Modifications of ITO Surfaces in Organic EL Devices by $O_2$ Plasma Treatment

O$_2$ 플라즈마 처리에 의한 ITO 표면개질 변화에 따른 유기 EL 소자 특성

  • Published : 2003.06.01


We investigated the effect of oxygen plasma treatment of indium-tin oxide(ITO) surface on the performance of electroluminescence(EL) devices. ITO surface treated oxygen plasma has been analyzed using atomic force microscope(AFM) and X-ray photoelectron spectroscopy(XPS), to investigate the relations between the properties of the ITO surface and the properties of the current-voltage-luminance(I-V-L) characteristics of the fabricated OLED with the structure of ITO(plasma treatment) / TPD / Alq$_3$/ Al. It is found that the oxygen plasma treatment of ITO anode improve the hole injection of the OLED due to the modification of the surface states. The treated ITO anode nay be low voltage with high luminance efficiency.


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