Performance of flexible polymeric light-emitting diodes under bending conditions

Abstract

Organic light-emitting diodes were fabricated on a 125-μm-thick polyethylene terephthalate substrate covered with 100 nm indium tin oxide. The luminance–current–voltage performance and the emission spectrum of the devices are investigated in the bent state under mechanical stress at different bending radii. Down to a curvature of 15 mm, no significant decrease in the device performance is found compared to the relaxed state, as well as to conventional devices on glass substrates.

Fabrication of Highly Conductive Poly(3,4‐ethylenedioxythiophene) Films by Vapor Phase Polymerization and Their Application in Efficient Organic Light‐Emitting Diodes

“…Attempts have also been made at implementing ITO in an emerging generation of flexible devices, but it is not an ideal choice owing to its inherent brittleness and susceptibility to conductivity changes after bending. [3][4][5] When this is considered alongside the ever-increasing cost of indium, it is clear that there is a pressing need to develop organic-based electrode materials for both flexible and rigid substrate devices. Here, we report the synthesis and optoelectronic properties of highly conductive (≤ 1180 S cm -1 ) poly(3,4-ethylenedioxythiophene) (PEDOT) films prepared by vapor phase polymerization (VPP).…”

Highly Conductive Polymer Anodes as Replacements for Inorganic Materials in High‐Efficiency Organic Light‐Emitting Diodes

“…[7,9] For applications using flexible substrates, inorganic anodes such as ITO fail to provide stable anode properties, mainly because of their brittleness. [10] To reduce the roughness of ITO films, an additional poly (3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT:PSS) layer can be applied to the ITO anode to make it smooth. This polymer layer also acts as a hole-injection layer for the molecular stack deposited on top of it.…”

Silver grid transparent conducting electrodes for organic light emitting diodes

“…Finally, ITO is also brittle, which is at odds with the mechanical flexibility of OLEDs [4] and other organic electronics.…”