Abstract We describe how the off-state current (Ioff) property of amorphous InGaZnO (a-IGZO) thin-film transistors is caused by trap-assisted tunneling (TAT) by using a two-dimensional device simulation software application (Atlas 2 D, Silvaco). We found that Ioff can be increased by controlling the bandgap energy (EG) and the effective mass of electron (me) of a-IGZO transistors. When me was increased from 0.32 to 0.38 mo (mass of a free electron), the point at which Ioff started to increase in the region of negative gate voltage (VGS) shifted from −4.7 to −7.4 V. In addition, when EG was changed from 3.05 to 3.2 eV, the average value of Ioff changed from 3.13 × 10−13 to 2.4 × 10−14 A. This implies that EG and me influence the increase in Ioff in a-IGZO TFTs because of the difficulty associated with TAT.

中文翻译：

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陷阱辅助隧穿对a-InGaZnO薄膜晶体管截止电流特性的影响

摘要 我们描述了非晶 InGaZnO (a-IGZO) 薄膜晶体管的断态电流 (Ioff) 特性是如何通过使用二维器件模拟软件应用程序 (Atlas 2 D,席尔瓦科）。我们发现可以通过控制 a-IGZO 晶体管的带隙能量 (EG) 和有效电子质量 (me) 来增加 Ioff。当 me 从 0.32 增加到 0.38 mo（自由电子的质量）时，负栅极电压 (VGS) 区域中 Ioff 开始增加的点从 -4.7 V 移至 -7.4 V。此外，当 EG 为从 3.05 变为 3.2 eV，Ioff 的平均值从 3.13 × 10−13 变为 2.4 × 10−14 A。这意味着 EG 和 me 影响 a-IGZO TFT 中 Ioff 的增加，因为与 TAT 相关的困难.