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

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 cm
²
/
$\text{V}\cdot \text{s}$
with a
${V}_{\textit {th}}$
shift of 1.19 V under negative bias temperature stress (NBTS) for an amorphous-based semiconducting multilayer TFT.