Characteristics of double-gate a-IGZO TFT

摘要

A double-gate (DG) a-IGZO TFT with separate bottom-gate and top-gate is fabricated and electrically characterized. It is shown that the double-gate device has a steeper sub-threshold swing, a larger carrier mobility, and a driving current 2.4 times larger than the conventional single-gate device. Due to the lowered vertical electric field across the channel region, a negligible V shift is observed for the double-gate device under negative gate bias stress. Moreover, the dynamic threshold voltage effect has also been demonstrated due to the separate two gates in the TFT.