High-current stressing of organic light-emitting diodes with different electron-transport materials |
| |
| Affiliation: | 1. School of Electrical and Electronic Engineering, Hubei Provincial Key Laboratory of Green Materials for Light Industry, Hubei University of Technology, Wuhan 430068, China;2. Department of Computer Science and Electrical Engineering, West Virginia University Morgantown, WV 26506, USA;1. Erich Schmid Institute of Materials Science, Austrian Academy of Sciences, Jahnstrasse 12, Leoben, Austria;2. Vienna University of Technology, Institute of Chemical Technologies and Analytics, Vienna, Austria;3. Christian Doppler Laboratory for Lifetime and Reliability of Interfaces in Complex Multi-Material Electronics, CTA, TU Wien, Vienna, Austria;4. Infineon Technologies Austria AG, Villach, Austria;5. Infineon Technologies Germany AG, Regensburg, Germany;6. Kompetenzzentrum Automobil- und Industrie-Elektronik GmbH, Villach, Austria |
| |
| Abstract: | We conducted accelerated reliability tests of electron-only devices (EODs) and organic light-emitting diodes (OLEDs) differing only in their electron-transport material (ETM). High current stressing of EODs at 50 mA/cm2 showed that Bphen ~ Alq3 > TPBi > TAZ in terms of intrinsic material stability. In addition, the lowest unoccupied molecular orbital (LUMO) level and electron mobility have been identified as two other key material factors affecting the degradation rate of OLEDs. TAZ has a low electron mobility, a LUMO level misaligned with the Fermi level of the cathode, and poor material stability, leading to extremely poor reliability of devices with a TAZ electron-transport layer (ETL). In contrast, the OLED with a Bphen ETL exhibited more stable operation and a 76 × longer luminance lifetime. Due to its relatively high electron mobility and good stability as well as perfect energy level alignment with the cathode, Bphen has proven to be the most desirable ETM from the standpoint of OLED reliability. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
