The field dependence of dielectric parameters in chalcogenide glassy systems

The field influence on the dielectric parameters of nonmodified and modified As₂Se₃ thin films is studied. The a-As₂Se₃ layers with thickness d∼1.0 μm were obtained by the method of joint high-frequency (HF) atomization in the electromagnetic field at a frequency of 13.6 MHz onto silicate substrates. The samples had sandwich configuration with aluminium electrodes and contact area of 15.0 mm². Dispersion of dielectric parameters: dielectric constant ε, and the dielectric loss factor, tgδ were calculated from the dark current isothermal relaxation curves I(t) registered at different values of electrical field. The dependences obtained are explained in terms of structure peculiarities. The addition of Bi gives birth to clusters which are responsible for donor impurities in the band gap.