부산대학교 도서관

Au/PVC þ TCNQ/p-Si structure was fabricated and real and imaginary parts of the dielectric constant ( 3 0 , 3 00), loss tangent (tand), and the real and imaginary parts of the electric modulus (M0 , M00) and ac conductivity (sac) of this structure have been investigated in wide frequency a range of 1 kHze5 MHz at room temperature. All of these parameters were found strong function of frequency and voltage especially in the inversion and depletion regions at low frequencies due to interfacial polarization and charges at interface states (Nss). The decrease in 3 0 and 3 00 with increasing frequency indicated that the interfacial dipoles have less time to orient themselves in the direction of the alternate field. While the value of M0 increase with increasing frequency and reach a maximum, M00 shows a peak and the peak position shifts to higher frequency with increasing applied voltage. The ln(sac) vs ln(u) plot of the structure for 0.5 V has three linear regions (I, II and III) with different slopes which correspond to low, intermediate and high frequency ranges, respectively. Such behavior of ln(sac) vs ln(u) plot indicated that there are three different conduction mechanisms in the Au/PVC þ TCNQ/p-Si structure at room temperature.