High-Performance, sub-2 volts TiO2 thin film transistors enabled by ultrathin ZrO2 gate dielectrics

We report on, for the first time, high-performance, sub-2 volts TiO
2
thin film transistors (TFTs) enabled by ultrathin ZrO
2
gate dielectrics. The effect of ZrO
2
thickness on TFT performance is systematically studied. It is found that the TFT performances are enhanced with the reduced ZrO
2
thickness, benefiting from the increased gate oxide capacitance
$(\mathrm{C}_{\text{ox}})$
. The TiO
2
TFTs with an ultrathin ZrO
2
dielectric of 5 nm show a high
$\mathrm{I}_{\text{on}}/\mathrm{I}_{\text{off}}$
of
$7.7\times 10^{7}$
and a nearly ideal SS of 72 mV under an ultra-low voltage of 2 V. The highperformance, sub-2 volts TiO
2
TFTs show great promise for future portable electronic applications.