Authors
Abstract
:Cu0.5Ag0.5AlS2 thin film had been doped by (Cd) and (Pb) elements, with amount of (1,
2, 3, 4, 5)wt% and studied the effect of doping by Cd and Pb on the optical properties for this thin film
which prepared by chemical spray pyrolysis at 360Co .When the thin film was doped by Cd ,from the
absorption and transmission spectrum of the prepared thin films in the range (300 – 1000) nm, the
optical constants were calculated. The absorption coefficient (α) was found greater than( 104)cm-1 for
all films , this means that the electronic transitions of allowed direct type and the absorption edge was
shifted toward the greater wavelength from (506.12)nm for the non-doped film and arrive to
(551.11)nm at 5%wtCd and no change of the electronic transitions type . The values of energy gap
were decreased from (2.45)eV for the non-doped film to (2.25)eV for the doped film at 5wt%(Cd) .
Also the values of (K) were shifted toward the greater wavelengths with increases the doping ratio, the
higher values of refractive index (n) were shifted toward the larger wavelength with increases in doping
ratio. Also The values of (€1) and (€2) are behave in the shape with increases in doping ratio . When
the thin film doped by (Pb) the energy gap values doesn't change and also the other constant for all
doping ratios.
Keywords
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