Effects of Filtration Process and Thermal Treatment on Optoelectronic Characteristics of MEH-PPV Polymer Light-Emitting Diodes

• Main Authors: Yi-Chung Liang, 梁義忠
• Other Authors: Jyh-Wong Hong
• Format: Others
• Language: en_US
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/9s84ga

碩士 === 國立中央大學 === 電機工程研究所 === 94 === Abstract Since the thermal treatment (or annealing) is an important technique to control the morphology of poly(2-methoxy-5-(2’ethylhexoxy)-1, 4-phenylene-vinylene) (MEH-PPV) film, it has been employed in this study to improve the performances of MEH-PPV-based PLEDs fabricated on the glass or plastic substrate. The optimal thermal treatment condition could reduce the electroluminescence (EL) threshold voltage and enhance the brightness of a PLED. Also, the unfiltered powders of dissolved MEH-PPV played an important role affecting the device performance. They would confine the carriers and hence the recombination rate of electron-hole pairs could be enhanced. With the proper filtration process and thermal treatment condition, the device obtainable on glass substrate had a brightness (luminance efficiency) of 436,000 cd/m2 (130 cd/A) at an injection current density of 355 mA/cm2, and an EL threshold voltage of 6.4 V. Also, the device obtainable on plastic substrate had a brightness (luminance efficiency) of 43,600 cd/m2 (7.11 cd/A) at an injection current density of 600 mA/cm2, and an EL threshold voltage of 8.5 V.