Article
Materials Science, Multidisciplinary
Liwen Deng, Xiang Zhang, Yinguo Yan, Yuze Xiao, Ziming Yao, Enguo Chen, Sheng Xu, Yun Ye, Jie Sun, Qun Yan, Tailiang Guo
Summary: Pixelated quantum dot color conversion layer (PQDCCL) is a promising approach for full-color micro-LED displays. However, the QD excitation by ambient light affects the contrast ratio and readability of the display, and this issue has not been fully explored. This paper establishes theoretical models to analyze the contrast ratio of a micro-LED display and validates it through simulation and experiments. The results show the potential of the proposed model for QD-based micro-LED displays and provide support for estimating the contrast ratio of self-luminous color-converted displays.
RESULTS IN PHYSICS
(2023)
Article
Chemistry, Analytical
Bingxin Zhao, Qingqian Wang, Depeng Li, Hongcheng Yang, Xue Bai, Shang Li, Pai Liu, Xiaowei Sun
Summary: This work demonstrated a method for fabricating color-conversion layers of red and green quantum dots color filters for full-color display arrays. By treating quantum dots with a compound containing epoxy functional groups and combining them with a photo-initiator, the protective function of quantum dots was achieved, and the pixel size of green quantum dot color filters was successfully reduced with a high optical density.
Article
Chemistry, Multidisciplinary
Tzu-Yi Lee, Wen-Chien Miao, Yu-Ying Hung, Yi-Hong Bai, Pei-Tien Chen, Wei-Ta Huang, Kuan-An Chen, Chien-Chung Lin, Fang-Chung Chen, Yu-Heng Hong, Hao-Chung Kuo
Summary: This study proposes a novel structural design that combines blue and quantum well (QW)-intermixing ultraviolet (UV)-hybrid μ-LEDs to achieve high color-conversion efficiency (CCE). Through simulations, various combinations of QD and TiO2 concentrations and thickness variations are examined for their impact on photoluminescence efficiency (PLQY). The resulting high-efficiency color-conversion layer (CCL) saves time and material costs and enhances light absorption and illumination uniformity. The research also introduces a passivation protection layer and a modified distributed Bragg reflector (DBR) to improve device reliability and achieve high CCE values.
Article
Engineering, Electrical & Electronic
Pengsen Lin, Xiaoxiao Ji, Xinyi Wang, Luqiao Yin, Jianhua Zhang
Summary: This article investigates the effects of different reflectivity (0%-50%) of doped scattering particles on the light extraction efficiency and optical crosstalk of Micro-light-emitting diodes (Micro-LEDs). By using the optical simulation software Tracepro, the light extraction efficiency and optical crosstalk of the scattering particles with different reflectivity were simulated and evaluated. The results show that increasing the reflectivity of the doped scattering particles can increase the optical efficiency, but increasing the reflectivity first decreases and then increases the optical crosstalk.
IEEE TRANSACTIONS ON ELECTRON DEVICES
(2023)
Review
Materials Science, Multidisciplinary
Junchi Chen, Qiliang Zhao, Binhai Yu, Uli Lemmer
Summary: Mini/microlight-emitting diodes (LEDs) are a promising technology for next-generation displays. Combining blue nitride-based LEDs with quantum dots (QDs) as color conversion materials shows potential for achieving full-color displays. However, there are challenges in terms of QD material stability, dispersion quality, light extraction, and mass manufacturing strategies, which hinder the widespread application of QDs in display technologies. This review summarizes recent research on QD materials for color conversion display and discusses packaging strategies, light management approaches, and pixelation methods to address these challenges for mini/micro-LED-based displays.
ADVANCED OPTICAL MATERIALS
(2023)
Review
Chemistry, Multidisciplinary
Jung-El Ryu, Sohyeon Park, Yongjo Park, Sang-Wan Ryu, Kyungwook Hwang, Ho Won Jang
Summary: The implementation of high-efficiency and high-resolution displays has been a research focus. Micro-LEDs, as promising display technology, have advantages over other displays. Challenges including low quantum efficiency, time-consuming transfer, and complex color conversion have been overcome with technological breakthroughs. This review presents current status and critical challenges of micro-LED technology and promising technical breakthroughs for commercialization of high-performance displays.
ADVANCED MATERIALS
(2023)
Article
Engineering, Electrical & Electronic
Dacheng Mao, Zheshun Xiong, Matthew Donnelly, Guangyu Xu
Summary: The study introduced a simple fabrication method for high-density, two-color quantum dot-based micro-LED arrays, which can be used for bi-directional optogenetics at the cellular level. The array featured small-sized light spots with high optical power density, along with low crosstalk and fast response.
