Use of Hole and Electron Impeding Layers to Improve the Efficiency of Organic Light Emitting Diodes

Download or read book Use of Hole and Electron Impeding Layers to Improve the Efficiency of Organic Light Emitting Diodes written by Nikhil K. Bhandari and published by . This book was released on 2009 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: The last two decades have seen and increased interest in the development of Organic Light Emitting Devices (OLEDs) as well as interest in realizing products employing the OLED technology because of the inherent advantage and extremely low power consumption this technology offers over its counterparts. The spiralling cost and demand for energy has once again brought to fore energy efficient technologies like OLED. In this thesis, we have used charge impeding layer to enhance the performance of our OLEDs. It is a well know fact that hole mobility is about two orders of magnitude higher then electron mobility in organic materials and this results in unbalanced charges as well as hole leakage problems in OLEDs especially at lower current densities. The other problem that we address in this thesis is the formation of "hole trap" in case of doped OLEDs. We propose two device structures, a Hole impeding Layer (HiL) structure for undoped OLEDs and an electron impeding structure in case of doped OLEDs. We analyze the performance improvement observed by employing these device structures.