In this work, the frequency dependent electrical characteristics of Al/SiO₂/SiNWs/n-Si MOS capacitors were investigated. The electrical properties of the capacitors were calculated from the capacitance-voltage (C-V) and conductance-voltage (G_m/ɷ-V) measurements for several frequencies ranging from 50kHz to 1MHz. Our experimental results showed that both frequency and voltage variations had a significant impact on the C-V and G_m/ɷ-V characteristics. The C-V characteristics were found to decrease with an increase in the applied voltage frequency due to the distribution of the interface states (N _it) within the oxide layer. The G_m /ɷ-V characteristics were also found to have peaks and the peaks increased with an increase in the applied voltage frequency except for 50kHz and 100kHz. This was caused by the existence of series resistance (R_s) and N_it. We have also studied the frequency dependence on the electrical parameters such as R_s, N _it, doping concentration (N_D), and barrier height (Ф_B). The values of R _s were found to decrease with increasing frequency, while the values of N_it, N_D and (Ф_B) were also found to increase with increasing applied frequency.

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