Effects of Substrate Temperature on the Physical Properties of ITO/NPB/Alq3/Al Heterostructures

基板溫度對ITO/NPB/Alq3/Al異質結構之物性的影響

湯秀靜(Shiow-Jing Tang)；蘇志豐(Chih-Feng Su)；林谷彥(Ku-Yen Lin)；王智祥(Jyh-Shyang Wang)；邱寬城(Kuan-Cheng Chiu)

有機發光二極體 ； 物性量測 ； 基板溫度效應 ； 熱蒸鍍法 ； organic light-emitting diodes ； physical characterization ； effect of substrate temperature ； thermal evaporation chamber

先進工程學刊

8卷4期（2013 / 10 / 01）

191 - 195

英文

本論文利用不同的基板溫度（Tsub）於壓力約10^(-7) Torr之熱蒸鍍腔體中製作具有ITO/NPB/Alq3/Al基本架構之有機發光二極體（OLED）。由原子力顯微鏡、X光繞射、電流密度與外加偏壓、和發光強度與外加偏壓的特性分析，本文探討所成長之有機分子薄膜及其所製作之OLED元件的表面形貌、結構性質、電性與發光特性。當Tsub由30℃增加到90℃，黏著於成長中之介面的有機小分子（NPB或Alq3）可獲得較高之表面擴散動能，並導致所成長之有機薄膜具有較平坦的形貌與較緻密的結構。因此，在Tsub = 90℃下所製作之OLED具有較高之電致螢光發光效率。

In this paper, organic light-emitting diodes (OLEDs) with a basic structure of indium tin oxide (ITO)/naphthyl-substituted benzidine derivative (NPB)/tris-8-(hydroxyquinoline) aluminum (Alq3)/Al were fabricated in a thermal evaporation chamber at various substrate temperatures (Tsub) under pressure around 10^(-7) Torr. Through atomic force microscopy, x-ray diffraction, current density-voltage and luminescence intensity-voltage analysis, a study on surface morphology, structural information, electrical and optical properties of the as-deposited organic layers as well as the as-fabricated OLEDs was performed. With increasing Tsub from 30℃ to 90℃, the adhering organic molecules on the growing interface gain more surface diffusion energy, and the as-deposited organic layers possess flatter surface morphology and more compact structure. Accordingly, higher values of electroluminescence efficiency were obtained from OLEDs fabricated at Tsub = 90℃.