One-Volt IGZO Thin-Film Transistors With Ultra-Thin, Solution-Processed Al_xO_y Gate Dielectric

Abstract

Indium-gallium-zinc-oxide thin-film transistors (TFTs) with solution-processed, high-capacitance Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">y</sub> gate dielectrics have been fabricated at room temperature. The morphology and electrical properties of the anodized, ultra-thin AlxOy film have been studied. Several anodization voltages were used to create the gate dielectrics and the results showed that the TFTs gated with aluminum oxide anodized at 2.3 V (~3 nm) exhibited the best performance. The TFTs operate at an ultra-low voltage of 1 V with a high current on/off ratio >10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</sup> and a subthreshold swing (SS) as low as 68 mV/dec, which is very close to the theoretical limit of SS at 300 K. As a result, the presented devices possess a great potential for low-power electronics.