基于纳米环/量子点结构的高效率Micro-LED全彩器件研究

Micro-LED is expected to be the candidate for the next generation display technology. Therefore, the research on three major aspects of micro-LED displays including the chip structure, the chip luminous efficiency and the quantum dot (QD) color conversion efficiency is important for improving the performance of QD based Micro-LED full-color displays. Firstly, the control principle of the nanoring structure on the emission wavelength is explored, and the optical performance model of the nanoring Micro-LED is constructed. Secondly, the mechanism and application effect of the atomic layer deposition (ALD) sidewall passivation technology on the chip luminous efficiency are explored. Then the theoretical model of the nonradiative resonant energy transfer for the massive improvement of the color conversion efficiency is studied. Based on these physical models, blue nanoring Micro-LEDs are fabricated in designated areas of a green epitaxial wafer. Next, the ALD sidewall passivation technology is utilized to improve the chip luminous efficiency. Then, red QDs are sprayed on some blue nanoring Micro-LEDs, and the dipole coupling between QDs and multi quantum wells considerably enhances the nonradiative resonant energy transfer which can significantly improve the color conversion efficiency of QDs. In this way, a Micro-LED full color display device based on the hybrid nanoring QD structure can be fabricated on a single epitaxial wafer to achieve high luminous efficiency and high color conversion efficiency.

Micro-LED被誉为下一代新型显示技术，针对芯片结构、芯片发光效率、量子点色转换效率这三个核心要素的研究对于提升量子点Micro-LED全彩显示的性能具有重要的科学意义。本项目首先探究纳米环结构对发光波长的调控机理并构建纳米环Micro-LED芯片的光学性能模型，其次探索原子层沉积（ALD）侧壁钝化技术对芯片发光效率的改善机理与应用效果，然后研究非辐射能量转移机制对量子点色转换效率提升的理论模型。基于上述理论基础，通过实验在绿光外延片的指定区域制备纳米环蓝光Micro-LED，再采用ALD侧壁钝化技术改善芯片发光效率，接着在部分蓝光纳米环上喷涂红色量子点，利用量子点和量子阱之间的偶极子耦合来增强非辐射能量转移机制并提升量子点色转换效率，制备出纳米环/量子点结构的单片式集成Micro-LED全彩显示器件，实现高发光效率与高色转换效率，推进量子点Micro-LED全彩显示的规模化应用。

Micro-LED是下一代新型显示技术的重要组成部分，与市场上成熟的液晶显示（LCD）与有机发光二极管显示（OLED）相比，Micro-LED在亮度、能耗、对比度、分辨率、色彩呈现、响应速度等方面的都具有明显优势。因此，Micro-LED显示技术已经成为显示领域近年来的热点研究课题。此外，Micro-LED全彩显示技术也有望同可见光通信（VLC）技术结合以进一步实现Micro-LED的多样化应用。.针对芯片结构、芯片发光效率、色转换层性能这三个核心要素的研究对于提升Micro-LED全彩显示的性能具有重要的科学意义。本项目首先探究半极性Micro-LED结合钙钛矿量子点色转换层在全彩显示和VLC领域的应用前景，其次探索原子层沉积（ALD）的侧壁钝化技术对Micro-LED芯片发光性能的提升效果，然后研究基于量子点色转换层的全无机包覆路线与响应速度提升方法。基于上述理论基础，首先在Micro-LED芯片制备方面通过实验制备了高性能半极性蓝光Micro-LED，并采用ALD侧壁钝化技术改善芯片发光效率；其次在色转换层优化方面接着通过全无机二氧化硅包覆方式合成了高稳定性钙钛矿量子点色转换薄膜，且结合纤维素制备了纳米结构的高带宽钙钛矿量子点纸。通过结合高性能的激发芯片和色转换层，制备出宽色域、高稳定性、高调制带宽的Micro-LED全彩显示器件，推进Micro-LED全彩显示的规模化与多功能应用。