Barrier performance optimization of atomic layer deposited diffusion barriers for organic light emitting diodes using x-ray reflectivity investigations

摘要

The importance of O_3 pulse duration for encapsulation of organic light emitting diodes (OLEDs) with ultra thin inorganic atomic layer deposited AI_2O_3 layers is demonstrated for deposition temperatures of 50 ℃. X-ray reflectivity (XRR) measurements show that O_3 pulse durations longer than 15 s produce dense and thin Al_2O_3 layers. Correspondingly, black spot growth is not observed in OLEDs encapsulated with such layers during 91 days of aging under ambient conditions. This implies that XRR can be used as a tool for process optimization of OLED encapsulation layers leading to devices with long lifetimes.