Low-Temperature Fabrication of Nontoxic Indium Oxide Nanofibers and Their Application in Field-Effect Transistors

In this letter, the water-induced (WI) In
₂
O
₃
nanofibers were prepared by electrospinning using poly(vinyl alcohol) as polymer. The field effect transistors (FETs) based on In
₂
O
₃
nanofibers were integrated, and the annealing dependence of the FETs performance was investigated. It is found that the FET based on WI In
₂
O
₃
nanofibers annealed at 380°C for 1 h (In
₂
O
₃
-380-1h) exhibits a field-effect mobility (μ
_FE
) of 1.53 cm
²
/Vs, and an ON/ OFF current ratio (I
_ON
/I
_OFF
) of ~8 × 10
⁴
. Interestingly, the electrical performance of the FET based on WI In
₂
O
₃
nanofibers annealed at 280°C for 10 h (In
₂
O
₃
-280-10h) is comparable with the FET based on In
₂
O
₃
-380-1h. To further improve the electrical performance of the FETs processed at low temperature, the FET based on In
₂
O
₃
-280-10h as the channel and the aqueous-route derived ZrO
_x
as dielectric was integrated. The optimized FET exhibits a μ
_FE
of 5.8 cm
²
/Vs, an I
_ON
/I
_OFF
of ~10
⁷
, and a subthreshold swing (SS) of 150 mV/decade. This nontoxic and fully water-inducement approach is highly expected for the fabrication of low-temperature and flexible circuitry.