In this work, the effect of electric permittivity and thin layer thickness on the energy
gape has been studied in a system consisting of three thin layers by means of finding the
self action potential of charge carrier located in the central layer
of this system. Then, the
self action potential energy has been found by solving Schrödinger equation at the
extracted potential. This study shows that energy gape of PbI2 decreases with layer
thickness while it increases/decreases according to comparison between dielectric
permittivity values of central layer and counterparts of two neighborhood layers on both sides.
Mn doped tin oxide transparent conducting thin films were deposited at a
substrate temperature of 450°C by spray pyrolysis method. Structural
properties of the films were investigated as a function of various Mn-doping
levels (0, 1, 3, 5, 7 wt%) w
hile all other deposition parameters such as
substrate temperature, spray rate, carrier gas pressure and distance between
spray nozzle to substrate were kept constant.
In this paper samples of poly vinyl chloride PVC ,pure, irradiated
with Gama rays, were prepared by casting method in room
temperature and light, and under atmosphere pressure.
It was observed from this research that irradiation made real effect
on some of the studied optical properties, the irradiation increased
the transmittance while the electronic transitions kind remained
indirect before and after the irradiation.
In this research we have prepared thin films from poly vinyl chloride (PVC) by spin
coating technique in three velocities (1000,2000,3000)RPM on glass substrate (Micro
scope cover glass), at room temperature. The absorbance A, and transmittance T f
or the
films were studied in the visible and ultra-violet region (UV-VIS). In addition,we have
calculated the absorbance coefficient α, skin depth δ, refractive index no, dielectric
constant ε (the real part and the imaginary part), also we have calculated the energy band
gap of allowed and forbidden direct transitions.
The films showed high transmittance (80-90)%, in the infrared region as a function
of the spinning velocity and took the maximum value 80% for the velocity 1000RPM, and
90% for the velocity 3000RPM, and the refractive index was decreased with the velocity
increase, we found it between3.67 and 4.56 for the velocities 3000RPM and 1000RPM
respectively. Whereas the skin depth δ decreased with the increasing of velocity, the
minimum value was 0.0000531cm for the velocity 3000RPM and the maximum value was
almost 0.00023cm for the velocity 1000RPM.
The work could be considered as a continuous study of (XRL) X – ray luminescence - spectra of pure, and mixed Zno different AL ions, In these films and other crystals powders prepared by new developed te chnology.
We studied the pure and ZnO thin
films. mixed with an AL - ions in the fielol (200-700)nm ,at different weig hrs (5,10,15,20)wt% prepared by thermal evaporation. This way is cheep and a simple technology.
Our study showed different spectra peaks at the wavelengths(335,410,521)nm anol (t=20ns)produced, at different peaks intensities of the prepared thin films, compared with those jure and mixeol ZnO ones, spray pyrolysis.
Thin films technology, have many wide scientific application, in the medical field, Lazer technology, Luminscence counters, and at the solar cells fields
This research is a theoretical study for the scattering mechanism of the charge carrier in the transport tunnels of system consisting of metal-insulator- semiconductor (MIS)- When the insulator is polarized where the conductivity of surface for semic
onductor polarization behavior due to charge transfer during interfaces. The aim of this research is to investigate the effect of self-action and polarization potentials on the ground state of electron- polaron in semiconductor layer by means of is olating the Schrodinger equation and discussion of some special cases such as the potential is triangular form (case of contact metal – semiconductor).
The thin films of TiO2 were prepared by the Sol-Gel, on glass
subtracts by using the following initial solutions: trichlorethylene
titanium, ethanol, sodium hydroxide and hydrochloric acid and
distilled water. The films were annealed at temperatur
es(200- 300-
400-500)c° for 1 hour. The structure of the prepared and annealed
films were studied by XRD. The XRD rusltes showed that the films
prepared crystallize according to orthorhombic Structure.Lattice
constants were calculated and it was found that it was consistent
with the data JPCDS and with some scientific works.
In this paper we present a study of ZnS thin films thermally deposited on
glass substrates, with different optical thicknesses. On topography micrographs
and feature parameters obtained by Atomic Force Microscope, we pursued the
islands formation
and growing in ZnS thin films even on the same optical
thickness of the film. For doing so, we analyzed the micrographs surface, using
Watershed Segmentation and Wolf pruning that allow the detection of
significant features on surfaces, Grain sorting operator and Parameter
Distribution Study.
In this paper we present the preparation of PbS nanocrystalline thin films
using Chemical Bath Deposition (CBD) technique. We have performed this
work in order to study the photoconductivity of PbS semi-conductor thin films.
The details of the pre
paration method are described. Thickness of deposited
films has been determined using mechanical and optical methods. From the
optical absorption measurements we have determined the band gap values.
Using the first approximation parabolic bands model and the obtained values
of band gaps, we have determined the size of PbS nanocrystallites. Also, we
have investigated the electrical and photoelectrical behaviors of the PbS films.
Our study shows that the size of PbS thin films nanocrystallites affects the
photoconductive properties of the material. Furthermore, investigations show
that there are two different sizes of grains located in two different layers, the
first one, with grain’s size of about 25nm, concerns the part of PbS deposited
directly on the glass substrate and the second layer, with grain’s size of about
70nm, concerns the PbS deposited on the first layer.
