Basic Concepts of Moving-Sidewall Tuneable Capacitors for RF MEMS Reconfigurable Filters
2011 (English)In: 6th European Microwave Integrated Circuits (EuMIC) Conference, The European Microwave Association , 2011, 526-529 p.Conference paper (Refereed)
This paper presents for the first time MEMS tuneablefilters, where the reconfiguration of the filter is achieved bymoving the sidewalls of a 3D micromachined transmission line.The sidewalls of the transmission line are moved by MEMSelectrostatic actuators completely integrated into the groundlayers of a thick-film coplanar waveguide. Multi-step actuatorshave been utilized for achieving a tuning range of up to 2.41 forthe tuneable capacitance elements. Two different 3Dtransmission line metallization schemes and two differentconcepts for tuning the capacitive load have been investigatedfor constructing filters based on this novel tuning mechanism.Measurements of fabricated devices have revealed that 3Dtransmission lines with top metallization only, and capacitorsavoiding the routing of the RF signal over mechanical-springmeanders achieve the best results. A successfully implementedfilter based on this configuration is shown, with a passbandinsertion and return loss of 5 and 12 dB, respectively, at a centerfrequency of 20 GHz. Various MEMS actuators designs withspring constants from 3.5 to 95 N/m have been implemented,resulting in actuation voltages of 15.4 to 73 V. The self-actuationpower simulated in a non-linear Agilent Advanced DesignSystem model has been estimated to 40 and 50 dBm for the softand the stiff spring actuators, respectively. The fabrication isdone by a single-mask silicon-on-insulator RF MEMS process.
Place, publisher, year, edition, pages
The European Microwave Association , 2011. 526-529 p.
RF MEMS, tuneable filters, micromachined transmission lines
Other Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-50164ScopusID: 2-s2.0-84855809863OAI: oai:DiVA.org:kth-50164DiVA: diva2:461175
6th European Microwave Integrated Circuits (EuMIC) Conference
QC 201112132011-12-132011-12-022011-12-13Bibliographically approved