Characteristics of Gate-All-Around Twin Poly-Si Nanowire Thin-Film Transistors

We have investigated the characteristics of gate-all-around (GAA) twin polycrystalline-silicon nanowire (NW) thin-film transistors (TFTs). The NW channel and surrounding gate imparted the GAA twin NW TFT with superior channel controllability. Moreover, the combination of the high surface-to-volume ratio of the NW and the split channel structure led to highly efficient NH₃ plasma treatment, which reduced the effective grain-boundary trap-state density. The GAA twin NW TFT exhibited greatly improved electrical performance, including a lower threshold voltage, a steeper subthreshold swing (114 mV/dec), a higher on/off current ratio (> 10⁸), and a virtual absence of drain-induced barrier lowering (13 mV/V).