硅基光学相控阵扇形天线优化设计

Optimal design of silicon-based optical phased array sector antenna

在光学相控阵芯片中,天线单元的性能直接决定了波导中光波能量向外辐射的效率。在此基础上,主要针对扇形结构天线进行优化设计,通过对扇形天线增加浅刻蚀区域和硅薄带的设计,对天线向下衍射损失以及背反射损失进行了抑制,大幅提高了天线向上衍射效率。此外,分别对提高向上衍射效率和减小设计尺寸的设计要求制定了设计方案,对于高衍射效率方案,天线向上衍射效率达到81.6%,向下衍射减少到4%,背反射减少到1.4%;对于小型化方案,天线向上衍射效率达到67.2%,向下衍射减少到5.6%,背反射减少到1.2%,大幅提高了光学相控阵芯片集成度及发射效率。

In the optical phased array chip,the performance of the antenna unit directly determines the efficiency of the light wave energy in the waveguide to radiate outward.On this basis,the optimized design was mainly for the sector antenna.By adding a shallow etching area and a thin silicon strip to the sector antenna,the downward diffraction loss and back reflection loss of the antenna were suppressed,as well as the upward diffraction of the antenna was greatly improved.In addition,design schemes were formulated for the design requirements of improving the upward diffraction efficiency and reducing the design size.For the high diffraction efficiency scheme,the upward diffraction efficiency of the antenna reached 81.6%,the downward diffraction efficiency was reduced to 4%,and the back reflection was reduced to 1.4%.For the miniaturization scheme,the upward diffraction efficiency of the antenna was 67.2%,the downward diffraction was reduced to 5.6%,and the back reflection was reduced to 1.2%,which greatly improved the integration and emission efficiency of the optical phased array chip.