Tailoring Threshold Voltage in Indium‐Zinc‐Oxide Thin‐Film Transistors by Inserting a 2‐(4‐Biphenylyl)‐5‐(4‐tert‐butylphenyl)‐1,3,4‐oxadiazole Buffer Layer

Abstract

The authors investigate solution‐processed indium‐zinc‐oxide (IZO) thin‐film transistors (TFTs) into which the authors insert a 2‐(4‐biphenylyl)‐5‐(4‐tert‐butylphenyl)‐1,3,4‐oxadiazole (PBD) buffer layer. The proposed buffer layer tune an efficient energy level between the oxide semiconducting channel and metal electrode by increasing the charge extraction, thereby shifting the threshold voltage from 3.52 V to 8.96 V and enhancing overall device performance. In particular, based on 10‐nm‐thick PBD film, the IZO TFTs exhibit an excellent result and show a field‐effect mobility of 2.07 cm2 Vs−1, a high Ion/Ioff ratio of 1.3 × 107, a threshold voltage of 6.36 V, and a subthreshold swing of 0.53 V dec−1.