Research On High Performance Terahertz Filter

In the electromagnetic spectrum, terahertz waves have special characteristics because of its special position, which makes terahertz technology had great scientific significance and broad application prospects in many aspects. Terahertz technology has been grown up to be a hot topic research. Terahertz filter controls the frequency response of the entire system, which plays a key role in the electric circuit. As an important part of the terahertz system, the high-performance design and implementation have to be a very positive and important significance.The high-performance terahertz filter is produced under the current design and processing technology level. Firstly, this thesis introduces the definition of the terahertz wave and reviews the history of the terahertz filter. This article also briefly describes the status of the MEMS technology. Secondly, based on the basic theory of resonant cavity, this thesis explores a variety of solutions to achieve high performance THz waveguide filter in the same frequency band. This thesis successfully produced a high-performance THz waveguide filter according to the advanced MEMS technology in China. Finally, according to the basic theory of filter and actuator, this thesis completed the design of the double-curved heat actuator and its layout.This thesis completed the initial value of the simulation and optimization settings of the tunable waveguide filter which works in the G band. The main research work and results can be summarized as follows:Firstly, according to the deep reactive ion etching(DRIE) technology based on the silicon substrate, this thesis successfully designed and produced some terahertz waveguide filters whose operating frequency are higher than 0.6THz. Moreover, a novel structure of waveguide filter with circular cavities is proposed. Two THz waveguide bandpass filters based on micro-electro-mechanical technology are designed and fabricated. At the same time, this thesis also designed and fabricated a dual-mode filter with a superior performance. The test results show that the filters have low insertion loss(less than 3dB) and good band rejection(more than 20dB@10% of the center frequency).Secondly, based on the PolyMUMPs(three-layer polysilicon surface micromachining process) process, this thesis completed the simulation and optimization of the double-curved heat actuators and fitted it to the E-plane waveguide filter. We found that the height of the actuator can influence the center frequency of the E-plane waveguide filter through the simulation.In this thesis, some high-performance terahertz filter elements are successfully designed and fabricated, which have great practical value for the research and development of THz systems.