The effect of (CeO2: PVC) thin interfacial film on the electrical features in Au/n-Si Schottky barrier diodes (SBDs) by using current-voltage measurements

In this paper, the cerium-oxide nanostructures (CeO2) were synthesized by using the hydrothermal method, and then Au-Si (MS), Au-PVC-Si (MPS1), and Au-(CeO2:PVC)-Si (MPS2) SBDs were fabricated to investigate organic interlayer effects on the main electrical properties and conduction-mechanisms (CMs). The structural/optical properties of the CeO2 nanopowders were analyzed using XRD, SEM, EDX, and UV-Vis spectroscopy methods. The average crystallite size of the nanopowders was estimated by Scherrer and Williamson-Hall method as 30 and 40 nm, respectively. SEM images show the nanoclusters have average size of 400 nm and consist of sphericalnanoparticles with a 40 nm average size. Nanostructures bandgap was calculated using a UV-Vis absorbance spectrum that is equal to 3.93 eV which has a blueshift compared to its bulk value (E-g = 2.9 eV) due to the quantum confinement effect. The CMs of these diodes were investigated using I-V characteristics by utilizing thermionic emission (TE), Cheungs, and Norde methods. The energy distribution of surface state (N-ss) was calculated from the forward bias I-F-V-F curve by considering voltage-dependent BH and n(V). The results show that polymeric interlayer can decrease N-ss by 1-2 orders and as a result improved the performance of MPS compared to MS diodes. Experimental results show that the presence of the interlayer in MPS diodes improved the main electrical parameters of MPS diodes compared to MS diode and also increased its rectification by 7 times compared to MS diode. The CCMs (current-transport/conduction mechanisms) were also investigated from the Ln(I-F)-Ln(V-F) curves which have three regions for MPS diodes and show I alpha V-m relation. The field-reduction coefficient (beta) was estimated from the reverse-bias Ln (I-R)-root V-R curves. While the CCM for MPS obeys the Poole-Frenkel emission and the MS diode obeys the Schottky emission (SE). Therefore, the polymer layer has changed the conduction mechanism of MPS diodes.