Investigation on the effect of interface state density and series resistance in Ag/Ge-NW/Si (MS) device synthesized by glancing angle deposition technique

Abstract

Catalyst-free Ge-nanowire (NW) was synthesized using the glancing angle deposition (GLAD) technique integrated into an electron beam evaporator. The study is mainly focussed on the analysis of frequency and voltage dependence of the capacitance–voltage (C-V) and conductance-voltage (G/ω-V) characteristics of Ag/Ge-NW/Si device over a wide range of frequency (200 kHz−2 MHz) and voltage (−5 V to +5 V) at room temperature. FEG-SEM image confirmed the successful growth of vertically oriented Ge-NW on Si substrate. Both C-V and G/ω -V values showed wide dispersion in the depletion, inversion, and accumulation region due to interface state density (Dit) and series resistance (Rs). The voltage and frequency-dependent Dit and Rs were calculated from the Hill-Coleman and Nicollian-Brews methods, respectively. It is observed that the overall Dit and Rs for the device decrease with an increase in the frequency at different voltages.