基于光频梳的大带宽高线性低电压硅基发射芯片关键技术研究

As the demand for low-cost large-capacity high-speed and high-linearity optical transmission in 5G Communication front-haul and the electron-optical integration in active phase array radar, the research on the key technologies of the large-bandwidth, high-linearity, low-voltage silicon transmitter chip based on optical frequency comb is carry out in this project. This technology include silicon optical frequency comb generator sub-technology, low-voltage and high-linearity modulation techniques for silicon MZI Coupled Racetrack ring structure, silicon wavelength division multiplexing sub-technology with low-voltage feedback compensation, silicon waveguide optical power detection and feedback algorithm. Benefit from the silicon photonics device, which can be fabricated in a mature CMOS process, silicon optoelectronic integrated devices can effectively reduce the cost of the chip. Through the research on the key technology, the carrier generation of each sub-channel in dense wavelength division multiplexing, the nonlinearity of silicon electro-optical modulation and the overall wavelength drift of the WDM channel due to process tolerance can be solved, and the voltage is effectively reduced , operation stability is improved. During the research, the performance of the chip is optimized by link simulation, device 3D modeling and simulation, and process simulation. Though twice tape-out and test the packaged device, the implementation of key technologies is verified.

针对5G通信前传和有源相控阵雷达电光集成中对低成本化的大容量高速高线性光传输的需求，本项目开展基于光频梳的大带宽高线性低电压的硅基发射芯片关键技术研究。该关键技术包括硅基光频梳产生子技术、硅基MZI Coupled Racetrack ring结构的低电压和高线性调制子技术、具有低电压反馈补偿的硅基波分复用子技术和硅波导光功率检测与反馈算法。得益于硅光子器件可利用成熟的CMOS工艺制备，硅基光电子集成器件可有效降低芯片成本。通过关键技术的研究，可解决如下问题：密集波分复用中各个子通道的载波产生，硅基电光调制存在的非线性和因工艺容差造成的波分通道整体波长漂移；并有效降低电压，提高工作稳定性。在研究过程中通过链路仿真，器件三维建模仿真，工艺仿真来优化芯片的性能。通过两次芯片流片并对封装后的器件进行测试来验证关键技术的实现。

本课题的项目背景：在军事装备研制中，新一代二维有源相控阵雷达中光传输所占比例将进一步扩大，将接收信号通过光发射芯片调制到光链路上送往后端进行信号处理，来解决高频长距条件下电传输的损耗和电磁干扰等问题。本课题的研究内容包括探索硅基光频梳产生子技术、硅基波导阵列结构的低电压和高线性调制子技术、具有低电压反馈补偿的硅基波分复用子技术和硅波导光功率检测与反馈算法。得益于硅光子器件可利用成熟的CMOS工艺制备，制备了硅基波分复用芯片和光相控阵芯片，研制面向航天的光发射模块。重要结果：解决硅基MZI结构密集波分复技术，光波导相控阵列技术，航天条件下的光模块制备，实现通道隔离度大于20dB，波束扫描范围-25°到25°。科学意义：表明硅基发射芯片可以应用于航天载荷中，未以后硅基集成芯片在卫星、空间站的应用打下基础。