IEEE ELECTRON DEVICE LETTERS
(2021)
Article
Chemistry, Analytical
Panyuan Li, Jin Tao, Yongzhou Zhao, Yifang Sun, Kaili Fan, Licai Zhu, Wenchao Sun, Jinguang Lv, Yuxin Qin, Qiang Wang, Qinghui Zeng, Weibiao Wang, Shurong Wang, Jingqiu Liang
Summary: This article explores the incorporation of red and green perovskite quantum dots into a flexible color-conversion layer using microfluidics. The integration of the flexible color-conversion layer with a blue micro-LED enables the realization of a full-color display with a pixel pitch of 200 μm. The use of perovskite quantum dots offers advantages such as high quantum yield, tunable wavelength, and high stability, making it a promising technology for the development of flexible micro-displays.
Article
Materials Science, Multidisciplinary
Asim Onal, Guncem Ozgun Eren, Rustamzhon Melikov, Lokman Kaya, Sedat Nizamoglu
Summary: In recent years, quantum dots (QDs) have emerged as a powerful building block for liquid-crystal display (LCD) technology, particularly in the form of color enhancement films. However, the challenge remains to develop efficient and wide color gamut LEDs for backlighting purposes. This study presents QD-based white LEDs that exhibit a high external quantum efficiency (EQE) of 39.8% and a wide NTSC color gamut coverage of 133.3%. These LEDs utilize giant CdSe/CdS core/shell QDs for red-emitting spectral range and green-emitting CdZnSeS/ZnS alloyed core/shell QDs, resulting in high photoluminescence quantum yield (PLQY) and narrow full width at half maximum (FWHM) values. The incorporation of QDs in liquid matrix on blue LED chips for LCD TV backlighting improves image brightness and color vibrancy, showcasing the potential of QD-based white LEDs for next-generation display technology.
ADVANCED MATERIALS TECHNOLOGIES
(2023)
Review
Materials Science, Multidisciplinary
Teng Ma, Jun Chen, Ziyi Chen, Lumeng Liang, Jinning Hu, Weili Shen, Zhenhua Li, Haibo Zeng
Summary: This article introduces the excellent performance of Micro-LED as a new generation of display technology in the display market, and details the methods for achieving Micro-LED full-color display from a technical perspective, as well as the current research achievements and challenges.
ADVANCED MATERIALS TECHNOLOGIES
(2023)
Article
Materials Science, Multidisciplinary
Feng Qin, Cao Liu, Wenhui Wu, Wenxiang Peng, Sitao Huo, Jiandong Ye, Shulin Gu
Summary: In this study, a full-color Micro LED display with red and green quantum dot color conversion layers fabricated by inkjet printing was successfully developed, showing excellent performance.
ELECTRONIC MATERIALS LETTERS
(2023)
Article
Engineering, Electrical & Electronic
Feifan Xu, Tao Tao, Dongqi Zhang, Yang Zhang, Yimeng Sang, Junchi Yu, Ting Zhi, Zhe Zhuang, Zili Xie, Rong Zhang, Bin Liu
Summary: We have developed a simple method for producing green and red colors on GaN-based blue micro-light-emitting diodes (mu LEDs) by patterning quantum dots (QDs) using standard photolithography and dry etching. The fabricated QDs exhibited ultra-high resolution and throughput, with a minimum size of 2 μm on a 4-inch wafer. The individual color converted green and red mu LEDs achieved a peak external quantum efficiency (EQE) of 9.6% and 14.7%, respectively. We further demonstrated the monolithic integration of red, green, and blue (RGB) mu LEDs as a single pixel by sequentially patterning red and green QDs. The resulting RGB mu LEDs covered 83.4% of the Rec. 2020 color space in the CIE 1931 diagram. This method enables high-performance red/green mu LEDs with small feature sizes and scalable fabrication of full-color mu LED displays.
IEEE ELECTRON DEVICE LETTERS
(2023)
Article
Optics
Longheng Qi, Xu Zhang, Wing Cheung Chong, Kei May Lau
Summary: This paper demonstrates a monolithic full-color micro-LED microdisplay with a resolution of 423 pixels per inch by integrating a blue GaN-on-Si display module and a quantum dots photoresist color conversion module. The result is a full-color micro-LED display with a wide color gamut and high brightness. The prototype shows potential scalability and low-cost volume production of high-resolution full-color micro-LED microdisplays.
PHOTONICS RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Shenghan Zou, Yuzhi Li, Zheng Gong
Summary: This study demonstrates a method for producing quantum dot (QD) patterns with sufficient thickness for efficient color conversion in micro-LED displays. The technique combines replicate molding, plasma etching, and transfer printing to simplify the preparation of QD inks and minimize optical damage. Control of pixel resolution and thickness is achieved through the microstructures of the molding template and etching process. The resulting QD patterns show improved color conversion and have the potential for use in full-color micro-LED displays.
Article
Optics
Bingle Huang, Enguo Chen, Lei Sun, Tailiang Guo
Summary: This paper presents an effective approach for preparing quantum-dot color conversion films in white-balance display backlights. The theoretical adjustment method and experimental verification successfully achieved the target white balance.
OPTICS AND LASER TECHNOLOGY
(2022)
