High-Performance Poly-Silicon TFTs Using a High- $k$ $\hbox {PrTiO}_{3}$ Gate Dielectric

In this letter, a polycrystalline-silicon thin-film transistor (poly-Si TFT) with a high-k PrTiO₃ gate dielectric is proposed for the first time. Compared to TFTs with a Pr₂O₃ gate dielectric, the electrical characteristics of poly-Si TFTs with a PrTiO₃ gate dielectric can be significantly improved, such as lower threshold voltage, smaller subthreshold swing, higher I _on/I _off current ratio, and larger field-effect mobility, even without any hydrogenation treatment. These improvements can be attributed to the high gate capacitance density and low grain-boundary trap state. All of these results suggest that the poly-Si TFT with a high-k PrTiO₃ gate dielectric is a good candidate for high-speed and low-power display driving circuit applications in flat-panel displays.