Top emitting poly(p-phenylene vinylene) light-emitting diodes on metal sandwiched polyethylene terephthalate substrates

Flexible poly(p-phenylene vinylene) organic light-emitting diodes (OLEDs) with top-emitting architecture were developed on metal-sandwiched polyethylene terephthalate (PET) substrates. Commercial aluminum-laminated PET (Al-PET) was adopted as initial substrates. Different kinds of metal layers (silver and nickel) were then deposited on Al-PET foil to form metal-sandwiched plastic substrates and also to serve as anodes for the top emitting OLEDs. Interface modification was employed to enhance carrier injection from the metal anodes to the polymeric organic stack. Semitransparent top cathodes were used for the flexible top-emitting diodes. The performance of these OLEDs was characterized and compared among different metal anodes. The flexible top-emitting OLEDs on metal-sandwiched PET foil can be bent to a substantial degree without breaking. Moreover, increased contrast ratio of OLEDs can be achieved with specific anodes due to lower reflectance of nickel material.