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Recent Progress in High-Luminance Quantum Dot Light-Emitting Diodes

  • Rhee, Seunghyun (Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center (ISRC), Seoul National University) ;
  • Kim, Kyunghwan (Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center (ISRC), Seoul National University) ;
  • Roh, Jeongkyun (Department of Electrical Engineering, Pusan National University) ;
  • Kwak, Jeonghun (Department of Electrical and Computer Engineering, Inter-university Semiconductor Research Center (ISRC), Seoul National University)
  • Received : 2020.03.11
  • Accepted : 2020.03.26
  • Published : 2020.06.25

Abstract

Colloidal quantum dots (QDs) have gained tremendous attention as a key material for highly advanced display technologies. The performance of QD light-emitting diodes (QLEDs) has improved significantly over the past two decades, owing to notable progress in both material development and device engineering. The brightness of QLEDs has improved by more than three orders of magnitude from that of early-stage devices, and has attained a value in the range of traditional inorganic LEDs. The emergence of high-luminance (HL) QLEDs has induced fresh demands to incorporate the unique features of QDs into a wide range of display applications, beyond indoor and mobile displays. Therefore it is necessary to assess the present status and prospects of HL-QLEDs, to expand the application domain of QD-based light sources. As part of this study, we review recent advances in HL-QLEDs. In particular, based on reports of brightness exceeding 105 cd/㎡, we have summarized the major approaches toward achieving high brightness in QLEDs, in terms of material development and device engineering. Furthermore, we briefly introduce the recent progress achieved toward QD laser diodes, being the next step in the development of HL-QLEDs. This review provides general guidelines for achieving HL-QLEDs, and reveals the high potential of QDs as a universal material solution that can enable realization of a wide range of display applications.

Keywords

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