AgNWs/Ga-doped ZnO 복합전극 적용 CdSe양자점 기반 투명발광소자

CdSe Quantum Dot based Transparent Light-emitting Device using Silver Nanowire/Ga-doped ZnO Composite Electrode

  • 박재홍 (부경대학교 디스플레이기술연구소) ;
  • 김효준 (부경대학교 융합디스플레이공학과) ;
  • 강현우 (부경대학교 융합디스플레이공학과) ;
  • 김종수 (부경대학교 디스플레이기술연구소) ;
  • 정용석 (부경대학교 융합디스플레이공학과)
  • Park, Jehong (Display Technology Research Center, Pukyong National University) ;
  • Kim, Hyojun (Department of Display Science and Engineering, Pukyong National University) ;
  • Kang, Hyeonwoo (Department of Display Science and Engineering, Pukyong National University) ;
  • Kim, Jongsu (Display Technology Research Center, Pukyong National University) ;
  • Jeong, Yongseok (Department of Display Science and Engineering, Pukyong National University)
  • 투고 : 2020.10.23
  • 심사 : 2020.12.08
  • 발행 : 2020.12.31

초록

The silver nanowires (AgNWs) were synthesized by the conventional polyol process, which revealed 25 ㎛ and 30 nm of average length and diameter, respectively. The synthesized AgNWs were applied to the CdSe/CdZnS quantum dot (QD) based transparent light-emitting device (LED). The device using a randomly networked AgNWs electrode had some problems such as the high threshold voltage (for operating the device) due to the random pores from the networked AgNWs. As a method of improvement, a composite electrode was formed by overlaying the ZnO:Ga on the AgNWs network. The device used the composite electrode revealed a low threshold voltage (4.4 Vth) and high current density compared to the AgNWs only electrode device. The brightness and current density of the device using composite electrode were 55.57 cd/㎡ and 41.54 mA/㎠ at the operating voltage of 12.8 V, respectively, while the brightness and current density of the device using (single) AgNWs only were 1.71 cd/㎡ and 2.05 mA/㎠ at the same operating voltage. The transmittance of the device revealed 65 % in a range of visible light. Besides the reliability of the devices was confirmed that the device using the composite electrode revealed 2 times longer lifetime than that of the AgNWs only electrode device.

키워드

참고문헌

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