The interfacial properties of Au/n-4H-SiC structure with (Zn-doped PVA) interfacial layer

Abstract

The Au/n-4H-SiC (MS) type structure with (Zn-doped PVA) interfacial layer was prepared and the interfacial properties were investigated. The energy density distribution profile of the interface states (Nss) and their relaxation time (τ) and capture cross section (σp) of this structure was examined by using conduction method, which include a set of capacitance-voltage (C-V) and conductance-voltage (G/ω-V) measurements. The measured values of C and G/ω at 200 kHz were corrected to examine the Rs effect on them by using Nicollian-Brews method which indicated that Rs is more effective especially at accumulation region at high frequency and hence it must be taken into account in the calculations. Especially, at low frequency, the increase in C can arise from the existence of Nss at 4H-SiC/(Zn-doped PVA) interface. The profile of Nss and their τ values were obtained in the energy range of (Ec−0.26)-(Ec−0.83) eV. The values of Nss were found to be on the order of 1.72 × 1014 eV−1 cm−2 whereas their τ values changed from 1.47 × 10−4 to 4.22 × 10−5 s. According to the results, the obtained values are highly suitable for an electronic device such as MS type diodes with and without an interlayer and capacitors. All these results show that (Zn-doped PVA) polymer interlayer can be successfully used instead of insulator such as SiO2 grown by traditional methods such as thermal oxidation. Its low cost, low molecular weight, high strength electric field, flexibility, and easy production methods such as sol-gel and electro-spinning which need not more energy consumption at room temperature are of some advantages.