红荧烯多晶薄膜的形态结构研究

Rubrene holds the record for the highest carrier mobility of organic semiconductor materials. However, it has been found difficult to achieve high carrier mobility in thin film transistors of rubrene because of poor crystallinity. Rubrene films prepared by conventional vacuum deposition method on the amorphous substrate, generally shows the amorphous state.The carrier mobility in amorphous films is very low (10-6 cm2/Vs),does not show high functional characteristics of rubrene crystalline material, limits the practical application of the materials in thin film devices greatly. Weak epitaxial growth (WEG) is an effective method for the preparation of high ordered organic semiconductor thin film. At first, a layer of high ordered ultra-thin films of organic molecules inducing layer is prepared in an amorphous substrate, and then the polycrystalline thin film of organic semiconductor grow on the surface of the inducing layer. There is formed some epitaxial relationship between organic semiconductor crystal and inducing layer. The project is planned to fabricate the high-quality rubrene polycrystalline films on amorphous substrates by WEG method and carry out researching the relationship between morphology and function of the rubrene weak epitaxial growth film systematically.

红荧烯(Rubrene)是目前报道的载流子迁移率最高的一类有机半导体材料，然而，由于薄膜结晶性差导致红荧烯薄膜晶体管难以获得高迁移率。采用常规的真空沉积方法 在非晶衬底上制备的红荧烯薄膜，一般呈现非晶状态，载流子迁移率非常低(10-6 cm2/Vs)，没有表现出该材料结晶态时具有的高功能性质，大大限制了该材料在薄膜器件方面的实际应用。弱外延生长（WEG）是制备高有序有机半导体薄膜的一种有效方法，是在非晶衬底上先制备一层高有序的有机分子超薄膜诱导层，然后再生长有机半导体多晶薄膜，有机半导体晶体与诱导层之间会形成一定的外延关系。本项目拟通过WEG方法在非晶衬底上实现高品质红荧烯多晶薄膜的制备，并系统开展红荧烯弱外延生长薄膜的形态结构与功能关系研究。

红荧烯(Rubrene)是目前报道的载流子迁移率最高的一类有机半导体材料，然而，由于薄膜结晶性差导致红荧烯薄膜晶体管难以获得高迁移率。弱外延生长（WEG）是制备高有序有机半导体薄膜的一种有效方法，是在非晶衬底上先制备一层高有序的有机分子超薄膜诱导层，然后再生长有机半导体多晶薄膜，有机半导体晶体与诱导层之间会形成一定的外延关系。本项目通过WEG方法在非晶衬底上实现了高品质红荧烯多晶薄膜的制备，并系统开展了红荧烯弱外延生长薄膜的形态结构与功能关系研究。在间七联苯诱导层单层薄膜上制备出了高有序、单取向的红荧烯结晶薄膜。以此为基础制备的红荧烯薄膜晶体管的器件性能最优迁移率达到8.8cm2/Vs。引入VOPc 为缓冲层后，晶体管器件性能进一步提高其迁移率达到11 cm2/Vs 以上。开展了对于高有序红荧烯结晶薄膜成核规律以及特性的研究，为制备高质量的红荧烯结晶薄膜提供了一定的理论基础。