A Study on the Enhancement of Emission Efficiency of an Organic EL Devices Using the RF Plasma

RF 플라즈마를 이용한 유기 EL소자의 발광 효율에 관한 연구

  • 박상무 (인하대 전기공학과) ;
  • 김형권 (한국소방검정공사) ;
  • 신백균 ;
  • 임경범 (인하대 전기공학과) ;
  • 이덕출 (인하대 전기공학과)
  • Published : 2003.09.01

Abstract

Efficient electrodes are devised for organic luminescent device(OLED). ITO electrode is treated with $O_2$ plasma. In order to inject hole efficiently, there is proposed the shape of anode that inserted plasma polymerized films as buffer layer between anode and organic layer using thiophene monomer. In the case of device inserted the buffer layer by using the plasma polymerization after $O_2$ plasma processing for ITO transparent electrode, since it forms the stable interface and reduce the moving speed of hole, the recombination of hole and electronic are made in the emitting layer. Therefore it realized the device capability of two times in the aspect of luminous efficiency than the device which do not be inserted the buffer layer. Experiments are limited to the device that has the structure of TPD/$AIq_3$, however, the aforementioned electrodes can similarly applied to the organic luminous device and the Polymer luminous device.

Keywords

oxygen plasma treatment;plasma polymerization;OLED;electroluminescence(EL)

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