Akademik Veri Yönetim Sistemi
Materials Chemistry and Physics, cilt.303, 2023 (SCI-Expanded)
This study focused on the complex dielectric-constant (ε* = ε′-jε''), complex electrical-modulus (M* = Μ'+ Μ''), and ac electrical-conductivity (σac) of MS diodes with (Ag:ZnO)-PVP interlayer and the dependence of these parameters on frequency and voltage. The plots of the ε′ and ε'' versus Lnf reveal their variation depending on voltage at low frequencies, while these dependencies disappear at high frequencies. Such behavior of them is the result of Maxwell-Wagner and space-charge polarization occurring in the material along with the presence of interface traps (Dit) and a special distribution of them in the bandgap of the semiconductor. Contrarily, M′, M″, and σac parameters show voltage independence at low frequencies, while they vary with voltage at high frequencies. Besides, M″-V and M″-Lnf plots give a peak, and their position change with frequency and voltage, respectively. Observation of a peak in these plots corresponds to one relaxation process occurring in the material and the variation of peak position with voltage and frequency signifies the frequency and voltage dependence of this relaxation process. Additionally, complex-impedance (Ζ*) was exhibited as Ζ'/Z″-V and Ζ'/Z″-Lnf plots, and they show frequency independence at high-voltages while voltage independence at high-frequencies. Also, the single-semicircular arc of the Nyquist-diagrams of the structure supports the existence of one relaxation-process obtained from the M″-V/Lnf plots. As well as the dielectric parameters, Dit and relaxation times of these traps (τ) were determined by the admittance method and they show an increasing trend with voltage, while τ show a decline.