Solid State Science and Technology, Vol. 16, No 1 (2008) 188-196

ISSN 0128-7389

Corresponding Author:





Suhaila Sepeai, Muhamad Mat Salleh, Muhammad Yahaya

Institute of Microengineering and Nanoelectronics (IMEN)

Universiti Kebangsaan Malaysia,43600 Bangi, Selangor, MALAYSIA



OLED devices with the structure of ITO/PHF:rubrene/Al have been fabricated, where

PHF is poly(9,9-di-n-hexylfluorenyl-2,7-diyl) and rubrene is 5,6,11,12-

tetraphenylnapthacene. PHF is used as blue light emitting host and rubrene as an orange

dye dopant. The devices were fabricated with a variations of PHF and rubrene

concentration to obtained an optimum white light. The PHF doped rubrene thin films

were deposited using spin coating technique. The performance of the devices was

determined from measurement of CIE coordinate, current-voltage curve, and brightness.

The results showed that the combination of 0.6 wt% PHF and 0.06 wt% rubrene

produced the optimum white light at CIE coordinate of (0.30,0.33). The standard

coordinate for white light is (0.33, 0.33). The turn-on voltage of this device is 14.0 V

and the brightness is 6583 cd/m2. In order to reduce the turn-on voltage, the devices

were annealed at variation temperatures of 50C, 100C, and 150C. The best annealing

temperature is 150C where it successfully reduced the turn-on voltage to 8.0 V and

increased the brightness to 9042 cd/m2.



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