Fabrication and characterization of high-quality and stable thin film using organic alloy method, and application of the film to organic devices

采用共蒸发法制备了有机合金薄膜。本文讨论了有机发光二极管中使用的空穴传输材料和空穴阻塞材料。在空穴输运材料中，我们制备了由三苯基二胺衍生物（TPD）和萘取代二胺衍生物（NPD）组成的有机合金薄膜。我们澄清了有机合金薄膜中的多晶化与两种单一薄膜相比明显受到抑制。在空穴阻断材料方面，我们将空穴传输材料的NPD、电子传输材料的恶二唑衍生物（PBD）、空穴阻断材料的非取代BCP （Bphen）和电子注入材料的锂喹啉（Liq）结合制备了基于bathocuproin （BCP）的合金薄膜。BCP薄膜具有不稳定的薄膜形态，在蒸发几个小时后立即结晶。然而，我们通过有机合金方法获得了稳定和高质量的bcp基合金薄膜。但由于BCP与Liq的尺寸匹配度较差，制备BCP有机合金薄膜一直未能成功。下一步，我们通过引入有机合金薄膜，以铝喹啉（A1q3）为发射材料制备oled。这些有有机合金薄膜的OLED显示出与没有有机合金薄膜的传统OLED相似的器件性能。即有机合金方法对oled的载流子输运影响较小。然而，在空穴堵塞层中，有机合金膜与密切相关的Bphen和PBD结合，虽然表现出稳定的膜结构和优异的电子性能，但与空穴传输材料NPD结合的有机合金膜表现出稳定的膜结构，但空穴堵塞性能较低。因此，NPD不能作为BCP的对抗分子。

We fabricated organic alloy films by a co-evaporation method. In this study, we discussed hole-transport materials and hole-blocking materials which are used in organic light-emitting diodes. In the case of hole-transport material, we fabricated organic alloy films consisting of a triphenyl diamine derivative (TPD) and naphthyl-substituted diamine derivative (NPD). We clarified that the polycrystallization in organic alloy films is remarkably suppressed as compared with both single films. In the case of hole-blocking material, we fabricated bathocuproin (BCP) -based alloy films combined with NPD of hole-transport material, oxadiazole derivative(PBD)of electron-transport material, non-substituted BCP (Bphen) of hole-blocking material and lithium quinoline(Liq)of electron-injection material. BCP thin films have a unstable film morphology and immediately crystallize after a few hours from evaporation. However, we obtained stable and high-quality BCP-based alloy films by the organic alloy method. But it was not successful to fabricate organic alloy film consisting of BCP and because the size matching between BCP and Liq is poor. As the next step, we fabricated OLEDs with aluminum quinoline (A1q3) as an emitting material by the introduction of organic alloy films. These OLEDs with an organic alloy film showed the similar device performance as the conventional OLED without an organic alloy film. That is, organic alloy method was found little to affect carrier transport of OLEDs. In the case of hole-blocking layer, however, although the organic alloy films combined with closely-related Bphen and PBD showed a stable film structure and an excellent electronic property, the organic alloy films combined with NPD of hole-transport material showed a stable film structure but a low hole-blocking property. Therefore, NPD could not be used as the counter molecule against BCP.