Investigation of the C-V characteristics that provides linearity in a large reverse bias region and the effects of series resistance, surface states and interlayer in Au/n-Si/Ag diodes


JOURNAL OF ALLOYS AND COMPOUNDS, vol.708, pp.464-469, 2017 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 708
  • Publication Date: 2017
  • Doi Number: 10.1016/j.jallcom.2017.03.013
  • Page Numbers: pp.464-469


The forward and reverse bias current-voltage (I-V), capacitance/conductance-voltage-frequency (C/G-V-f) characteristics of Au/n-Si/Ag Schottky barrier diodes (SBDs) were investigated by taking into account the effects of series resistance (R-s), surface states (N-ss) and interlayer at room temperature. It is quite obvious that both C-V and G/omega-V plots showed reverse, depletion, and accumulation regions in a way that resemble those of good metal-insulator-semiconductor (MIS) type SBDs rather than those of MS type SBDs. The high value of ideality factor n = 1.907) was attributed to the existence of a native SiO2 interlayer, N-ss and barrier inhomogeneity at M/S interface. The energy distribution profile of N-ss was obtained from the forward bias I-V data by taking into account the voltage dependence of the effective barrier height (Phi(B)), n and R-s. The frequency dependent profiles of N-ss and R-s were also obtained from C-V and G/omega-V data using Hill Colleman and Nicollian-Brews methods, respectively. The high values of C and G/omega at low frequency were attributed to the excess capacitance (C-ex.) and conductance (G(ex)./omega) resulting from the N-ss that could follow external ac signal. The value of Phi(B) obtained from the reverse bias C-V data for almost each frequency is higher than that of FB obtained from the forward bias I-V data. Such behavior of Phi(B) was attributed to the nature of measurement method. Experimental results confirmed that N-ss and R-s are quite effective on the electrical characteristics in the existence of native or deposited interlayer. (C) 2017 Elsevier B.V. All rights reserved.