Field-induced carrier generation in amorphous-InGaZnO4 thin-film transistors

作者：Um Jae Gwang; Mativenga Mallory; Migliorato Piero; Jang Jin^*

来源：Solid State Communications, 2014, 194: 54-58.

DOI：10.1016/j.ssc.2014.06.013

• Amorphous-indium-galium-zinc-oxide
• (a-IGZO)
• Thin-film transistor (TFT)
• Positive-bias-stress (PBS)
• Bias stability

The positive threshold voltage (V-TH) shift induced by positive gate bias stress (PBS) in amorphousindium-gallium-zinc-oxide (a-IGZO) thin-film transistors (TFTs) is commonly attributed to carrier trapping mechanism. Here we show that in addition to these trapping mechanisms, the concentration of donors also increases during PBS when the applied gate bias stress voltage V-Gs_(Stress) %26lt;= 30. In the early stages of the PBS, this increase in donor concentration may manifest itself as a negative V-TH shift. In the case of V-Gs_(Stress) %26gt;= 40 V, however, the increase is not detectable because electron trapping at the semiconductor/gate-insulator interface is dominant - even in the early stages of the PBS.

• 出版日期2014-9