Evaluation of electrical parameters of Ni/n-type Si Schottky barrier diodes using polyvinyl alcohol (PVA) as an interfacial layer

The electrical properties and transport mechanisms ofNi/PVA/n-Si MIS type SBDs was investigated using I-V measurements which were performed at room temperature. The fabricated MIS SBD exhibited good rectification ratio with low leakage current when compared to Ni/n-Si MS SBD. The evaluated SBH of MIS type SBDs using PVA as an interfacial layer was found to be 0.80 eV (I-V), 0.88 eV (Cheung), 0.81 eV (Norde) improved when compared to MS structure with 0.70 eV (I-V), 0.74eV (Cheung) and 0.72eV (Norde). The ideality factor (n) values were calculated using thermionic emission (TE) theory and were found to be 1.09 for the MS and 1.35 for the MIS SBDs. The RS, ‘n’ values were extracted for the MIS and MS SBDs using Cheung functions and were calculated as 171 Ω, 1.24 and 3345 Ω, 1.43 respectively. The series resistance (RS) values were also extracted from H(I) versus I plot and were found to be 459 Ω for MIS SBD and 15,669 Ω for the MS SBD. Furthermore, the surface potential versus forward voltage plot of the MIS SBDs yielded a SBH of 0.77 eV which is higher than 0.68 eV achieved for MS SBD. It can be concluded that the deliberately deposited PVA as an insulating layer at the Ni/n-Si interface remarkably varied the electrical properties of the fabricated Ni/PVA/n-Si MIS SBDs.