[8a-PA3-1~27] 12.4 Organic light-emitting devices and organic transistors

▲ [8a-PA3-6] Indium diffusion mapping by GCIB-UPS/XPS in continuously operated OLEDs

〇HINWAI MO¹, Yasuhiro Hatae¹, Shin-ichiro Kobayashi¹, Terashima Masahiro³, Takuya Miyayama³, Hiroshi Fujimoto^1,2, Chihaya Adachi^1,2 (1.i3-opera, 2.opera, 3.ULVAC-PHI)

Keywords:Organic light-emitting diodes, Device Degradation

Understanding the degradation mechanism of organic LEDs is important in fabricating long-lived high efficiency devices. Previous studies about degradation mechanism by using GCIB-TOF-SIMS suggested a novel way for device physics analysis. Here, we analyzed the interfacial electronics states between the initial and degraded device by GCIB-UPS/XPS. We mapped the atomic concentration of different elements (C, Al, In, Sn) across the organic layer. Metal atom was found to be diffusing across the organic layer. For further studies, trap analysis was carried out by thermally stimulated current (TSC). Energy level diagram by GCIB-UPS and displacement current measurement (DCM) result suggested there existed an extra hole injection barrier. We concluded that GCIB-UPS/XPS is one of the useful tools in studying device physics among device degradation.