有機半導體發光元件之有機與金屬界面動態特性研究

The Study of Dynamical Characteristics of Organic/Metal Interfaces in Organic Semiconductor or Light-Emitting Devices

蔡志瑋(Chih-Wei Tsai)

指導教授 ： 楊恆隆

國立臺北科技大學/電資學院/光電工程系研究所/碩士(2007年)

摘要

利用光散射法之表面電漿共振(Surface plasmons resonance)非破壞性技術來探討有機半導體發光元件之有機層與金屬層界面的動態特性。有機材料與金屬電極界面的動態特性意即元件處於操作狀態時此界面因載子注入而產生之變化反應。此變化狀態藉由分析有機與金屬動態界面之表面電漿共振反射角頻譜的變化趨勢獲得。研究結果發現紅光元件在入射光波長632.8nm量測下均呈現元件反射率隨外加電壓上升而下降，而在685nm時多數元件反射率不隨電壓改變。綠光元件在波長632.8nm及685nm均呈現反射率隨外加電壓上升而下降。藍光元件在632.8nm多數元件反射率隨外加電壓增大而下降，685nm則多數元件反射率不隨電壓改變。白光元件在632.8nm均呈現元件反射率隨外加電壓上升而下降，在685nm元件反射率隨外加電壓上升而下降及元件反射率不隨電壓改變的情形各半。就兩種入射光波長來看，波長632.8nm比685nm對有機材料的吸收較強，685nm對有機材料較近似於透明，代表著有機材料在波長632.8nm比685nm的吸收係數較高，薄膜行為較為明顯。

關鍵字

有機半導體元件 ； 有機與金屬界面 ； 光散射 ； 表面電漿共振

並列摘要

This thesis research is to study the dynamical characteristics of organic/metal interface in organic light-emitting devices (OLED) or organic semiconductors by means of non-destructive optical reflectivity measurement. The phenomena of surface plasmons resonance (SPR) may also be observed in reflectivity spectra. This research is mainly focused on in-situ probing the organic/metal interface as carrier injection occurs during device operation. The dynamical characteristics of organic/metal interface indicate that the phenomena of interfacial variation and carrier injection may occur simultaneously during device operation. These interfacial characteristics may be in sensitive response to the reflectivity spectra in conjunction with SPR. Our experimental results showed that the reflectivity spectra decrease as applied voltages increase in 632.8 nm incident wavelength for all red devices. But there’s no obvious variation in reflectivity spectra in 685 nm incident wavelength. The reflectivity spectra for green devices showed decreasing tendency in both 632.8 nm and 685 nm incident wavelengths as applied voltages increase. The reflectivity spectra for most blue devices showed similar trend of red devices in 632.8 nm incident wavelength. The reflectivity spectra for white devices also showed similar trend of red devices in 632.8 nm incident wavelength. Some of the white devices showed similar reflectivity spectra with green devices in 685 nm incident wavelength. The absorption property of organic materials in 632.8 nm wavelength is stronger than that in 685 nm wavelength. It’s expected that the interfacial reactions in 632.8 nm is stronger than that in 685 nm wavelength.

並列關鍵字

Organic semiconductor Device ； Organic/Metal interface ； Light Scattering ； Surface Plasmons Resonance

參考文獻

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