The degradation mechanism of amorphous InGaZnO (a-IGZO) thin-film transistors (TFTs) under pulse drain bias stress is investigated. Although the degradation mechanism is found to be a dc one, the shift of the transfer curve under the pulse drain bias (0-20 V) is unexpectedly larger than that under dc drain bias (20 V) within the same equivalent stress time. The degradation mechanism is proposed to be tunneling and trapping of electrons in the etching stop layer during the pulse peak time and that in the gate dielectric during the pulse base time under the extended drain electrode region of the a-IGZO TFT, where the occurrence of the latter is triggered by the former. A solution for enhancing the stability of the a-IGZO TFT is also suggested.

中文翻译：

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脉冲漏极偏置应力下 a-InGaZnO 薄膜晶体管的热载流子效应


研究了脉冲漏极偏置应力下非晶 InGaZnO (a-IGZO) 薄膜晶体管 (TFT) 的退化机制。尽管发现退化机制是直流机制，但在相同的等效应力时间内，脉冲漏极偏压 (0-20 V) 下的传输曲线偏移意外地大于直流漏极偏压 (20 V) 下的传输曲线偏移。退化机制被认为是在 a-IGZO TFT 的扩展漏极区域下，脉冲峰值时间期间蚀刻停止层中的电子以及脉冲基值时间期间栅极电介质中的电子的隧道和俘获，其中发生后者是由前者引发的。还提出了增强a-IGZO TFT稳定性的解决方案。