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

Abstract

Recently, 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 degrees 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 (mu(sat)) and on/off ratio are 7.59 cm(2) V-1 s(-1) and 1.59 x 10(7), respectively. This work suggests that amorphous Si doped SnO2 has the potential for the application to the flexible driving backplane in display industry.