Extremely Stable Dual Gate Coplanar Amorphous InGaZnO Thin Film Transistor With Split Active Layer by N2O Annealing.

We report the effect of N2O post-fabrication annealing (PFA) on the electrical stability of dual gate, active split amorphous indium gallium zinc oxide (a-IGZO) thin-film transistor (TFT). Optimized N2O PFA at 360 °C for 3 h results in threshold voltage (VTH) close to zero and an increase in the on-current almost 2 times than as-fabricated TFT. N2O annealed TFT exhibited robust VTH stability under positive bias temperature stress at 60 °C and negative bias illumination stress, exhibiting $\Delta \text{V}_{\text {TH}}$ of 0.1 V, and- 0.1 V, respectively, whereas as-fabricated TFT showed large $\Delta \text{V}_{\text {TH}}$ of ~ 10 V and −3 V. The X-ray photoelectron spectroscopy depth profile reveals the origin of such improvement as the increasing metal-oxide bonds and the reduction in oxygen vacancy / OH related defects. [ABSTRACT FROM AUTHOR]