New Organic Thin-Film Encapsulation for Organic Light Emitting Diodes

Rakhi Grover, Ritu Srivastava, Omwati Rana, D. S. Mehta, M. N. Kamalasanan

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DOI: 10.4236/jeas.2011.12003                

Abstract

Organic Light-Emitting diodes (OLEDs) are extremely sensitive to water vapour and oxygen, which causes rapid degradation. Epoxy and cover glass with large amount of desiccant are commonly applied to encapsulate bottom emitting OLEDs which is not a viable option for flexible as well as top emitting OLEDs. This paper reports a completely organic encapsulating layer consisting of four periods of alternate stacks of two organic materials with different morphologies deposited by simple vacuum thermal evaporation technique. Standard green OLED structures with and without encapsulation were fabricated and investigated using structural, optical and electrical studies. Moreover, the encapsulation presented being organic is safe for underlying organic layers in OLEDs and is ultrathin, transparent and without any cover glass and desiccant, ensuring its application in flexible and top emitting OLEDs.

Keywords

OLED, Thin Film Encapsulation, Diffusion Barrier, Atomic Force Microscopy

Conflicts of Interest

The authors declare no conflicts of interest.

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