Mechanism of Extraordinary High Mobility in Multilayered Amorphous Oxide Thin Film Transistor

Abstract

Amorphous oxide-based thin-film transistors (TFTs) have been applied to display and various next-generation applications. The amorphous oxide thin film has exhibited a higher electrical mobility and stability characteristics in recent decades. A multilayer thin-film structure has been fabricated and analyzed using amorphous Si-In-Zn-O (a-SIZO) and amorphous Si-Zn-Sn-O (a-SZTO) materials. The a-SIZO had a current value of more than 10⁻³ A without off-current (like metal) when fabricated as a single layer of thin film. The fabricated bilayer TFT shows an improved field effect mobility upon inserting the a-SIZO conductive semiconductor layer at the bottom. With the aforementioned architecture, we have achieved a mobility that is higher than 160 cm²/V·s with a <formula> <tex>$V_{th}$</tex> </formula> shift of 1.19 V under negative bias temperature stress (NBTS) for an amorphous-based semiconducting multilayer TFT. IEEE