Solution-Processed ZTO TFTs With Recessed Gate and Low Operating Voltage

We demonstrate solution-processed zinc tin oxide thin-film transistors (TFTs) with a patterned-gate configuration. High-
$k$
and solution-processed zirconium oxide
$(\hbox{ZrO}_{2})$
was employed to lower down the operating voltage. Devices with recessed and nonrecessed gate electrodes were compared to study the influence of gate surface relief on the performance of the solution-processed thin films. The TFTs with the recessed gate electrode operate at 5 V and have a threshold voltage of
$\sim$
1 V, subthreshold slope of
$\sim$
0.23 V/dec, saturation mobility of 2.5
$\hbox{cm}^{2}/\hbox{V} \cdot \hbox{s}$
, and on/off current ratio of
$> \hbox{10}^{6}$
.