Hole-confining Concept for Blue Organic Light Emitting Diode

Download or read book Hole-confining Concept for Blue Organic Light Emitting Diode written by Balasaheb S. Darade and published by . This book was released on 2011 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: Organic Light Emitting Diodes (OLEDs) have received wide attention in recent yearsbecause of their advantages of light-weight, wide viewing angle, self-emission and promise oflow cost. There is continuous increase in demand for OLEDs applications particularly in solidstate lighting and color displays. With such huge potential there is also an urgent need for moreresearch in improving efficiency and lifetime. Blue OLEDs are the bottleneck in both of theseimportant performance parameters among three primary colors (green, red and blue). The main objective of this thesis was to implement blue OLEDs and improve theirefficiencies and lifetimes by using a novel 'hole-confining' structure. Generally, in organicsemiconductors, the hole mobility is higher than electron mobility by few orders of magnitude. This mismatch of electron and hole mobilities is detrimental because it leads to a lowerrecombination rate and leads to a degradation in device performance. In this thesis, we used theconcept of a 'hole confining' structure to overcome this challenge. This helps enhancing therecombination rate and the overall device performance. In chapter 2, a step by step description of the various OLED fabrication procedures ispresented. Also different OLED devices made in the Spintronics and Nanoelectronics lab at theUniversity of Cincinnati so far are discussed. In chapter 3, we implemented a blue OLED with aITO/TPD/BCP/LiF/Al structure first, and then improved the OLED performance, by using aITO/PEDOT:PSS/TPD/BCP/Alq3/LiF/Al structure resulting in a brighter blue OLED. This workwas the first successful fabrication and characterization of blue OLEDs in Dr. Cahay's lab. Finally, a comparison of all devices fabricated is presented, and suggestions for future work areoffered.