Özet:
SnO2 films were deposited at 200, 250, 300 ve 350 ± 5 °C substrate
temperature by ultrasonic spray pyrolysis technique. It was seen from the XRD
patterns that all films have polycrystalline structure. For preferential orientations
of the films, half peak widths and grain sizes were calculated. Whether the surface
of the films are homogenous or not was investigated using SEM photographs and
was found that with the increase of substrate temperature homogenity was
increased. It was determined from EDS microanalyses of the films that Sn and O
elements were present in solid films. Using transmission spectra, reflection and
linear absorbtion coefficients of the films were calculated. The variations of these
parameters depending on the wavelength were investigated. It was determined
that forbidden energy gaps varied between 3.1-3.7 eV. The conductivity of the
films in dark were found between 5.40x10-1
-2.24x10-3
(
FP
-1
. I-V
characteristics were used in order to determine the conductivity mechanisms of
the films and it was found that all films have ohmic structure. Using the variations
of electrical conductivities with temperature, the energies of donors and traps like
donor were calculated between 0.28–2.10 meV ve 0.049–0.082 eV for low and
high temperature regions, respectively.