| Around 10 year ago, a lot of attention started to be drawn to the research of MEMS switches. Even since then, RF MEMS switch has found its great application in the area of wireless communications due to its small size, light weight, low power consumption and high isolation. However, there are not many articles which have thoroughly introduced simulation, design and fabrication process of the switches from all those references. This dissertation focuses on the design and fabrication of RF MEMS contact switches. The main contributions are as follows:A method of combining the layout design software with 3D finite element analysis (FEA) software is presented which can solve the problem of drawing 3D complicated models in analysis software.The switch mechanical characteristics are compared by using ANSYS. The real switch models are simulated after the problem of the mass data induced by complicated models is solved. The model frequencies of different length bridges and three switches with different hinge shapes are simulated. The switch with the least spring constant is found as well. The switch electrical characteristics from 1-10GHz are also simulated using HFSS.The fabrication process is designed using surface silicon fabrication technologies. Many experiments on the sacrificial layer including spinning and etching are explored. The suitable temperature and etching conditions are found. Observations and researches are done to find the problems in layout design and fabrication process. The improvement focuses on decreasing the actuation voltage and improving reliability.Two layouts are drawn and the prototype of the first layout is fabricated. Testing and measurement results show that the switch's actuation voltage is about 28V, and the best life time is 700,000 cycles. The typical shunt switch is capable of proving less than 0.5dB insertion loss and 35dB ~ 45dB isolation in the frequency range 1 ~ 10GHz. The series switch provides 0.5dB ~ 1.5dB insertion loss and 40dB ~ 70dB isolation.
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