Investigation of current‐voltage characteristics and current conduction mechanisms in composites of polyvinyl alcohol and bismuth oxide

Abstract

Temperature dependent current-voltage (I-V) measurements of Au/Polyvinyl Alcohol 1 Bi 2 O 3 /n-Si structure were conducted between 100 and 350 K for investigating the temperature dependence of I-V characteristics and current conduction mechanisms in the structure. Series resistance of the structure is calculated using Ohm's law and Cheungs' method. Ideality factor (n) and zero-bias barrier height (U Bo ) were obtained considering thermionic emission theory. From 100 to 350 K, n changed from 32.1 to 3.54, and U Bo changed from 0.27 to 0.99 eV. Obtained temperature dependent values of n and U Bo suggested that thermionic emission is not the dominant current conduction mechanism. Therefore, Ln(I)-Ln(V) curves of the studied structure were plotted for investigating current conduction mechanisms in the structure and current flow is explained considering space charge limited current. Moreover, density of interface states (D it ) in the structure were calculated and its temperature dependence was investigated such that D it values are reduced to the order of $10 13 eV 21 cm 22 from $10 14 eV 21 cm 22 with increasing temperature.

Study of barrier height inhomogeneity at zinc oxide/polymer:fullerene interface in polymer solar cells

“…This temperature dependence of the barrier heights indicates presence of inhomogeneous barrier height at ZnO/P3HT:PCBM interface and deviation from thermionic emission theory. Similar results were also reported in other metal‐semiconductor systems like Al/p‐Si, In/p‐Si, Ni/n‐GaAs/In, Au/n‐Si, Al/PANI/Nd 2 O 3 :Al 2 O 3, and Au/PVA + Bi 2 O 3 /n‐Si . Durmus et al in their work on Au/n‐Si Schottky barrier also investigated the effect of distribution of interface traps and their restructuring and reordering under the effect of temperature for larger values on ideality factor.…”

The effect of Mo-doped PVC+TCNQ interfacial layer on the electrical properties of Au/PVC+TCNQ/p-Si structures at room temperature

“…The I s , n and Φ Bo values determined from the forward bias ln I-V plots are 3.11 Â 10 À 9 A, 2.93, and 0.78 eV for Au/PVCþTCNQ/p-Si and 6.66 Â 10 À 6 A, 5.76, and 0.57 eV for Au/Mo-doped (PVCþ TCNQ)/p-Si structures, respectively, at room temperature and they are also shown in Table 1. These high values of n for both diodes can be attributed to the particular density distribution of surface states (N ss ) localized at M/S interface, the thickness of interfacial layer and its inhomogeneity, and the nature of barrier height at M/S interface [23][24][25][26][27][28][29][30]. Also, the image-force effect, recombination-generation, and tunneling via interface states may be possible mechanisms that lead to decrease in n value [24,31].…”