A B S T R A C T
This research, study the effect of the thickness on titanium dioxide
(TiO2) , that prepared by the Sol-Gel Process method on the optical
properties of (TiO2) thin film with different thickness (54, 64 and 89
nm), the thickness effect on optical properties (energy gap , absorbance
spectrum, transmittance spectrum, reflectance, refractive index,
extinction coefficient, absorption coefficient, real and imaginary
dielectric constant) ,this study shows that thickness have an effect on all
these parameters
INTRODUCTION
In the recent years TiO2 films are widely
studied because of their perfect
photocatalytic properties. TiO2 thin films find a
broad range of applications in various fields like
photocatalysis , antireflective ,gas sensing , also
antibacterial, protective coatings and optical
coatings, dielectric films for a new generation
field effect transistors, etc.[1]. Titanium dioxide
is a solid substance,white inorganic , which is
non-stable, poorly soluble, non-flammable ,
cheap non-toxic material that has good
semiconducting properties. Its not sensitivity to
the visible light, because of its band gap , which
have value (3.2) eV [2].Some techniques
including spray pyrolysis, sol–gel coating,
chemical vapor deposition , also rf magnetron
sputtering have been advanced for TiO2 thin
films manufactures . TiO2 films prepared from
these mechanism exhibit a broad variety of
optical properties and structures [3].From across
existing techniques, sol-gel. technique , has
appear as one of the most favorable technique ,
as this method, yields samples with a perfect
homogeneity at low cost. Furthermore, the
processing of sol gel is essentially efficient to
producing transparent, thin ,multi-component
oxide layers of various compositions on many
substrates, counting glass[4].