For the first time, the mobility enhancement mechanism due to the SiO2 passivation layer (PVL) in amorphous InGaZnO (a-IGZO) thin-film transistors (TFTs) is studied using technology-computer-aided design (TCAD) simulation. Our results indicate that the introduction of oxygen vacancies in shallow donor states around the PVL/a-IGZO interface, which donate more free electrons in the induced accumulation layer of the channel, increases the field-effect mobility of the TFT by $5.7\times {}$ . Results of our TCAD simulations are strongly supported by X-ray photoelectron spectroscopy (XPS) measurements. Furthermore, TCAD analysis of a three-stage ring oscillator composed of the sample with PVL indicates 27-MHz oscillation frequency is possible at 10-V supply voltage.

中文翻译：

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通过 SiO2 钝化层对非晶 InGaZnO 薄膜晶体管迁移率的物理洞察

首次使用技术计算机辅助设计 (TCAD) 模拟研究了由非晶 InGaZnO (a-IGZO) 薄膜晶体管 (TFT) 中的 SiO2 钝化层 (PVL) 引起的迁移率增强机制。我们的结果表明，在 PVL/a-IGZO 界面周围的浅施主态中引入氧空位，在通道的诱导积累层中提供更多的自由电子，使 TFT 的场效应迁移率增加了 $5.7\times { }$ 。我们的 TCAD 模拟结果得到 X 射线光电子能谱 (XPS) 测量的有力支持。此外，由具有 PVL 的样本组成的三级环形振荡器的 TCAD 分析表明，在 10V 电源电压下，27MHz 的振荡频率是可能的。