宽禁带半导体纳米材料中束缚态激子的有效调控及其光电特性研究

The phenomenon of bound excitons is ubiquitous in semiconductor materials, and the proper utilization of bound excitons in wide bandgap semiconductor materials is one of the important ways to improve the performance of optoelectronic devices. However, the mechanism of how the bound excitons influence their photoelectric properties is not clear, which hinders their application for improving optoelectronic devices. In this project, the bound excitons in ZnO nano-materials will be chosen as the research object. First, we will establish the relationships between the bound states and the photoelectric properties of materials through theoretical research. Second,we will manipulate the bound states in the materials by experiment. Finally, the relationships between the specific binding states of the excitons and the photoelectric properties of ZnO nano-materials will be investigated by combining theorety and experiment. The purpose of this project is to study the effect of the introduction of bound excitons on the photoelectric properties in ZnO nano-materials, which lays the theoretical and experimental foundations for the regulation of bound excitons in experiment, and the improvement of the photoelectric performance of ZnO materials. The successful implementation of this project will promote the applied research of bound excitons in the semiconductor optoelectronic devices.

束缚态激子现象普遍存在于半导体材料中。宽禁带半导体纳米材料中束缚态激子的有效利用是提高光电器件性能的重要途径之一。然而，束缚态激子增强半导体材料的光电性能的机制还不是很清晰，这成为有效利用束缚态激子效应提高光电器件性能的主要瓶颈。本项目以宽禁带ZnO纳米材料中的束缚态激子为研究对象，通过理论研究得出束缚态与材料光电性能之间的联系；通过实验技术引入并控制材料中的束缚态；最终通过理论和实验相结合的方式对ZnO纳米结构中的特定束缚态激子和光电性能之间的联系进行基础研究。本项目旨在研究束缚态激子的引入对ZnO纳米材料光电性能影响的规律，为实验调控束缚态激子并用以提高ZnO材料光电性能奠定了理论和实验基础。本项目的成功实施还将推进束缚态激子在半导体光电子器件应用中的研究。

本项目开展了“宽禁带半导体纳米材料中束缚激子的有效调控及其光电特性研究”的工作，从束缚态荧光理论、ZnO纳米结构制备、束缚态引入技术和调控技术对ZnO纳米结构和光学性能的影响、ZnO纳米复合结构器件制备及光电性质研究四方面来实施。通过研究束缚态荧光理论，得出束缚态激子寿命、逃逸和复合速率与激子荧光特性的对应关系；采用化学气相沉积和水热法生长高质量ZnO纳米结构，研究了其发光特性；采用Ar+等离子体处理、化学水浴沉积法包覆ZnS纳米壳层实现对ZnO纳米线束缚态的引入；并利用不同Ar+等离子体处理时间和能量、不同热退火温度、不同覆盖度的ZnS纳米颗粒包覆的手段对束缚态典型荧光现象的改变，实现对束缚态的调控，优化技术参数；制备相应的束缚态依赖的光泵激光器和LED器件，并研究了ZnO纳米复合结构的探测器件，获得了光泵激光从无到有，紫外LED发光从无到有，器件性能增强了8倍的成果。本项目为束缚态实现高性能半导体光电器件的开发提供了思路和方法。