High-performance low voltage operation of indium zinc tin oxide thin film transistors using chemically derived sodium ?-alumina dielectric

Abstract

We present high performance, low voltage (< 3 V) operation of thin film transistors (TFTs) with indium zinc tin oxide (IZTO: In<inf>4</inf>Sn<inf>4</inf>ZnO<inf>15</inf>)-semiconductor. The film of IZTO was fabricated via low-temperature (200 °C) solution combustion processing without incorporating an external fuel. As 2-methoxyethanol is a widely used organic solvent due to its high dissolution capability, serve the purpose of both the solvent and the fuel. On quantification from the balanced redox reaction, 0.3% of 2-methoxyethanol assisted for the action of fuel and helped in the formation of metal oxide, and the rest (99.7%) served the purpose of being dissolution medium. The balanced redox chemistry yielded a significant fraction of (56.5%) metal oxide at 200 °C confirmed via high-resolution oxygen 1 y spectrum. Further, the chemically derived thin film of sodium ss-alumina with a dielectric constant of ~ 21, while annealing at 350 °C incorporated in the TFT for the realization of low voltage operation. The performance assessment is systematically carried out both silicon dioxide (SiO<inf>2</inf>) and sodium ss-alumina and found that the TFTs with SiO<inf>2</inf> and IZTO exhibited a saturation mobility (µ^), I<inf>on</inf>/I<inf>off</inf> ratio and the threshold voltage (Vth) of 0.50 ± 0.02 cm2 V-1 s-1, 1.25 x 104 and 6.6 ± 0.79 V respectively. While changing the dielectric to sodium ss-alumina presented a µ<inf>sat</inf>, I<inf>on</inf>/I<inf>off</inf> ratio and V<inf>th</inf> of 4.21 ± 0.18 cm2 V-1 s-1, 1.4 x 102 and 0.47 ± 0.08 V respectively. © Springer Science+Business Media, LLC, part of Springer Nature 2019.