Investigation of electrical and admittance analysis of Au/Thiophene/n-Si structure at room temperature

In this study, the Au/n-Si/Au-Sb and Au/Thiophene/n-Si/Au-Sb devices were fabricated at same conditions and electrical/dielectric properties were studied. The electrical measurements showed that the presence of the thiophene interface layer increased the rectification ratio (RR), approximately 2.5 times. Furthermore, the ideality factor (n) value increased from 1.6 to 2.2, the series resistance (R-s) decreased. The capacitance-voltage (C-V) curves indicated peaks for each frequency in accumulation region at about 0.2 V and the peak values decreased from 6.4 x 10(-10) F to 4.3 x 10(-11) F with increasing frequency. The conductance (G/omega) values decreased with increasing frequency. On the other hand, while the donor concentration (N-D) is gradually decreased from 7.12 x 10(14) cm(-3) to 6.05 x 10(14) cm(-3) with increasing frequency, the zero-bias barrier height (Phi(Bo)) increased from 0.330 eV to 0.627 eV. However, the Fermi energy (E-F) has nearly not effected. The results showed that the thiophene can be used as effective interface material for interface engineering.