Transparent OLED displays for selective bidirectional viewing using ZnO/Yb:Ag cathode with highly smooth and low-barrier surface

Eun-young Choi; Sung-Cheon Kang; Kanghoon Kim; Su-Hyeon Lee; Jeong-Beom Kim; Jang-Kun Song

doi:10.1038/s41377-024-01739-0

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Transparent OLED displays for selective bidirectional viewing using ZnO/Yb:Ag cathode with highly smooth and low-barrier surface

Original Articles

- Transparent OLED displays for selective bidirectional viewing using ZnO/Yb:Ag cathode with highly smooth and low-barrier surface
- Light: Science & Applications Vol. 14, Issue 3, Pages: 673-683(2025)
- Affiliations：
  
  1.Department of Electrical and Computer Engineering, Sungkyunkwan University, Suwon-si, Republic of Korea
  2.Department of Semiconductor and Display Engineering, Sungkyunkwan University, Suwon-si, Republic of Korea
- Author bio：
  
  Jang-Kun Song (jk.song@skku.edu)
- Funds：
- DOI：10.1038/s41377-024-01739-0
  CLC：
- Received：25 July 2024，
  
  Revised：25 December 2024，
  
  Accepted：2024-12-30，
  
  Published Online：24 January 2025，
  
  Published：31 March 2025
- Accepted：
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Choi, E. Y. et al. Transparent OLED displays for selective bidirectional viewing using ZnO/Yb:Ag cathode with highly smooth and low-barrier surface. Light: Science & Applications, 14, 673-683 (2025).
DOI：

Choi, E. Y. et al. Transparent OLED displays for selective bidirectional viewing using ZnO/Yb:Ag cathode with highly smooth and low-barrier surface. Light: Science & Applications, 14, 673-683 (2025). DOI： 10.1038/s41377-024-01739-0.

摘要

Abstract

Transparent organic light-emitting diode (TrOLED) displays represent cutting-edge technology posed to significantly enhance user experience. This study addresses two pivotal challenges in TrOLED development. Firstly

we focus on the innovation of transparent cathodes

a fundamental component in TrOLEDs

by introducing a ZnO/Yb:Ag cathode. This cathode employs a combination of seed layer and metal doping techniques to achieve a highly uniform surface morphology and a low surface energy barrier. The optimized Yb:Ag cathode on ZnO

with a mere thickness of 15 nm

exhibits remarkable properties: an extremely low surface roughness of 0.52 nm

sheet resistance of 11.6 Ω ϒ

−1

an optical transmittance of 86.7% at 510 nm

and tunable work function (here

optimized to be 3.86 eV)

ensuring superior electron injection capability. Secondly

we propose a novel TrOLED pixel structure that features selective bidirectional viewing

allowing different types of information to be selectively displayed on each side while preserving overall transparency and minimizing pixel complexity. This design innovation distinguishes itself from conventional TrOLEDs that display images on only one side. The bidirectional TrOLED design not only enhances openness and esthetic appeal but also holds promise for diverse applications across various user environments.

关键词

Keywords

references

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