Title :
RF MEMS membrane switches on GaAs substrates for X-band applications
Author :
Zheng, Wei-Bin ; Huang, Qing-An ; Liao, Xiao-Ping ; Li, Fu-Xiao
Author_Institution :
Key Lab. of MEMS of Minist. of Educ., Southeast Univ., Nanjing, China
fDate :
6/1/2005 12:00:00 AM
Abstract :
Micromechanical switches have demonstrated great potential at microwave frequencies. For low-loss applications at microwave frequencies, it is important to use high-resistivity substrates. This paper presents the design and fabrication of the shunt-capacitive MEMS switch on GaAs substrates. Analytical mechanical and impedance models of the membrane switch are given, and the results are confirmed by using the ANSYS and HFSS software, respectively. A surface micromachining process, which is compatible with the conventional millimeter-wave integrated circuits (MMICs) fabrication technology, was adopted to fabricate the RF switch on GaAs substrates. Its S-parameter was taken using a HP8510C vector network analyzer and a Cascade Probe station. The measured insertion loss of the switch and its associated transmission line is less than 0.25 dB from 1 to 25.6 GHz, and the isolation may reach -42 dB at its self-resonate frequency of 24.5 GHz. The actuation voltage is about 17 V. The switch has demonstrated lifetimes as long as 5×106 cycles. The wideband high performance in isolation and insertion loss offers the monolithic integration capability with GaAs MMICs.
Keywords :
III-V semiconductors; MMIC; gallium arsenide; micromachining; microswitches; microwave switches; 0.25 dB; 1 to 25.6 GHz; ANSYS software; Cascade Probe station; GaAs; HFSS software; HP8510C vector network analyzer; RF MEMS membrane switches; S-parameter; X-band applications; high-resistivity substrates; insertion loss; micromechanical switches; millimeter-wave integrated circuits fabrication technology; surface micromachining process; transmission line; Application software; Biomembranes; Fabrication; Gallium arsenide; Insertion loss; MMICs; Micromechanical devices; Microwave frequencies; Radiofrequency microelectromechanical systems; Switches; GaAs; microelectromechanical systems (MEMS); millimeter-wave integrated circuits (MMICs); switch;
Journal_Title :
Microelectromechanical Systems, Journal of
DOI :
10.1109/JMEMS.2005.844846