Low-voltage antimony-doped SnO2 nanowire transparent transistors gated by microporous SiO2-based proton conductors

A battery drivable low-voltage transparent lightly antimony(Sb)-doped SnO₂ nanowire electric-double-layer (EDL) field-effect transistor (FET) is fabricated on an ITO glass substrate at room temperature. An ultralow operation voltage of 1 V is obtained on account of untralarge specific gate capacitance (～ 2.14 μF/cm²) directly bound up with mobile ions-induced EDL (sandwiched between top electrode and bottom electrode) effect. The transparent FET shows excellent electric characteristics with a field-effect mobility of 54.43 cm²/V·s, current on/off ration of 2× 10⁴, and subthreshold gate voltage swing (S=d V_gs/d(log I_ds)) of 140 mV/decade. The threshold voltage V_th (0.1 V) is estimated which indicates that SnO₂ namowire transistor operates in an n-type enhanced mode. Such a low-voltage transparent nanowire transistor gated by microporous SiO₂-based solid electrolyte is very promising for battery-powered portable nanoscale sensor.