Nearly Reversible Threshold Voltage Shifts with Low-Voltage Bias Stress in Solution-Processed In2O3 Thin-Film Transistors

N-channel thin-film transistors (TFTs) made of solution-processed In
₂
O
₃
were fabricated and electrical tested for device reliability. While the TFTs give a threshold voltage V
_th
of 0.6 V for low-voltage operation, experimental results show that V
_th
shifts over time even when the gate biasing voltage is at 3 V. V
_th
can increase to about 2 V after about one hour. The change in V
_th
is nearly reversible if there is a long enough relaxation time. When the gate biasing voltage is -3 V, V
_th
changes from 0.6 V to -0.6 V and the V
_th
shift is less reversible. Such phenomena are expected to be due to the interface traps in the solution-processed In
₂
O
₃
.