title: Enhanced performance on polymeric light-emitting diode with non-metallic ion in the water soluble non-conjugated polymer.
abstract: We have fabricated a polymer light-emitting diode (PLED) from the conventional blue-emitting polymer, polyfluorene (PFO), by constructing a multilayer structure with non-metal ion containing water soluble non-conjugated polymer, polyurethane with F- ion (PU:F-), on the top of the PFO. The device with PU:F- layer shows a maximum luminance of 5294 cd/m2 at an applied voltage of 10 V while the one without PU:F- layer shows only 4439 cd/m2 at the same applied voltage. We propose the improvement of device performance with PU:F- layer was due to not only an effective hole blocking at the polymer-polymer interface but also increase of electric field strength with anode after electro-stactic repulsion between electrons from the cathod and anions from the water soluble polymer layer. We will discuss the effect of multilayer polymer structure in PLED in terms of current/voltage characteristics, luminance, and quantum efficiency related with the applied bias.
authors.forename: Chung-Gi
authors.initials: CG
authors.lastname: Kim
authors.forename: Min-Sik
authors.initials: MS
authors.lastname: Koo
authors.forename: Dong-Hun
authors.initials: DH
authors.lastname: Lee
authors.forename: Tae-Woo
authors.initials: TW
authors.lastname: Kwon
authors.forename: Seong-Jin
authors.initials: SJ
authors.lastname: Cho
authors.forename: Taek
authors.initials: T
authors.lastname: Ahn
authors.forename: Hyung-Suk
authors.initials: HS
authors.lastname: Woo
authors.forename: Dong-Kyu
authors.initials: DK
authors.lastname: Park