Spectrum Change of Blue Phosphorescent Organic Light Emitting Diodes with CBP and FIrpic

摘要

In the blue phosphorescent organic light emitting devices (phOLEDs) with CBP:FIrpic, the relative intensity change of two peak, 465nm and 495nm were analyzed as degradation. As device is maintained on state, peak of 500nm is relatively increased than 465nm. It seems that these phenomena are induced by microcavity effect due to recombination region shift. As device is continuously driven, carrier blocking property of BCP is deteriorated and then recombination region is changed. Also the low triplet blocking property due to degradation of BCP let the EL spectrum to shift toward long wavelength and broaden.