Xi J.-F.,Shaanxi Engineering Center for Display Devices |
Xi J.-F.,Shaanxi University of Science and Technology |
Zhang F.-H.,Shaanxi Engineering Center for Display Devices |
Zhang F.-H.,Shaanxi University of Science and Technology |
And 3 more authors.
Guang Pu Xue Yu Guang Pu Fen Xi/Spectroscopy and Spectral Analysis | Year: 2011
It is demonstrated that the panchromatic luminescence devices with organic blue-emissive light-emitting was fabricated. This technique used down conversion, which was already popular in inorganic power LEDs to obtain white light emission. A blue OLED device with a configuration of ITO/2T-NATA(30 nm)/AND:TBPe(50 Wt%, 40 nm)/Alq3(100 nm)/LiF(1 nm)/Al(100 nm) was prepared via vacuum deposition process, and then coated with YAG:Ce phosphor layers of different thicknesses to obtain a controllable and uniform shape while the CIE coordinates were fine tuned. This development not only decreased steps of technics and degree of difficulty, but also applied the mature technology of phosphor. The results showed that steady spectrogram was obtained in the devices with phosphor, with a best performance of a maximum luminance of 13840 cd·m-2 which was about 2 times of that of the devices without phosphor; a maximum current efficiency of 17.3 cd·A-1 was increased more two times more than the devices without phosphor. The emission spectrum could be adjusted by varying the concentration and thickness of the phosphor layers. Absoulte spectrogram of devices was in direct proportion with different driving current corresponding.