Competition between heating and cooling during dynamic self-heating degradation of amorphous InGaZnO thin-film transistors

作者：Zhou, Yuheng; Liu, Fayang; Yang, Huan; Zhou, Xiaoliang; Li, Guijun; Zhang, Meng; Chen, Rongsheng; Zhang, Shengdong^*; Lu, Lei^*

来源：Solid-State Electronics, 2022, 195: 108393.

DOI：10.1016/j.sse.2022.108393

• a-IGZO
• Thin-film transistors
• High current stress
• Self-heating
• Dynamic stress

The dynamic self-heating (SH) instability of a-InGaZnO (a-IGZO) thin-film transistors (TFTs) was systematically investigated under static drain bias and pulsed gate voltage. The a-IGZO TFTs exhibited three distinct degradation stages, including a slightly positive shift of threshold voltage (& UDelta;Vth), then a gradually negative & UDelta;Vth, and finally an accelerated negative shift leading to normally-on characteristics. The underlying mechanisms were clarified to be SH-enhanced positive bias stress (PBS) instability, SH-generated donor defects, and the donor populated central channel, respectively. By changing the duty ratio, frequency, peak, and base periods of gate pulses. The competition between heating and cooling periods was found to dominate the behavior and degree of dynamic SH degradations, suggesting a feasible instability-relieving method by sophisticatedly adjusting the dynamic operating conditions.

• 单位
  北京大学