By melting tetraphenylethene (TPE) and 1,2,4,5-tetraphenyl-1H-imidazole (TPI) units together through different linking positions, three new fluorophores are synthesized, and their optical, electronic and electroluminescence (EL) properties are fully studied. Owing to the presence of TPE unit(s), these fluorophores are weak emitters in solutions, but are induced to emit strongly in the aggregated state, presenting typical aggregation-induced emission characteristics. The experimental and computational results reveal that different connection patterns between TPE and TPI could impact the molecular conjugation greatly, leading to varied emission wavelength, fluorescence quantum yield and EL performance in organic light emitting diodes (OLEDs). The fluorophore built by attaching TPE unit to the 1-position of imidazole ring shows bluest fluorescence, and its EL device emits at deep blue region (445 nm; CIE = (0.16, 0.15)). And the device based on the fluorophore by linking TPE to the 2- position of imidazole ring shows EL at 467 nm (CIE = (0.17, 0.22)) with good efficiencies of 3.17 cd·A–1, and 1.77%.

以衬底温度和射频(RF)功率为调控晶化多晶硅薄膜的氢等离子钝化处理工艺的参数,借助发射光谱(OES)全程实时探测以及对氢化处理后薄膜的傅里叶变换红外吸收谱(FTIR)的分析,通过钝化前后薄膜电性能相对照,探讨工艺优化的微观机理。对于LPCVD为晶化前驱物SPC晶化的样品,氢等离子体中的Hβ和Hγ基元对氢钝化处理起主要作用。硅薄膜氢化处理后膜中的氢以Si-H或Si-H2的形态大量增加。随氢化处理的温度升高,促使Hβ和Hγ以更高的动能在表面移动并进入薄膜内与硅悬挂键键合。只有提供足够的动能才能有效改善多晶硅微结构(R降低),使霍尔迁移率得以增大;样品在足够高的衬底温度下,只需较低功率即能产生所需数量的Hβ和Hγ等离子基元对样品予以钝化。降低功率,能有效降低I2100、继而减小R,从而减少对薄膜的轰击和刻蚀,有利提高电学性能。实验中样品氢化处理较优化的条件为550 ℃,10 W,其霍尔迁移率提高了43.5%。

开发了一种新的双向取向表面。所述取向表面可以用于控制液晶引流(backflow)方向。基于所述新型取向层,成功制造了一种双稳态扭曲向列相LCD,该LCD在U和T态之间转换,不伴随表面锚泊能的破坏(surface anchoring energy breaking)。