We have fabricated poly(3-hexylthiophene) organic field-effect transistors (P3HT-OFETs) with either high-temperature (200 C) thermally cured PVP gate dielectrics or low-temperature (120 C) photocured PVP gate dielectrics. We prepared the thermally cured PVP dielectric layer from a blend of poly(4-vinylphenol) (PVP) and poly(melamine-co-formaldehyde) (PMF); the photo-cured PVP dielectric formulation contained an additional photo-acid generator (PAG), which allowed the temperature for the cross-linking reaction to be reduced. We examined the intrinsic dielectric properties (e.g., the dielectric constant, the electrical insulating properties) and surface properties (e.g., morphology, surface energy) of the formulations loaded with various amounts of PAG (from 0 to 2.4 wt%). The P3HT-OFETs with the thermally cured PVP gate dielectrics exhibited an excellent carrier mobility of ca. 0.1 cm 2 V À1 s À1 , a sub-threshold swing of 2.0 V decade À1 , and an on/off ratio of 1.2 Â 10 4 . For comparison, the P3HT-OFET devices with the photo-cured PVP gate dielectrics also exhibited good electrical characteristics, including carrier mobilities as high as 0.06 cm 2 V À1 s À1 , sub-threshold swings as low as 1.4 V decade À1 , and on/off ratios as large as 3.0 Â 10 4 . To take advantage of the photocured PVP films, we also fabricated OFETs on a flexible, cheap ITO/PET substrate.

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Typhoon Morakot hit southern Taiwan in 2009, bringing 48-hr of heavy rainfall [close to the Probable Maximum Precipitation (PMP)] to the Tsengwen Reservoir catchment. This extreme rainfall event resulted from the combined (co-movement) effect of two climate systems (i.e., typhoon and southwesterly air flow). Based on the traditional PMP estimation method (i.e., the storm transposition method, STM), two PMP estimation approaches, i.e., Amplification Index (AI) and Independent System (IS) approaches, which consider the combined effect are proposed in this work. The AI approach assumes that the southwesterly air flow precipitation in a typhoon event could reach its maximum value. The IS approach assumes that the typhoon and southwesterly air flow are independent weather systems. Based on these assumptions, calculation procedures for the two approaches were constructed for a case study on the Tsengwen Reservoir catchment. The results show that the PMP estimates for 6-to 60-hr durations using the two approaches are approximately 30% larger than the PMP estimates using the traditional STM without considering the combined effect. This work is a pioneer PMP estimation method that considers the combined effect of a typhoon and southwesterly air flow. Further studies on this issue are essential and encouraged.

This work studies the NH 3 plasma passivation on a novel gate-allaround poly-Si TFTs with multiple nanowire channels (GAA-MNC TFTs). The NH 3 plasma passivation can effectively passivate the defects in poly-Si channel and improve the electrical performance of poly-Si TFTs. As comparison to conventional TFTs, the GAA-MNC TFTs with NH 3 plasma passivation exhibit outstanding three-dimensional gate controllability and excellent electrical characteristics, which revealed a high ON/OFF current ratio (>10 8 ), a low threshold voltage, a steep subthreshold swing, and a near-free drain-induced barrier lowering. Therefore, such the high-performance GAA-MNC TFTs are very suitable for the applications in the system-on-panel (SOP) and three-dimensional (3D) circuits.