Physics Journal of the Indonesian Physical Society
EFFECT OF ORGANIC LAYER THICKNESS ON PERFORMANCE OF ITO/MPB/ALQ3/AL LIGHT EMITTING DIODE STRUCTURE
Mursyidah1, M.M. Salleh1, M. Yahaya1 and R Daik2
1School of Applied Physics, Faculty of Science and TechnologyUniversiti Kebangsaan, Malaysia
2School of Chemical Science and Food TechnologyFaculty of Science and TechnologyUniversiti Kebangsaan Malaysia
Organic light emitting diodes made with N,N'-Bis(3-methylphenyl)-N-N' diphenyl benzidine (MPB) and tris (8-quinolinolato) aluminum (Alq3) were fabricated. Both organic thin films were sandwiched between two electrodes with ITO/MPB/Alq3/Al structure. MPB thin film used as a hole-transporting layer, and Alq3 as a luminescent layer, which predominantly transports electrons. The effects of MPB and Alq3 layer thickness on performance of organic light emitting devices have been investigated. Optimum brightness was obtained for the device with 60 nm Alq3 film. The effect of the thickness of MPB layer on the operating voltage was studied through the current-voltage (I-V) curves. It was found that the turn-on voltage increases with increasing the MPB layer thickness.