicted to display
properties of diluted magnetic semiconductors with ferromagnetic Curie
temperature well above 300 K. Thus, ZnO as a multifunctional materials
could be used in a range of industrial applications such as transparent
electrodes, solar cells, gas sensors, photodiode, transistors, surface acoustic
wave devices and for use in spintronics applications. Its low cost compared
with other materials makes it a good candidate for industrial applications.
Recently, nanostructured ZnO has been obtained by using various physical
and chemical techniques.
TM-doped ZnO or Zn1-xTMxO thin films were deposited onto glass
substrates by the sol–gel method via a spin-coating technique. The dopant
ratio x < 10 %. The used transition metal (TM) is copper (Cu) for the first
system, chromium (Cr) for the second system, and for the third system, TM
is cadmium (Cd). The choice of these systems arises from that they are less
investigated; however, they are expected to have excellent optical, electrical,
and magnetic properties and could be used in many research, environmental.