Investigation of organic light-emitting devices using resonant cavity structure and lasing properties of organic emitters with aggregation induced emission characteristics

• Main Authors: Kai-Wen Chang, 張凱文
• Other Authors: Li-Yin Chen
• Format: Others
• Language: zh-TW
• Published: 2014
• Online Access: http://ndltd.ncl.edu.tw/handle/ynn8d4

碩士 === 國立中山大學 === 光電工程學系研究所 === 102 === The first part of this thesis is concentrated on the color purity performance improvement of blue phosphorescent OLEDs. We integrated a high efficiency blue OLEDs with conducting DBR anodes, then optimized this device by modulating the thickness of organic films. With this configuration, we successfully improved the color purity of the blue-emitting device. The CIE 1931 color coordinate of the blue-emitting device with cavity structure was located at (x,y)= (0.14,0.14), and it of the device with no cavity structure was located at (x,y)=(0.14,0.35). In the second part of this thesis, we investigated two materials with aggregation induced emission (AIE) properties named as TPATPE and 2TPATPE. Due to their high steric hindrance, they can be well utilized in high efficiency OLEDs. First, we set the amplified spontaneous emission (ASE) experiments to measure their ASE thresholds, ASE spectrum, gain coefficients and loss coefficients. The results revealed that both TPATPE and 2TPATPE have good optical amplification properties with ASE thresholds about 2.7kW/cm2 and 4.9kW/cm2 and gain coefficients are 19cm -1 and 23cm-1, respectively. With a suitable resonant condition realized by 1-D DFB structure and the high gain materials, spectral narrowing and optical amplification properties were observed. Finally, two double-layered florescent OLEDs with high efficiencies were demonstrated. The EQE of TPATPE and 2TPATPE devices were 4.3% and 4.6%, respectively. This results indicated that both of these two materials are well suitable for display or lighting applications.