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.
|Title of host publication||Proceedings of the 29th EuropeanSolid-State Circuits Conference (ESSCIRC)|
|Publication status||Published - 2003|
|Event||Proceedings of the 29th European Solid-State Circuits Conference, 2003. ESSCIRC '03. - |
Duration: 1 Jan 2003 → …
|Conference||Proceedings of the 29th European Solid-State Circuits Conference, 2003. ESSCIRC '03.|
|Period||01/01/2003 → …|