表面等离激元修饰的ZnO核壳量子点发光特性及其短波长LED研究

量子点发光二极管（QLED）具有高光效、可调谐、颜色纯等优点，是未来极具潜力的发光技术，是当前发光器件领域内的研究热点。目前，高性能紫外波段QLED的研发是该领域的难点和亟待突破的方向。ZnO是继GaN之后一种重要的第三代半导体材料。本项目拟开展基于ZnO核壳量子点的短波长QLED研究：提出将单晶ZnO量子点、核壳量子阱、表面等离激元（SP）三位一体地引入到QLED中这一结构设计新思路；在器件中插入超薄非晶氧化物电子阻滞层，平衡电子和空穴在迁移率上的差异，促进载流子在ZnO量子点层辐射复合；利用低损耗、宽带可调的金属SP或新型碳基SP与ZnO量子点进行共振耦合，进一步提升ZnO基QLED的紫外发光性能。本项目聚焦短波长QLED的应用需求，提出了发展ZnO基高效紫外光QLED的新方案，并为研发基于其它宽禁带材料的发光器件提供参考，是物理、信息和光电子学交叉领域的前沿课题。

Quantum dot light-emitting diode (QLED), as a new and promising luminescence technology in the future, is a research hot spot in the field of modern light emitters, owing to their high fluorescence efficiency, tunable luminescence wavelength and pure light-emitting color. So far, the research and development of high-performance semiconductor QLEDs with UV light emission have always been a difficult challenge. ZnO was recognized as one of the most important wide-band-gap semiconductor materials after the success of GaN. This proposal aims to explore and develop QLEDs with high-efficiency short-wavelength emission based on ZnO core/shell structured quantum dots (QDs). In this project, a new QLED device structure is proposed, in which single-crystalline ZnO QDs as active emission layer, core/shell quantum-well energy band alignment and surface plasmons (SPs) have been synergistically introduced. To compensate the mobility difference between electron and hole, an ultrathin amorphous oxide film, serving as electron retarding/blocking layer, is properly inserted into the QLED device structure, which facilitates effective radiative recombination of injected electrons and holes within the ZnO QDs active region. Furthermore, metal-based or carbon-based SPs with low joule dissipation and wide spectral resonance range, are also employed for enhancing the UV electroluminescence performance of these ZnO core/shell structured QLEDs, by means of the resonance coupling effect between SPs and excitons. This proposal focuses on the application demand of short-wavelength QLEDs, and suggests a novel plan for developing ZnO-based high-efficiency UV QLEDs. The research findings of this project may provide scientific and technical references for developing light-emitting devices based on other wide-band-gap semiconductors. All in all, this proposal is a cutting-edge research project in multidiscipline fields such as physics, information science and optoelectronics.