Implementing Room‐Temperature Fabrication of Flexible Amorphous Sn–Si–O TFTs via Defect Control

Abstract

AbstractRecently, amorphous oxide semiconductors (AOSs) have attracted much attention owing to their various advantages. The intrinsic nature of AOSs enables to achieve high‐performance thin‐film transistors (TFTs) using low‐temperature process, which would be a strong point for next‐generation flexible electronics. However, most AOS TFTs still require postannealing treatments (>300 °C) for structural relaxation to suppress defects, which lead to the issue of thermal resistance of plastic substrates. Therefore, a strategy for obtaining both low‐temperature process and defect suppression is highly demanded for flexible electronics. To solve the former issue, a Sn–Si–O system is proposed in this paper. It is clarified that Si cations play the roles of amorphousizing SnO2 and suppressing carrier concentration. As a result, room‐temperature fabricable flexible Sn–Si–O TFTs with high mobility and high reliability are demonstrated. It is also suggested that obtaining a rigid film structure is quite important to fabricate high performance TFTs without any further postannealing treatment. The obtained saturation mobility (μsat) and on/off ratio are 7.59 cm2 V−1 s−1 and 1.59 × 107, respectively. This work suggests that amorphous Si doped SnO2 has the potential for the application to the flexible driving backplane in display industry.