Journal of the Semiconductor & Display Technology (반도체디스플레이기술학회지)

The Korean Society Of Semiconductor & Display Technology (한국반도체디스플레이기술학회)
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Improved On-off Property of SiO2 Embedded Polyfluorene Polymer-OLED

SiO2의 첨가를 통한 Polyfluorene계 Polymer-OLED의 발광 동작 개선 가능성

  • Jeon, Byung Joo (Dept. of LED Convergence Engineering, Specialized Graduate School of Science and Technology Convergence, Pukyong National University) ;
  • Kim, Hyo Jun (Dept. of Display Science and Engineering, Pukyong National University) ;
  • Kim, Jong Su (Dept. of LED Convergence Engineering, Specialized Graduate School of Science and Technology Convergence, Pukyong National University) ;
  • Jeong, Yong Seok (Dept. of Display Science and Engineering, Pukyong National University)
  • 전병주 (부경대학교 과학기술융합전문대학원 LED융합공학) ;
  • 김효준 (부경대학교 융합디스플레이공학과) ;
  • 김종수 (부경대학교 과학기술융합전문대학원 LED융합공학) ;
  • 정용석 (부경대학교 융합디스플레이공학과)
  • Received : 2017.03.07
  • Accepted : 2017.03.24
  • Published : 2017.03.31
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Abstract

The effect of weak dielectric silicone dioxide($SiO_2$) embedded in polyfluorene(PFO) emitting layer of polymer-based multi structure OLED was investigated. Indium tin oxide(ITO)/poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS)/poly(9,9-di-n-octylfluorenyl-2,7-diyl)(PFO)/2,2,2"-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi)/aluminum(Al) structure OLED was fabricated by spin-coating method. Applied electric field causes some effect on $SiO_2$ in PFO layer. Thus, interaction between polymers and affected $SiO_2$ might generate electrical and luminance properties change. Experimental results, show the reduced threshold voltage of 6 V(from 23 V to 17 V). The maximum current density was rather increased from $71A/m^2$ to $610A/m^2$ and maximum brightness was also increased from $7.19cd/m^2$ to $41.03cd/m^2$, 9 and 6 times each. Additionally we obtained colour broadening result due to the increasing of blue-green band emission. Consequently we observed that electrical and luminance properties are enhanced by adding $SiO_2$ and identified the possibility of controlling the emission colour of OLED device according to colour broadening.

Keywords

References

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