The synthesis of 4,4′-(9,9-dioctyl-9H-fluorene-2,7-diyl)bis(N,N-diphenylaniline) organic semiconductor and use of it as an interlayer on Au/n-Si diode

In the present study, firstly, a 4,4′-(9,9-dioctyl-9H-fluorene-2,7-diyl)bis(N,N-diphenylaniline) (FC) organic compound was synthesized and its structural and optical characterization were carried. Then, the effect on the device of the FC thin film prepared between n-type silicon substrate and gold metal by the spin coating technique was reported. The ideality factor (n), barrier height (Φ B) and series resistance (Rs) values of the prepared structure from the I-V data have been found at 1.08, 0.78 eV and 240 Ω at room temperature (300 K), respectively. According to the Gaussian distribution of the barrier height obtained from the various temperature ranges (220–380 K), the Φ b and A* values from the ordinate intercept and the slope of the modified Richardson curve of ln(I0/T2)-(q2σs2/2k2T2) versus 1/T plot which has been found to be 0.97 eV and 114 A/cm2K2, respectively. Results indicate that the high barrier height is achieved for the Au/FC/n-Si metal–organic layer-semiconductor diode as compared to the Au/n-Si metal–semiconductor (MS) diode.