Improving organic/electrode interface in organic light-emitting diodes by soft contact Iamination

Abstract

Organic light-emitting diodes (OLEDs), with few exceptions, are fabricated in the standard way of sequentially depositing active layers and electrodes onto a substrate. The conventional devices have 'a detrimental layer' at the interface between the organic and the top metal electrode because evaporation results in metal in-diffusion and chemical disruption at the metal-organic interface. Here, a different approach is introduced to construct OLEDs: soft contact lamination (SCL) is based on physical lamination of thin metal electrodes supported by an elastomeric layer against the electroluminescent organic layer. This method produces spatially homogeneous, intimate contacts via van der Waals interaction between the metal and the organic, resulting in no chemical and physical damages to the organic. Devices fabricated by SCL are shown to have no detrimental layer and fewer luminescence-quenching channels than conventional devices that have evaporated top metal electrodes.