Presentation Information
[22p-P02-4]Measurements of potential distribution changes in OLEDs before and after degradation by applying voltage
〇(PC)Yusei Sasaki1, Kazuo Yamamoto1,2, Satoshi Anada1, Noriyuki Yoshimoto2 (1.JFCC, 2.Iwate Univ.)
Keywords:
OLED,TEM,electron holography
Understanding the degradation process of OLEDs is important for improving their lifetime and luminous efficiency. In this study, we used electron holography, which is a potential measurement method using a transmission electron microscope, to measure the electric potentials in OLEDs before and after degradation induced by applying voltage. The devices after degradation showed an increase in film thickness and a decrease of potential difference in the organic layers consisting of α-NPD and Alq3. This study enabled us to visualize the changes in device structure and potential distribution accompanying the degradation induced by applying voltage.