Dielectric Relaxation in CdxInSe9-x Chalcogenide Thin Films

Abstract

The effect of temperature (273-493 K), frequency (102-105 Hz) and
composition on the dielectric response of the CdxInSe9-x (x= 1,2,3,4 and 5)
Chalcogenide glass system was studied. The experimental results indicate that
dielectric constant (real permittivity), dielectric loss and loss angle έ, ε'' and tan
δ, increase with increasing temperature. The complex impedance (Z) was
measured over the same temperature and frequency ranges. All samples gave a
semicircle arc originating at the origin point. This indicates that each
composition can be described only by one bulk resistance Rb and one capacity
Cb, both parallels combined. The centre below the real axis indicates the
relaxation behaviour of the system. The dielectric dispersion is characterized by
the distribution of the relaxation time induced by polarized species contribution
(orientational, interfacial, electronic and ionic dipoles). The free energy (ΔF)
and the enthalpy (ΔH) of the dipoles are estimated for the investigated
compositions.