Dielectric, modulus and conductivity studies of Au/PVP/n-Si (MPS) structure in the wide range of frequency and voltage at room temperature

Both the real-imaginary components of complex dielectric permittivity and electric modulus, and ac conductivity of Au/PVP/n-Si (MPS) structures were analyzed by admittance spectroscopy technique between 1 and 500kHz, -3 and 5V. The polyvinylpyrrolidone (PVP) polymer layer was deposited on n-Si wafer by spin-coating technique. The epsilon, epsilon, M, M and sigma(ac) values were calculated from the admittance measurements and they are quite function of frequency and voltage due to a special distribution of surface states at PVP/n-Si interface, interfacial/dipole polarizations at low frequencies. While the epsilon and epsilon values decrease as frequency increases, the sigma(ac), M and M increase. The ln(sigma(ac)) vs ln() plot for 3V has two linear region between 1 and 20kHz, 30 and 500kHz frequencies, respectively. The obtained 0.033 slope value for low-frequencies which corresponding to dc conductivity and it is almost independent of frequency, but it obtained 0.46 for high-frequencies which corresponding ac conductivity and is strong function of frequency due to the increase eddy current. As a result, the prepared MPS structure can be used as charges/energy storage device due to the dielectric property of the PVP polymer layer.