volume | PIER Journals

2006-09-15

Two Novel Structures for Tunable MEMS Capacitor with RF Applications

Ebrahim Abbaspour-Sani,

Dr. Ebrahim Abbaspour-Sani

Urmia University

IRAN

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N. Nasirzadeh,

Dr. N. Nasirzadeh

Urmia University

Iran

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Gholamreza R. Dadashzadeh

Dr. Gholamreza R. Dadashzadeh

Shahed University

Iran

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, Vol. 68, 169-183, 2007

doi:10.2528/PIER06081404

Abstract

Two novel structures for high-Q MEMS tumble capacitors are presented. The proposed designs include full plate as well as the comb structured capacitors. They can be fabricated employing surface micromachining technology which is CMOS-compatible. The structures do not require the cantilever beams which introduce considerable series resistance to the capacitor and decrease the quality factor. Therefore, our proposed structures achieve better Q in a smaller die area. The simulated results for 1 pF full plate capacitor shows a tuning range of 42% and a Q of 47 at 1 GHz. However, with the same initial capacitance, but the comb structure, the tuning range is increased to 43% but the Q is decreased to 45 at 1 GHz. The simulated Pull-in voltage with no residual stress is 3.5 V for both capacitors. The S11 responses are reported for a frequency range from 1 up to 4 GHz.

Citation

Ebrahim Abbaspour-Sani N. Nasirzadeh Gholamreza R. Dadashzadeh , "Two Novel Structures for Tunable MEMS Capacitor with RF Applications," , Vol. 68, 169-183, 2007.
doi:10.2528/PIER06081404
http://www.jpier.org/PIER/pier.php?paper=06081404

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