랭뮤어-블롯젯을 통해 형성된 고밀도 양자점 박막과 이를 기반으로 한 발광다이오드
Light-emitting Diodes based on a Densely Packed QD Film Deposited by the Langmuir-Blodgett Technique
1
조회
0
다운로드
0
인용
0
참고문헌
키워드
초록
To achieve high-performance colloidal quantum dot light-emitting diodes (QD-LEDs), the use of a densely packed QD film is crucial to prevent the formation of leakage current pathways and increase in interface resistance. Spin coating is the most common method to deposit QDs; however, this method often produces pinholes that can act as short-circuit paths within devices. Since state-of-the-art QD-LEDs typically employ mono- or bi-layer QDs as an emissive layer because of their low conductivities, the use of a densely packed and pinhole-free QD film is essential. Herein, we introduce the Langmuir-Blodgett (LB) technique as a deposition method for the fabricate densely packed QD films in QD-LEDs. The LB technique successfully transfers a highly dense monolayer of QDs onto the substrate, and multilayer deposition is performed by repeating the transfer process. To validate the comparability of the LB technique with the standard QD-LED fabrication process, we fabricate and compare the performance of LB-based QD-LEDs to that of the spin-coatingbased device. Owing to the non-destructiveness of the LB technique, the electroluminescence efficiency of the LB-based QD-LEDs is similar to that of the standard spin coating-based device. Thus, the LB technique is promising for use in optoelectronic applications.
Abstract
To achieve high-performance colloidal quantum dot light-emitting diodes (QD-LEDs), the use of a densely packed QD film is crucial to prevent the formation of leakage current pathways and increase in interface resistance. Spin coating is the most common method to deposit QDs; however, this method often produces pinholes that can act as short-circuit paths within devices. Since state-of-the-art QD-LEDs typically employ mono- or bi-layer QDs as an emissive layer because of their low conductivities, the use of a densely packed and pinhole-free QD film is essential. Herein, we introduce the Langmuir-Blodgett (LB) technique as a deposition method for the fabricate densely packed QD films in QD-LEDs. The LB technique successfully transfers a highly dense monolayer of QDs onto the substrate, and multilayer deposition is performed by repeating the transfer process. To validate the comparability of the LB technique with the standard QD-LED fabrication process, we fabricate and compare the performance of LB-based QD-LEDs to that of the spin-coatingbased device. Owing to the non-destructiveness of the LB technique, the electroluminescence efficiency of the LB-based QD-LEDs is similar to that of the standard spin coating-based device. Thus, the LB technique is promising for use in optoelectronic applications.
참고문헌 (12)
- J. Kwak, "Bright and efficient full-color colloidal quantum dot light-emitting diodes using an inverted device structure", Nano Lett, 12(5), pp.2362~2366 (2012)
- J. M. Pietryga, "Spectroscopic and device aspects of nanocrystal quantum dots", Chem. Rev, 116(18), pp.10513~10622 (2016)
- Seunghyun Rhee, "Recent Progress in High-Luminance Quantum Dot Light-Emitting Diodes", Current Optics and Photonics, 4(3), pp.161~173 (2020), 한국광학회[DOI]
- S. Rhee, "Steering interface dipoles for bright and efficient all-inorganic quantum dot based light-emitting diodes", ACS Nano, 15(12), pp.20332~20340 (2021)
- S. H. Kim, "A bioinspired stretchable sensory-neuromorphic system", Adv. Mater, 33(44), pp.2104690~ (2021)
- G. W. Baek, "Highly efficient, surface ligand modified quantum dot light-emitting diodes driven by type-controllable MoTe2 thin film transistors via electron charge enhancer", Adv. Electron. Mater, 7(10), pp.2100535~ (2021)
- S. Rhee, "Positive incentive"approach to enhance the operational stability of quantum dot-based light-emitting diodes", ACS Appl. Mater. Interfaces, 11(43), pp.40252~40259 (2019)
- S. Rhee, "Tailoring the electronic landscape of quantum dot light-emitting diodes for high brightness and stable operation", Acs Nano, 14(12), pp.17496~17504 (2020)
- S. Acharya, "Soft Langmuir–Blodgett technique for hard nanomaterials", Adv. Mater, 21(29), pp.2959~2981 (2009)
- S. Rhee, "Polarized electroluminescence emission in high-performance quantum rod light-emitting diodes via the LangmuirBlodgett technique", Small, 17(32), pp.2101204~ (2021)
- J. Roh, "Optically pumped colloidal-quantum-dot lasing in LED-like devices with an integrated optical cavity", Nat. Commun, 11(1), pp.1~10 (2020)
- Y. -S. Park, "Colloidal quantum dot lasers", Nat. Rev. Mater, 6(5), pp.382~401 (2021)