氟代金属酞菁半导体材料的合成、性能与薄膜器件研究

During the past two decades, there has been great interest in organic semiconductors due to their potential application in sensors, display and logic circuit. Compared with traditional silicon electronics, the electronic based on organic semiconductors offers many advantages, such as mechanical flexibility, light weight and low cost, and has been considered as the next generation of principle semiconductor devices. It is a great challenge to develop novel organic semiconducting materials with high mobility and air stability, especially for the n-type materials. This project will focus on the synthesis and application of fluorinated metal-phthalocyanines as n-type organic semiconducting materials. A series of fluoro-substituted symmetrical and unsymmetrical metal-phthalocyanines of "electronics-grade" purity will be synthesized and characterized. The obtained fluorinated metal-phthalocyanines are thereafter employed as the active layer in the organic thin film transistor (OTFT) and the transient behavior of the OTFT will be evaluated. The organic film is prepared by vapor deposition technique and the operation parameters are optimized to improve the film morphology. In addition, the charge transporting properties of the fluorinated metal-phthalocyanines will be theoretically investigated by evaluating the dimer Fock matrix. The dependence of charge transfer integrals on the material structure and intermolecular packing style will be studied in detail.

近二十年来，有机半导体器件由于其在大面积、低成本和柔性化电子产品方面的潜在应用前景而在世界范围内引起广泛关注，被认为是下一代的主流半导体器件。有机半导体材料的合成及其应用是目前的研究热点，尤其是高效稳定的n型有机半导体材料的设计开发及其电荷传输机理研究。本项目旨在：合成出一系列半导体纯度的氟代金属酞菁类n型半导体材料,对其合成工艺和提纯条件进行优化；制备均匀致密的氟代金属酞菁薄膜，研究影响薄膜表面形貌的关键因素；以氟代金属酞菁作为有源层制备薄膜晶体管，测试其性能参数，筛选出具有高迁移率的在空气中稳定的n型有机半导体材料。最后，建立理论模型，通过量子化学计算，揭示材料分子结构与电子性质的关系，研究其电荷传输机制，以期为高效有机半导体材料的研发提供实验及理论依据。

近二十年来，有机半导体器件由于其在大面积、低成本和柔性化电子产品方面的潜在应用前景而在世界范围内引起广泛关注，被认为是下一代的主流半导体器件。有机半导体材料的合成及其应用是目前的研究热点，尤其是高效稳定的n型有机半导体材料的设计开发及其电荷传输机理研究。本项目合成了一系列半导体纯度的氟代金属酞菁类半导体材料（FxMPc），对其合成工艺和提纯条件进行了优化。采用真空热沉积的方法制备氟代金属酞菁薄膜，研究了基板温度、基底诱导层修饰对薄膜形貌和分子堆积方式的影响，获得了制备均匀致密薄膜的最优条件。采用四氟取代酞菁铜、八氟取代酞菁铜、十二氟取代酞菁铜和十六氟取代酞菁铜（FxCuPc, x=4, 8, 12, 16）作为有源层材料制备了薄膜场效应器件。利用量子化学计算、X射线衍射（XRD）和原子力显微镜（AFM）系统研究了氟原子数目对分子结构、分子轨道能级、薄膜形貌和微观结构、分子堆积方式及材料半导体性能等方面的影响。制备了有机薄膜场效应器件研究FxCuPc的半导体特性和电荷传输性能。十六氟取代酞菁铜（F16CuPc）器件的电子迁移率为0.27 cm2V-1s-1。十二氟酞菁铜（F12CuPc）场效应器件在空气环境中表现出双极性特性，其空穴迁移率和电子迁移率分别为0.005 cm2V-1s-1和0.006 cm2V-1s-1。实现了通过引入强吸电子取代基有效调控金属酞菁轨道能级，进而制备单一组分的p型、双极性和n型有机薄膜场效应器件。基于F16CuPc的薄膜场效应器件在空气中具有较好的稳定性。同时基于量子化学的方法计算了材料的重组能和转移积分评估材料的电荷传输性能，为高效有机半导体材料的开发提供实验及理论依据。