Roles of Hot Carriers in Dynamic Self-Heating Degradation of a-InGaZnO Thin-Film Transistors

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

来源：IEEE Electron Device Letters, 2022, 43(1): 40-43.

DOI：10.1109/LED.2021.3133011

• Amorphous oxide semiconductor (AOS)
• indium-gallium-zinc-oxide (IGZO)
• thin-film transistor (TFT)
• self-heating (SH)
• hot-carrier (HC)
• dynamic stress
• instability
• breakdown

The dynamic self-heating (SH) degradation was investigated on a-InGaZnO (a-IGZO) thin-film transistors (TFTs) under constant drain bias and varied gate pulses. Besides the negative shift of threshold voltage (V-th), similar with that under DC SH stress, the asymmetric degradations near drain and source revealed the concomitant hot-carrier (HC) effect. The HC-induced local barrier near drain could compensate certain SH-induced Vth shift, while a drastic SH effect would in turn enhance the HC barrier to high enough to cause hard breakdown. For a-IGZO TFTs under dynamic SH stresses, the interactions between SH and HC effects dominate the degradation behaviors and can be sensitively tuned by the falling time of gate pulse, suggesting a feasible method of lessening the dynamic instability.

• 单位
  北京大学