Capacitance–voltage, conductance-voltage and dielectric properties of the Al/GO/p-Si semiconductor structures in wide frequency range
摘要
In this study, the capacitance voltage (C–V), conductance-voltage (G/ω–V), series resistance–voltage (RS–V) characteristics, interface state densities and dielectric properties of Al/GO/p-type Si semiconductor structures were investigated in the frequency range of 100 to 1000 kHz by 100 kHz steps depending on the frequency at room temperature. Using the spin coating method, the graphene oxide (GO) solution was coated as a thin film layer on the front surface of the p-type Si semiconductor. The interface-state densities (NSS) of the Al/p-Si structures with GO interlayer decreased exponentially with bias from 3.93 × 1013 cm−2 eV−1 (for 100 kHz) to 5.07 × 1011 cm−2 eV−1 (for 1000) kHz. Furthermore, dielectric characteristics as known dielectric constant (ε′), dielectric loss (ε′′), loss tangent (tanδ), ac/dc electrical conductivity (σac, σdc), electrical modulus (M′, M′′) and complex impedance values (Z′, Z″) were obtained using C-V and G/ω-V measurements. Experimental results showed that dielectric values such as ε′, ε′′, tanδ, σac, σdc, lnσac and lnσdc generally decreased with increasing frequency, while dielectric values such as M′, M′′ Z′ and Z′′ increased with increasing frequency. Accordingly, in the range of 100 kHz and 1 MHz, the values of ε′, ε′′, and σac, changed from 1.647 to 1.154, 54.922 to 1.422 and 3.052 × 10–9 to 7.905 × 10–10, respectively. Also, at the same frequencies, the electric modulus values M′ and M′′ changed from 1.0 × 10–3 to 3.44 × 10–1 and 1.8 × 10–2 to 4.24 × 10–1, respectively.