Abstract
Switching characteristics of copper oxide (Cu
2
O) thin-film transistors (TFTs) were enhanced by buffering both sides of the channel with a thin layer of sputtered molybdenum trioxide (MoO
3
). On the top side, the thin MoO
3
layer was capable of controlling the back-channel phase by forming a high-resistance surface-path and hence reducing the drain off-current. While on the bottom side, the MoO
3
film worked as a passivation layer at the (semiconductor/dielectric) interface which helped in reducing the interfacial states density
D
it
by one order of magnitude. By optimizing the nitrogen doping conditions and harnessing the bilayer channel scheme, switching characteristics were enhanced even more. Our best double-buffered bilayer TFT achieved a subthreshold swing of 0.14 V dec
−1
, an on/off current ratio (
I
on
/
I
off
) of 2.7 × 10
6
, and a field-effect mobility (
μ
FE
) of 0.11 cm
2
V
−1
s
−1
, a considerable enhancement in performance compared to that of non-doped non-buffered Cu
2
O TFTs.