Understanding the Luminescence Efficiency of Silicon Quantum Dots

了解硅量子点的发光效率

• 批准号: 282295808
• 负责人: Professorin Dr. Margit Zacharias
• 金额: --
• 依托单位: Matematicko-fyzikální fakulta
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2016
• 资助国家: 德国
• 起止时间: 2015-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/282295808?language=en
• 关键词: Understanding; Luminescence; Efficiency; Silicon; Quantum

Significant part of the optical properties of Si QDs is either still under controversial debate or completely unknown or was out of experimental reach up to now. This cooperation project aims to clarify several important properties that are required to obtain a comprehensive picture of the physical mechanisms and limits of the optical performance of 0 dimensional silicon nanostructures. The motivation for this study is two-fold: On the one hand, fundamental semiconductor science will benefit in general from a comprehensive understanding of the size effects in indirect quantum dots such as Silicon that occur when the dimensions are reduced below the exciton Bohr radius. However, apart from this well justified academic interest, silicon represents the technologically most important and virtually omnipresent semiconductor. The aggressive down-scaling of microelectronics industry is progressively reducing the active silicon volumes into a size range where quantum confinement effects start to play a major role. Hence, extensive knowledge is mandatory including the cross-talking of such adjacent quantum dots. For free standing Si QDs the light emission efficiency of Si QDs can easily reach 25% and even ~50% were reported. Compared to the bulk Si quantum yield of 10-5 the reduction of the dimensions to 5 nm opens a gate into a completely new world of applications. Currently, silicon optoelectronics is able to modify, guide, switch and detect light but it is not able to efficiently generate light from electricity. However, the light sources in optoelectronics are often made of III-V semiconductors which cannot be integrated on the material level into microelectronic circuits (Si is a dopant for many III-V materials and those are mostly mid-gap defect states in Si). Realistically, there is still a long way to go until e.g. optical on-chip communication can be solely fabricated from Si-based materials. But it can be taken for granted that Si nanostructures will be the pivotal point of this technology evolution. Therefore, intense research on fundamental optical properties and the principal limits of the optical performance of Si quantum dots is important. In detail the following objectives will be investigated in details: (1) Absorption Cross Section (ACS) of Si QDs, (2) Quantum Yield of Si QDs, and (3) Interaction of the Dielectric Matrix with Si QDs.

到目前为止，硅量子点的光学性质的重要部分仍然处于有争议的争论中，或者完全未知，或者是实验无法达到的。该合作项目旨在阐明获得0维硅纳米结构光学性能的物理机制和限制的全面图片所需的几个重要特性。这项研究的动机是双重的：一方面，基础半导体科学将从全面理解间接量子点（如硅）的尺寸效应中受益，当尺寸减小到激子玻尔半径以下时会发生这种效应。然而，除了这种合理的学术兴趣，硅代表了技术上最重要的和几乎无处不在的半导体。微电子工业的积极缩小规模正在逐步将有源硅体积减小到量子限制效应开始发挥主要作用的尺寸范围内。因此，广泛的知识是强制性的，包括这种相邻量子点的串扰。对于自支撑的Si QD，Si QD的发光效率可以容易地达到25%，甚至~50%。与10-5的体硅量子产率相比，尺寸减小到5 nm打开了一扇通往全新应用世界的大门。目前，硅光电子学能够修改，引导，切换和检测光，但它不能有效地从电力中产生光。然而，光电子学中的光源通常由III-V族半导体制成，其不能在材料水平上集成到微电子电路中（Si是许多III-V族材料的掺杂剂，并且这些材料主要是Si中的中间带隙缺陷态）。实际上，还有很长的路要走，直到例如光片上通信可以单独由Si基材料制造。但可以肯定的是，硅纳米结构将是这一技术发展的关键点。因此，深入研究硅量子点的基本光学性质和限制其光学性能的主要因素是非常重要的。具体而言，将详细研究以下目标：（1）Si量子点的吸收截面（ACS），（2）Si量子点的量子产率，以及（3）介电基质与Si量子点的相互作用。