Low- and high-frequency C-V characteristics of the contacts formed by adding a solution of the nonpolymeric organic compound on p-type Si substrate

Abstract

Al/quercetin/p-Si Schottky barrier diodes (SBDs) have been fabricated by adding a solution of the nonpolymeric organic compound quercetin in ethanol on top of p-Si substrate, and then evaporating the solvent. The quercetin/p-Si contact shows rectifying behaviour and the reverse curve exhibit a weak bias voltage dependence. Barrier height and ideality factor value of 0.86 and 1.06eV, respectively, for the device have been determined from the forward bias current-voltage (I-V)characteristics. The energy distribution of the interface state density located in the semiconductor band gap at quercetin/p-Si interface ranges from 2.12 x 10(12) cm(12) eV(-1) in (0.680-E-v)eV to 4.68 x 10(11) cm(-2) eV(-1) in (0.813-E-v) eV have been determined from the I-Vand the capacitance-voltage (C-V) characteristics (high-and low frequency). The interface state density has an exponential rise with bias from the midgap towards the top of the valence band. (C) 2007 Elsevier B.V. All rights reserved.