Low-Voltage High-Stability Indium–Zinc Oxide Thin-Film Transistor Gated by Anodized Neodymium-Doped Aluminum

Neodymium-doped aluminum (Al-Nd) was used as a gate electrode and was anodized, forming a layer of Nd:Al
₂
O
₃
as the dielectric for indium-zinc oxide (IZO) thin-film transistors (TFTs). The Nd:Al
₂
O
₃
showed high capacitance (110 nF/cm
²
), high breakdown field (>;6 MV/cm), and low leakage current (<; 10
^-7
A/cm
²
at 2.0 MV/cm) without hillocks when annealed at 300°C. The TFT showed a low operating voltage of 3 V, a low off current of ~10
^-13
A, a high mobility of 13.7 cm
²
· V
^-1
· s
^-1
, and excellent electrical stability because of the good interface coupling between Nd:Al
₂
O
₃
and IZO, resulting from the low electronegativities of Al and Nd.