Study of sol gel-deposited ZnO external light extraction thin films to enhance the efficiency in organic light-emitting diodes

• Main Authors: Yu-Chi Su, 蘇昱齊
• Other Authors: Mei-Ying Chang
• Format: Others
• Language: zh-TW
• Published: 2018
• Online Access: http://ndltd.ncl.edu.tw/handle/zhuytm

碩士 === 國立中山大學 === 光電工程學系研究所 === 106 === In this study, we fabricated organic light-emitting diodes (OLEDs) with external light extraction structure to reduce the Substrate mode loss and increase the EQE by using the Sol–gel-deposited zinc oxide (ZnO) micro structure thin films. And we successfully applied the external light extraction to the organic light-emitting diodes. First, we use the spin-coating to fabricate the ZnO thin film for forming various thickness by using different spin rate. We investigated surface morphology and transmittance of the ZnO thin film. Then, we anneal different temperature and also different ways to raise the annealing temperature. We investigated surface morphology and optical characteristics of the ZnO thin film, and we improve the ZnO thin film to match the condition of external light extraction structure. Finally, we successfully fabricated blue OLEDs with the Sol–gel-deposited ZnO light extraction thin films. Significantly, the blue OLEDs with external light extraction structure have great light extraction efficiency which increase the external quantum efficiency (EQE) by 43% compared to standard OLEDs at 1000cd/m2.