硅基单片集成单边带调制器

Monolithic Integrated Silicon Single Sideband Modulator

基于CMOS兼容的硅基光子集成工艺,设计并实现了一种具有高边带抑制比的硅基单片集成单边带调制器。单边带调制器采用正交混合耦合器实现上下两臂等幅度、90°相位差的射频信号加载,基于硅基双驱动马赫曾德尔调制器的热移相器调控上下两臂光相位差为90°,实现了效果显著的单边带抑制。基于CUMEC公司CSiP180 Al工艺和工艺设计包(PDK)完成芯片制备,采用金丝引线实现了正交混合耦合器的空气桥结构。测试结果显示该硅基单片集成单边带调制器在18~32 GHz频率内边带抑制比均高于12 dB,在21 GHz工作频率时边带抑制比达到了32 dB。该单边带调制器有望应用在光通信和微波光子系统中。

A monolithic integrated silicon single sideband modulator with high sideband rejection ratio was designed and fabricated based on CMOS-compatible silicon photonics integration process.The quadrature hybrid coupler was implemented in the single sideband modulator to realize the loading of radio frequency signals on the upper and lower arms with equal amplitude and 90°phase difference.The optical phase difference between the upper and lower arms was adjusted to 90°by the thermal phase shifter based on the dual-drive silicon Mach-Zehnder modulator,which achieves significant single sideband rejection.The chip was fabricated based on the CSiP180 Al process and process design kit(PDK)of CUMEC company,and the wire bonding was utilized to realize the air bridge in the quadrature hybrid coupler.The experimental results show that the sideband rejection ratio of the fabricated monolithic integrated silicon single sideband modulator exceeds 12 dB from 18 GHz to 32 GHz and reaches 32 dB at 21 GHz.The single sideband modulator is expected to be applied in the optical communication and microwave photonics system.