锗硅/硅异质结电光调制器的研究

Conventional electrical interconnection is facing transmission bottlenecks in integrated circuits, electrical interconnection is replaced by optical interconnection, that will be a major trend in the future. High-speed large-scale optical integrated circuit requires high-speed low-power electro-optic modulator with optical signal. The carrier concentration and reverse extraction time of the waveguide region is a pair of unsolvable contradictions in the traditional silicon electro-optic modulator. This project intends to combine the many advantages of silicon-germanium materials with the high refractive index, high mobility, and so on, and design a new structure of the SiGe/Si heterostructure electro-optic modulator. It has a relatively simple process and excellent features, by solving the contradictions of carrier concentration and reverse extraction time of the waveguide region in electro-optic modulator, the excellent characteristics of electro-optic modulator with high-speed and low power consumption can be got, and the performance indicators are superior to conventional silicon electro-optic modulator. Based on researching on SiGe/Si heterojunction theory of electro-optic modulator deeply, a simple and reliable process and implementing scheme are designed. The researching success of this project will greatly improve the speed of the electro-optic modulator, reducing its power consumption, improving the frequency and power of the optical integrated circuits, being favorable to the miniaturization and integration of optical integrated circuits, so that electrical integration circuit is replaced by the optical integrated circuits early, which is also important to alleviate the energy crisis.

集成电路中传统的电互连正面临传输的瓶颈，以光互连代替电互连将是今后的一大发展趋势。高速大规模光集成电路要求电光调制器对光信号具有高速、低功耗的处理能力。传统硅电光调制器中波导区载流子浓度与反向抽取时间是一对不可解决的矛盾。本项目拟结合锗硅材料自身的高折射率、高迁移率等众多优点，设计出一种新型结构的锗硅/硅异质结电光调制器。它的工艺相对简单，特性优良，通过解决电光调制器中波导区载流子浓度与反向抽取时间的矛盾，可以获得高速、低功耗的优良特性，使其各项性能指标均优于常规的硅电光调制器。对锗硅/硅异质结电光调制器的理论进行深入研究，设计出简便易行可靠的工艺流程和实施方案。该项目研究成功将大大提高电光调制器的速度，降低其功耗，改善光集成电路的频率和功耗，有利于光集成电路的小型化和集成化，从而使光集成电路能早日替代电集成电路，对缓解能源危机也具有重要意义。

本项目结合锗硅材料自身的高迁移率等众多优点，设计了一种新型锗硅/硅异质结微环电光调制器，并针对锗硅/硅异质结的注入效率进行研究。通过大量仿真实验，建立了新型锗硅/硅异质结微环电光调制器的PIN电学调制模型，优化了模型参数；通过SiGe/Si异质结理论的分析，得到了Si/SiGe/Si异质结能带，给出了能带中势垒高度的定量分析公式，并且通过软件仿真验证了能带分析的正确性；使用器件模拟软件，仿真了掺杂浓度、结构参数、以及Ge含量对调制区载流子浓度的影响，有效提高了电光调制器的注入效率。相同调制效果下，新型锗硅/硅异质结微环电光调制器的反向抽取时间缩短了11.8%，调制电压（功耗）降低了23.3%，有效缓解了电光调制器中调制区载流子浓度与反向抽取时间的矛盾；根据模拟优化结构，制定了新型锗硅微环电光调制器的工艺流程，制作了锗硅/硅异质结微环电光调制器。