Conference paper
Low Voltage, High-Q SOI MEMS Varactors for RF Applications
A micro electromechanical tunable capacitor with a low control voltage, a wide tuning range and high electrical quality factor is presented with detailed characterizations. A 50μm thick single-crystalline silicon layer was etched using deep reactive ion etching (DRIE) for obtaining high-aspect ratio (>20) parallel comb-drive structures with vertical sidewalls.
Consisting of only one lithographic mask step, the process sequence can be completed in a short time. Having 1 pF of nominal capacitance, the device offers an electrical quality factor of 100 at 100MHz and a self resonance at 4.08 GHz, enabling the usage as a passive component in the RF band. The mechanical settling time of the varactor is measured to be 200 μs in ambient air.
For control voltages ranging from 1.5V to 5V, tuning ratios of 2:1, 1.7:1 and 1.5:1 are obtained from different capacitor designs. It was found that the device is a suitable passive component to be used in band-pass filtering, voltage controlled oscillator or impedance matching applications on the very high frequency(VHF) and ultra high frequency (UHF) bands.
| Language: | English |
|---|---|
| Publisher: | IEEE |
| Year: | 2003 |
| Pages: | 607,608,609,610 |
| Proceedings: | 29th European Solid-State Circuits Conference |
| ISBN: | 0780379950 and 9780780379954 |
| Types: | Conference paper |
| DOI: | 10.1109/ESSCIRC.2003.1257208 |
| ORCIDs: | Hansen, Ole |
1.5 to 5 V 100 MHz 4.08 GHz 50 micron Capacitors Etching Low voltage Micromechanical devices Q factor RF applications Radio frequency SOI MEMS varactors Silicon Tuning UHF band VHF band Varactors Voltage control band-pass filtering band-pass filters capacitance deep reactive ion etching high electrical quality factor impedance matching impedance matching applications lithographic mask step low control voltage micro electromechanical tunable capacitor micromechanical devices nominal capacitance parallel comb-drive structures process sequence silicon-on-insulator sputter etching thick single-crystalline silicon layer varactors voltage controlled oscillator voltage-controlled oscillators wide tuning range
