Tandem Organic Light‐Emitting Diode using Hexaazatriphenylene Hexacarbonitrile in the Intermediate Connector

Abstract

Tandem organic light-emitting diodes (OLEDs) with an organic–organic intermediate connector, consisting of an n-type doped electron-transporting layer (e.g. Li-doped Alq as shown in the figure) and nondoped hexaazatriphenylene hexacarbonitrile (HAT-CN), exhibit reduced drive voltage, improved voltage stability, and improved power efficiency. Moreover, this intermediate connector can be formed by thermal evaporation at temperatures lower than 300 °C, which simplifies the fabrication process of the OLEDs.