High-Performance Poly-Si TFTs With Pr2 O3 Gate Dielectric

In this letter, a polycrystalline silicon thin-film transistor (poly-Si TFT) with high-quality praseodymium oxide (Pr₂O₃) gate dielectric is proposed. Compared to TFTs with tetraethoxysilane gate dielectric, the electrical characteristics of poly-Si TFTs with Pr₂O₃ gate dielectric can be significantly improved, such as lower threshold voltage, lower subthreshold swing, triple ON/OFF current ratio, and a field-effect mobility that is about twice higher, even without any hydrogenation treatment. These improvements can be attributed to the high gate capacitance density by using a high-kappa gate dielectric. Therefore, the poly-Si TFT with Pr₂O₃ high-kappa gate dielectric is a promising candidate for high-speed and low-power display driving circuit applications in flat-panel displays.