三维有序量子点的可控制备、结构表征与物性研究

The controllable preparation of uniform and ordered quantum dot array is a key precondition for quantum dot devices to reach their theoretically predicted performance. This project will study the effective control on preparation of uniform and ordered quantum dots by combination of patterned substrate made by electrochemical preparation and self-assembly technology. Based on InGaAs/GaAs material system, this project will study the preparation of uniform and ordered GaAs patterned substrate, the two dimensional positioning and growth of quantum dots, the uniform and ordered growth of three dimensional multilayer quantum dots, the characterization of relative morphology, structure and optoelectronic properties. This project will be able to obtain the preparation technology for uniform and ordered quantum dots, and realize the uniformity of the size, shape and the order of the distribution of quantum dots. Also, by the structure characterization and study on physical properties, one can find the relevance between the optoelectronic properties and geometrical structure characteristics so that to solve the thermodynamic and growth kinetics problems that involved in the growth of quantum dots.

均匀有序量子点阵列材料的可控制备是量子点器件的性能达到理论水平的一个关键前提条件。本课题将采用全新的电化学法制备图形化衬底，结合自组装生长技术研究如何有效地控制均匀有序量子点材料的制备。基于InGaAs/GaAs材料体系，研究均匀有序图形化GaAs衬底的制备、二维均匀量子点的定位生长、三维多层均匀有序量子点的生长、相关形貌结构以及光电特性的表征。通过本课题的研究可以探索均匀有序量子点阵列可靠的、可控的制备工艺，实现InGaAs量子点的尺寸、形状的高度均匀一致，空间分布的高度有序。此外，通过多层量子点的结构表征与相关物性研究，认识量子点的光电特性与三维量子点阵列的几何结构特征之间的关联性，解决量子点材料生长过程中所涉及到热力学与生长动力学问题。

制备均匀有序量子点材料对提高量子点器件的光电特性具有重要的意义。本项目通过结合制备图形化衬底技术与自组装生长技术完成了单层均匀有序量子点的可控制备研究以及多层均匀有序量子点的可控制备研究。系统的总结了均匀有序InGaAs量子点材料的可靠制备工艺条件，实现了InGaAs量子点在二维平面均匀分布。通过理论研究探明了基于非自由平坦表面量子点生长的分子动力学过程，量子点的选择性成核依赖于表面形貌与表面应变分布两个关键因素。经过我们对本项目的研究，为其他材料体系的均匀有序量子点的可控制备提供了一定的实验经验与理论支撑，为InGaAs量子点材料的进一步实际应用奠定了一定的基础。