Fabrication of indium-tin-oxide thin-film transistor using anodization

Thin-film transistors based on anodized indium-tin-oxide (ITO) active layer and anodic tantalum oxide (Ta
₂
O
₅
) gate dielectric were investigated. The electrical and optical properties of ITO film can be affected by an anodization treatment. The anodized ITO TFT shows an on/off current ratio of 10
⁸
, a saturation mobility of 28.8 cm
²
V
^-1
s
^-1
, a subthreshold swing of 0.51 V/dec, and a threshold voltage of -2.5 V It is also shown that the ITO film shows higher resistivity and porous structure after anodized at various anodization voltage V
_a
. Also, the surface of the ITO film becomes less porous and the resistivity rises as the anodization current density J
_a
increases.