Top-Gate Low-Threshold Voltage $p\hbox{-}\hbox{Cu}_{2} \hbox{O}$ Thin-Film Transistor Grown on $\hbox{SiO}_{2}/ \hbox{Si}$ Substrate Using a High-$\kappa$ HfON Gate Dielectric

Copper oxide (Cu
x
O) thin films were grown on SiO
₂
/Si substrate by pulsed laser deposition under different substrate temperatures. Top-gate Cu
x
O semiconductor thin-film transistors (TFTs) were fabricated with high- κ HfON as gate dielectric. The performance of Cu
₂
O TFTs was improved due to increased Hall mobility resulting from the decreased scattering of both the ionized defects and the grain boundary for Cu
₂
O channel films. The
p
-channel pure polycrystalline Cu
₂
O TFTs (
W
/
L
= 500 μm/20 μm) exhibited a low threshold voltage of -0.8 V, an on-off current ratio of 3 x 10
⁶
, a saturation mobility of 4.3 cm
²
/ V s, and a subthreshold swing of 0.18 V/decade.