Characteristics of Elevated-Metal Metal-Oxide Thin-Film Transistors Based on Indium-Tin-Zinc Oxide

Abstract

Based on the distinct effects of oxidizing thermal annealing on the properties of zinc oxide and indium-gallium-zinc oxide (IGZO) under covers of different gas-permeabilities, the elevated-metal metal-oxide (EMMO) thin-film transistor (TFT) architecture has been proposed and demonstrated using IGZO as the channel material. However, the speculation that the EMMO architecture is more generally applicable to semiconducting metal oxides other than IGZO has yet to be verified. Presently reported is an EMMO TFT with a modified structure employing indium-tin-zinc oxide as the channel material. The resulting TFT exhibited good performance metrics: a relatively higher field-effect mobility of 23.2 ± 0.8 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /Vs, an ON/OFF current ratio of at least 3.1 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">10</sup> , a pseudo subthreshold slope of 165 ± 15 mV/decade,a width-normalized OFF-state current of at most 8.1 ×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-19</sup> A/μm, and robust stability against gate-bias stress.