硅基深紫外AlGaN量子点的MBE可控生长及超材料光学特性的研究

Deep-ultraviolet AlGaN light-emitting devices have the advantages of innocuity, environmental protection, low power consumption, long working life and small volume, etc. Therefore, they have broad application prospects in the fields of the sterilization and confidential communication, etc. However, due to the relatively low light extraction efficiency (LEE) and internal quantum efficiency (IQE), the development and applications of deep-ultraviolet light-emitting devices have been seriously limited. ..According to the above scientific problems, this project designs and modulates the structures and distributions of AlGaN quantum dots (QDs) by the technology of molecular beam epitaxy (MBE). By enhancing the metamaterial optical characteristics of QD arrays, as well as the transmissivity in deep-ultraviolet range, the LEE is able to be increased. Furthermore, by inserting the superlattice structure into QDs, as well as modulating the superlattice structure, the project can further enhance the quantum confinement effects on carriers, which could result in the enhanced IQE. Combined with numerical simulations, the project explores the intrinsic correlations between the modulations of the AlGaN QD structures and distributions (including QDs with embedded superlattices), and the modulations of LEE and IQE in detail. By studying the intrinsic physical mechanisms, the corresponding theoretical models can be established. The successful development of the project will provide the reliable theoretical basis and technical support for the wide applications of deep-ultraviolet light-emitting devices in the future.

深紫外AlGaN发光器件具有无毒、环保、耗电低、使用寿命长和体积小等优点，在杀菌消毒和保密通讯等领域具有广阔的应用前景。然而，较低的光提取效率与内量子效率，严重制约了深紫外发光器件的发展与应用。. 本项目针对上述科学难题，基于分子束外延生长（MBE）技术，设计并调控AlGaN量子点的结构与分布，增强量子点阵列的超材料光学特性，通过提高深紫外光的透射率，进而提高光提取效率；通过在量子点中内嵌并调控超晶格结构，进一步增强其对载流子的量子限制效应，以提高内量子效率；结合数值仿真，深入探索调控AlGaN量子点（包含内嵌超晶格的量子点）的结构、分布与调控光提取效率及内量子效率的内在关联，并研究其物理机理，建立相应的理论模型。此项目的顺利开展，必将为未来深紫外发光器件的广泛应用提供可靠的理论依据和技术支持。

深紫外AlGaN光电器件具有无毒、环保、耗电低、使用寿命长和体积小等优点，在保密通讯等领域具有广阔的应用前景。然而，一些关键问题严重制约了包括深紫外探测器在内的深紫外光电器件的发展与应用。. 目前，项目研究内容已基本完成，包括: 1）初步建立含AlGaN量子点的纳米柱光学模型，分析了光学特性；2）掌握制备纳米柱阵列的关键技术，初步实现了选择性生长；3）实现内嵌超晶格的纳米柱制备，单层厚度的精度达到1nm；4）初步掌握了关键外延参数与纳米柱结构调控的内在关联；5）制备了含深紫外AlGaN量子点的纳米柱阵列，波长达到271nm，Al含量超过50%。. 同时，本项目超额完成了一些新内容，包括：1）基于含AlGaN量子点的纳米柱阵列研发了无填充物的器件制备工艺，并成功制备深紫外探测器；2）发明了一种成本低的剥离技术，高效制备超柔性透明的GaN基纳米柱薄膜；3）成功制备了可360°探测的透明探测器，突破了紫外/可见光抑制比的瓶颈。. 本项目的论文、专利和人才培养成果均超过预期。项目实施期内，负责人作为第一/通讯作者在ACS Photonics等知名期刊上发表SCI论文11篇，申请中国发明专利5项，授权实用新型专利1项，并申请了美国、日本和德国专利；负责人在学术会议上做口头报告2次，海报1次。另一方面，直接参与本项目研发的4名博士生均顺利毕业，负责人获评副研究员和中科院苏州纳米所优秀青年，并连续两年获得本单位“青年学术奖”。. 综上所述，本项目成果突出，柔性/透明的光电器件在未来有望可以广泛应用于智能电子皮肤、汽车玻璃导航等前沿领域，有巨大的发展和应用潜力，也可为新型GaN基光电器件的发展提供技术支持。