Electrical and dielectric properties of Al/(PVP: Zn-TeO_2)/ p-Si heterojunction structures using current-voltage (I-V) and impedance-frequency (Z-f) measurements

摘要

For the investigation of the influence of (PVP: Zn-TeO_2) interphase layer on the electrophysical parameters, Al/p-Si structures with/ without (PVP: Zn-TeO_2) interlayer grown by spin-coating technique and then these factors were studied by I-V and Z-f measurements. First, the Field Emission Scanning Electron Microscopy (FE-SEM), X-ray Diffraction (XRD), Energy Dispersive X-ray Spectroscopy (EDS), and UV-Vis analyses techniques were performed to investigate the morphology, purity determination, and the optical properties of the nanostructures, respectively. Second, I-V measurements and Z-f were performed at ±3 and 1.5 V (at 100 Hz-1 MHz), respectively. The values of ideality factor (n), barrier height (BH:Φ_B), and series resistance (R_s) of them were obtained using various methods such as thermionic emission, Cheung's and Norde functions and compared. The energy dependence of surface states (N_(ss)) were extracted from the forward bias I-V measurements by assuming the voltage dependence of BH and n. The frequency-dependence profiles of dielectric constant (ε')/loss (ε"), and ac electrical conductivity (σ_(ac)) were extracted from the Z-f measurements. Experimental results show that (PVP: Zn-TeO_2) interlayer leads to an increase in the ε', e", BH, R_(sh), and decrease in N_(ss). Therefore, Al/(PVP: Zn-TeO_2)/p-Si structures can be used as an electronic part in nanoscale instead of MS structures.