Comparative study of InGaZnO thin-film transistors with single and dual NbLaO gate dielectric layers

Amorphous InGaZnO thin-film transistor using NbLaO gate dielectric with low La content is prepared and shows acceptable performance with a carrier mobility of 15.7 cm(2)V(-1)s(-1). Moreover, the gate-dielectric/InGaZnO interface can he improved by inserting a buffer layer of NhLaO with higher La content between the gate dielectric and InGaZnO layer, thus resulting in better device performance in terms of higher carrier mobility (28.5 cm(2)V(-1)s(-1)), lower threshold voltage (2.5 V), higher on current (252 A) and smaller hysteresis (0.4 V). Therefore, the HNbLaO is a potential candidate as buffer layer for improving the electrical performance of InGaZnO thin-film transistor.