1 research outputs found
Optimization of a Solution-Processed SiO<sub>2</sub> Gate Insulator by Plasma Treatment for Zinc Oxide Thin Film Transistors
We report on the optimization of
the plasma treatment conditions
for a solution-processed silicon dioxide gate insulator for application
in zinc oxide thin film transistors (TFTs). The SiO<sub>2</sub> layer
was formed by spin coating a perhydropolysilazane (PHPS) precursor.
This thin film was subsequently thermally annealed, followed by exposure
to an oxygen plasma, to form an insulating (leakage current density
of ∼10<sup>−7</sup> A/cm<sup>2</sup>) SiO<sub>2</sub> layer. Optimized ZnO TFTs (40 W plasma treatment of the gate insulator
for 10 s) possessed a carrier mobility of 3.2 cm<sup>2</sup>/(V s),
an on/off ratio of ∼10<sup>7</sup>, a threshold voltage of
−1.3 V, and a subthreshold swing of 0.2 V/decade. In addition,
long-term exposure (150 min) of the pre-annealed PHPS to the oxygen
plasma enabled the maximum processing temperature to be reduced from
180 to 150 °C. The resulting ZnO TFT exhibited a carrier mobility
of 1.3 cm<sup>2</sup>/(V s) and on/off ratio of ∼10<sup>7</sup>