Evaluation of Electric and Dielectric Properties of Metal–Semiconductor Structures With 2% GC-Doped-(Ca3Co4Ga0.001O x ) Interlayer

Abstract

Electrical and dielectric properties of Au/n-Si metal–semiconductor structures with high dielectric have been examined by capacitance/conductance–voltage ( ${C}/{G}$ – ${V}$ ) measurements in the frequency range of 5–500 kHz at room temperature. Voltage-dependent profiles of interface states ( ${N}_{\text {ss}}$ ) and resistance ( ${R}_{i}$ ) were extracted from the C and G data using the low–high-frequency capacitance and Nicollian–Brews methods, respectively. The real and imaginary components of the complex dielectric constant ( $\varepsilon ^\prime $ , $\varepsilon ^{\prime \prime }$ ), electric modulus ( ${M}^\prime $ and ${M}^{\prime \prime }$ ), and ac conductivity ( $\sigma _{\mathsf {ac}}$ ) were calculated from the ${C}$ and ${G}$ data. All parameters have a strong relation with frequency and voltage, especially at low frequencies due to Maxwell–Wagner relaxation and ${N}_{\mathsf {ss}}$ . The observed peaks in the ${N}_{\mathsf {ss}}$ – ${V}$ and ${R}_{i}$ – ${V}$ plots can be ascribed by the special distribution of ${N}_{\mathsf {ss}}$ at M/S interface. These results confirmed that [2% graphene cobalt-doped (Ca3CO4Ga0.001O x )] interlayer has high-dielectric constant and can be used an interlayer instead of the traditional SiO2 at M/S interface to increase their capacitance or more charges/energy storage and reduce both the values of ${N}_{\mathsf {ss}}$ and series resistance ( ${R}_{s}$ ). The values of $\sigma $ are almost constant at lower–intermediate frequencies, but they start to increase at high frequencies that are corresponding to the dc and ac conductivity, respectively.