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Fabrication of Scattering Layer for Light Extraction Efficiency of OLEDs  

Bae, Eun Jeong (Nano and Organic-Electronics Laboratory, Department of Display and Semiconductor Engineering, Sunmoon University)
Jang, Eun Bi (Nano and Organic-Electronics Laboratory, Department of Display and Semiconductor Engineering, Sunmoon University)
Choi, Geun Su (Nano and Organic-Electronics Laboratory, Department of Display and Semiconductor Engineering, Sunmoon University)
Seo, Ga Eun (Nano and Organic-Electronics Laboratory, Department of Display and Semiconductor Engineering, Sunmoon University)
Jang, Seung Mi (Nano and Organic-Electronics Laboratory, Department of Display and Semiconductor Engineering, Sunmoon University)
Park, Young Wook (Nano and Organic-Electronics Laboratory, Department of Display and Semiconductor Engineering, Sunmoon University)
Publication Information
Journal of the Semiconductor & Display Technology / v.21, no.1, 2022 , pp. 95-102 More about this Journal
Abstract
Since the organic light-emitting diodes (OLEDs) have been widely investigated as next-generation displays, it has been successfully commercialized as a flexible and rollable display. However, there is still wide room and demand to improve the device characteristics such as power efficiency and lifetime. To solve this issue, there has been a wide research effort, and among them, the internal and the external light extraction techniques have been attracted in this research field by its fascinating characteristic of material independence. In this study, a micro-nano composite structured external light extraction layer was demonstrated. A reactive ion etching (RIE) process was performed on the surfaces of hexagonally packed hemisphere micro-lens array (MLA) and randomly distributed sphere diffusing films to form micro-nano composite structures. Random nanostructures of different sizes were fabricated by controlling the processing time of the O2 / CHF3 plasma. The fabricated device using a micro-nano composite external light extraction layer showed 1.38X improved external quantum efficiency compared to the reference device. The results prove that the external light extraction efficiency is improved by applying the micro-nano composite structure on conventional MLA fabricated through a simple process.
Keywords
OLEDs; micro-nano structure; RIE; light extraction;
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