Ching-Liang Dai This email address is being protected from spambots. You need JavaScript enabled to view it.1, Hsuan-Jung Peng1 , Mao-Chen Liu1 , Chyan-Chyi Wu2 and Lung-Jieh Yang3

1Department of Mechanical Engineering, National Chung Hsing University Taichung, Taiwan 402, R.O.C.
2Center for Measurement standards, Industrial Technology Research Institute, Hsinchu, Taiwan 300, R.O.C.
3Department of Mechnical and Electro-Mechanical Engineering, Tamkang University Tamsui, Taiwan 251, R.O.C.


Received: February 1, 2005
Accepted: April 15, 2005
Publication Date: September 1, 2005

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This work investigates the fabrication of a RF (ratio frequency) MEMS (micro elector mechanical system) switch using the standard 0.35 m 2P4M (double polysilicon four metal) CMOS (complementary metal oxide semiconductor) process and the post-process. The switch is a capacitive type, which is actuated by an electrostatic force. The structure of the switch consists of a CPW (coplanar waveguides) transmission lines and a suspended membrane. The CPW lines and the membrane are the metal layers of the CMOS process. The main advantage of the RF switch is only needed a simple post-process, which is compatible with the CMOS process. The post-process uses an etchant, silox vapox III, to etch oxide layer to release the suspended membrane and springs. Experiment results show that the pull-in voltage of the switch is about 17 V. The insertion loss and return loss in the range of 10 to 40 GHz are –2.5 dB and 13 dB, respectively.

Keywords: CMOS, Post-process, MEMS, RF Switch


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