Abstract
High performance ZnO nanowire field effect transistors (NW-FETs) were fabricated using a nanoscopic self-assembled organic gate insulator and characterized in terms of conventional device performance metrics. To optimize device performance and understand the effects of interface properties, devices were fabricated with both Al and Au/Ti source/drain contacts, and device electrical properties were characterized following annealing and ozone treatment. Ozone-treated single ZnO NW-FETs with Al contacts exhibited an on-current (I-on) of similar to 4 mu A at 0.9 V-gs and 1.0 V-ds, a threshold voltage (V-th) of 0.2 V, a subthreshold slope (S) of similar to 130 mV/ decade, an on - off current ratio (I-on: I-off) of similar to 10(7), and a field effect mobility (mu(eff)) of similar to 1175 cm(2) V-1 s(-1). In addition, ozone-treated ZnO NW-FETs consistently retained the enhanced device performance metrics after SiO2 passivation. A 2D device simulation was performed to explain the enhanced device performance in terms of changes in interfacial trap and fixed charge densities.
Date of this Version
April 2007