High Annealing Stability of InAlZnO Nanofiber Field-Effect Transistors with Improved Morphology by Al Doping

In 2 O 3 nanofibers usually suffer a high off-current and consequent low on/off current ratio, as well as a large negative threshold voltage ( V th ). Furthermore, regarding Zn doped binary-cation In 2 O 3 nanofibers, severe thermal diffusion of Zn elements can result in deteriorated electrical performance when annealed at high temperature. Here, we applied an electrospinning technique to obtain ternary-cation IAZO nanofibers with controllable V th and chemical stoichiometry. The presence of the Al element in IAZO nanofibers can lead to more superior microstructure with improved uniformity, lower surface defect, and superior metal–oxide–metal lattice at high annealing temperature. Consequently, our Al-doped ternary-cation IAZO devices exhibited an improved on/off current ratio of 10 7 and a high electron mobility of ∼10 cm 2 V –1 s –1 . Moreover, the electron mobility can be increased to 30 cm 2 V –1 s –1 in our low-voltage operated FETs with high- k AlO x as the dielectric layer, which can be envisioned to exhibit vast implications for high-performance transparent electronics.