摘要
由于Si基光发射材料具有与先进的Si微电子技术兼容和成本低廉的优势 ,一直是光电子集成 (OEIC)工程应用的首选材料。但由于体材料Si是一种间接带隙半导体 ,不可能成为有效的光发射体。如何通过已有的物理学原理和可行的微加工技术把它改造成为有效的发光材料 ,甚至成为严格意义上的直接带隙材料 ,给实验研究工作者和材料设计理论工作者提出了挑战。除多孔Si之外 ,最近已有若干令人鼓舞的方案 ,包括Si纳米晶、Si/O超晶格和注硼位错工程等方法 ,实现了Si基材料的有效发光试验。本文在分析其中最令人关注的进展的基础上 ,认为要实现高效率、高响应速率的Si基发光材料 ,以适应超高速、大容量信息处理和传输的要求 ,较好的途径是直接设计出具有直接带隙的Si基材料。因为避免界面态参与发光过程 ,对于提高响应速度至关重要。但是如何设计直接带隙的半导体材料并没有现成的规则可依循。我们建议一个经验的对称性法则 ,并设计出一种新的硅基超晶格。通过计算机模拟计算表明 ,其中Se/Si10 /Se/Si10 /Se超晶格具有相当理想的直接带隙特征 ,其带隙处于红外波段。预期这类新材料及有关器件会有优越的光发射和各种光学性能 ,其制作也可方便地与硅微电子工艺兼容。因此 。
The silicon based optical emitting materials are always the first candidate materials for the optoelectronic IC (OEIC) and its engineering applications, due to its low cost and the excellent compatibility with the advanced Si technology in microelectronics. However, the crystalline bulk silicon is an indirect electronic bandgap semiconductor with very poor light emission efficiency. It has been considered unsuitable for optoelectronic applications. A great challenge to experimenters and theorists is that how to make or design an efficient Si based light emission material using an advanced technology and physics principles. In recent, several schemes, except porous silicon, have been suggested which include the silicon nanocrystals, c Si/O superlattices (SLs) and dislocation engineering. The light emission efficiency has been improved greatly in these Si based systems. Based on the review of these new achievements, design a Si based material with direct bandgap is considered a more direct solution. Because of the interface states in Si based devices have a slow response rate in optical processes . Avoiding interface states are very important for the high speed optical devices and its applications. However, one does not know any critical rule for designing the newly Si based materials with a direct band gap until now. In this paper we suggest an empirical symmetry rule and design a series of Si based superlattices. The computer simulations indicate that one of these superlattices, Se/Si 10 /Se/Si 10 /Se, is a semiconductor with a direct gap character and its band gap lie in the infrared range, perhaps, to be lie in the window of minimal absorption in current optical fibers. It is expected that the materials and its devices have the excellent abilities for light emission and other optical properties . In addition, this material is easily compatible with Si microelectronics technologies. Therefore, the material produced from computational design may be having potential applications in the field of the optoelectronics .
出处
《发光学报》
EI
CAS
CSCD
北大核心
2002年第5期419-424,共6页
Chinese Journal of Luminescence
基金
国家自然科学基金重大项目 (698962 60 )
信息部项目 (60 0 770 2 9)资助项目
