Top-emitting organic light-emitting diodes integrated with thermally evaporated scattering film for reducing angular dependence of emission spectra

• A thermally evaporated scattering film based on TPE is developed.
• The TPE scattering film can be integrated with top-emitting OLEDs directly.
• Top-emitting OLEDs with TPE-scattering film exhibit improved angular stability.

A scattering film is obtained by thermally evaporating tetraphenylethene (TPE) onto the substrate. The TPE molecules self-crystallize themselves as microsheet on reaching the substrate. The resultant TPE films exhibit strong light scattering effect because of the random distribution of the crystallized sheets. The scattering films, being able to be deposited by thermal evaporation, can thus integrate with top-emitting organic light-emitting diodes (OLEDs) directly. As a result, the top-emitting OLEDs exhibit reduced angular dependence of emission spectra; for example, the color coordinates is only slightly shifted from (0.2891, 0.6001) to (0.2735, 0.5617) when the viewing angle increases from 0° to 80°.

Figure optionsDownload as PowerPoint slide