以有機分子修飾電極表面對有機發光二極體元件效能影響研究

Self-assembled monolayers;Organic light-emitting diodes;Schottky barrier;Hole/electron carriers balance

余思燕(Szu-Yen Yu) ； 陶雨台(Yu-Tai Tao)

《化學》 67卷4期 (2009/12) Pp. 327-339

https://doi.org/10.6623/chem.2009032

摘要

利用自組裝單分子薄膜 (Self-assembled monolayers，SAMs) 修飾有機發光二極體的電極表面，可以有效地調控電極表面功函數，從而調控電極與有機層之間之蕭特基能障 (Schottky barrier)，以尋求注入電子電洞的平衡。本文舉例說明，針對不同的電極材料，都有相對應可使用的官能基分子，形成單分子薄膜。例如金屬銀或金電極，可使用硫醇分子吸附於表面；銦錫氧化物 (Indium-Tin oxide, ITO) 電極，則可使用三烷氧矽基分子或磷酸分子進行表面吸附。而針對電洞傳輸層的不同，也可藉由改變吸附分子的偶極距大小、吸附分子的長度，調控由陽極注入電洞的效率，以得到最佳的電子電洞再結合效率，提升元件發光效率。

關鍵字

自組裝單分子薄膜 ； 有機發光二極體 ； 蕭特基能障 ； 電子電洞載子平衡

並列摘要

Self-assembled monolayers were used to modify the electrode surfaces of organic light-emitting diodes in an effort to modify the electrode work function. The Schottky barriers at the metal/organc interface are thus fine-tuned to approach the electron/hole carriers balance in the device. Examples are shown to demonstrate that for different electrode surfaces, there are appropriate functional molecules used to form self-assembled monolayers. Thus organic mercaptans can be used for modify gold or silver surface, whereas trialkoxyalkylsilane or organophosphonic acids can be used to form monolayer on Indium-tin-oxide surface. For different hole-transport materials, the efficiency for hole injection can be controlled by using the molecular dipole or the molecular chain length. Optimized luminous efficiency can thus be approached for a specific device configuration.

並列關鍵字

Self-assembled monolayers ； Organic light-emitting diodes ； Schottky barrier ； Hole/electron carriers balance