Nearly Reversible Threshold Voltage Shifts with Low-Voltage Bias Stress in Solution-Processed In 2 O 3 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 .