Investigation of top-emitting OLEDs using molybdenum oxide as anode buffer layer

Abstract

A high-effective bottom anode is essential for high-performance top-emitting organic light-emitting devices (OLEDs). In this paper, Ag-based top-emitting OLEDs are investigated. Ag has the highest reflectivity for visible light among all metals, yet its hole-injection properties are not ideal for anodes of top-emitting OLED. The performance of the devices is significantly improved using the molybdenum oxide as anode buffer layer at the surface of Ag. By introducing the molybdenum oxide, the hole injection from Ag anodes into top-emitting OLED is largely enhanced with rather high reflectivity retained.

Keywords

Hole Injection / Apply Physic Letter / Molybdenum Oxide / Bottom Anode / Anode Buffer Layer

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This work has been supported by the National Natural Science Foundation of China (No.60425101), the Young Excellence Project of University of Electronic Science and Technology of China (No.UESTC-060206), and the Fundamental Research Funds for the Central Universities of China (Nos. ZYGX2010Z004 and ZYGX2009J054).