多孔耦合型太赫兹波导定向耦合器的设计

发布时间：2018-03-02 01:19

本文关键词： 定向耦合器太赫兹波导 MEMS　出处：《红外与激光工程》2017年01期 　论文类型：期刊论文

【摘要】：设计了一种结构紧凑、工作频带较宽、耦合平稳、高方向性的"十字形"多孔耦合的太赫兹波导定向耦合器。基于多孔耦合原理,利用HFSS软件对太赫兹波导定向耦合器进行了模型仿真和结构优化。仿真结果表明:在325~475 GHz带宽范围内,该多孔耦合太赫兹波导定向耦合器耦合度达到7.5±0.8 d B,隔离度达到30 d B,即方向性优于20 d B,各端口回波损耗小于-20 d B。通过对该波导定向耦合器进行高温高压模拟仿真,确定了使用负性光刻胶SU-8作为结构材料的可行性,提出应用MEMS工艺在硅衬底上进行加工,将牺牲层工艺应用到波导腔结构的制作中。利用光刻在直通波导和耦合波导公共宽壁上形成的"十字形"等间距排列耦合孔结构,可以实现较宽的带宽和良好的耦合平坦度。该方法提高了耦合孔尺寸和位置的精度,减小了反射损耗,为太赫兹波导结构的加工提供了新思路。
[Abstract]:In this paper, a "cross-shaped" porous coupling THz waveguide directional coupler with compact structure, wide working band, steady coupling and high directivity is designed. Based on the principle of porous coupling, The model simulation and structure optimization of THz waveguide directional coupler are carried out by using HFSS software. The simulation results show that the bandwidth of THz waveguide directional coupler is in the range of 325 ~ 475 GHz. The coupling degree of the porous coupling THz waveguide directional coupler is 7.5 卤0.8 dB, the isolation degree is 30 dB, that is, the directivity is better than 20 dB, and the return loss of each port is less than -20 dB. The high temperature and high pressure simulation of the waveguide directional coupler is carried out. The feasibility of using negative photoresist SU-8 as structural material is determined. MEMS process is proposed to process on silicon substrate. The sacrificial layer technology is applied to the fabrication of waveguide cavity structure. The "cross" equidistant coupled hole structure formed by photolithography on the common wide wall of the straight through waveguide and the coupling waveguide is used. This method improves the accuracy of the size and position of the coupling holes and reduces the reflection loss. It provides a new way for the fabrication of terahertz waveguide structures.
【作者单位】：中北大学电子测试技术重点实验室;仪器科学与动态测试教育部重点实验室;
【基金】：国家自然科学基金(61401405,51475438) 山西省基础研究项目(2014011021-4)
【分类号】：TN622

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