Basic concepts of moving-sidewall tuneable capacitors for RF MEMS reconfigurable filters
2011 (English)In: Eur. Microw. Week: "Wave Future", EuMW, Conf. Proc. - Eur. Microw. Conf., EuMC, 2011, 1087-1090 p.Conference paper (Refereed)
This paper presents for the first time MEMS tuneable filters, where the reconfiguration of the filter is achieved by moving the sidewalls of a 3D micromachined transmission line. The sidewalls of the transmission line are moved by MEMS electrostatic actuators completely integrated into the ground layers of a thick-film coplanar waveguide. Multi-step actuators have been utilized for achieving a tuning range of up to 2.41 for the tuneable capacitance elements. Two different 3D transmission line metallization schemes and two different concepts for tuning the capacitive load have been investigated for constructing filters based on this novel tuning mechanism. Measurements of fabricated devices have revealed that 3D transmission lines with top metallization only, and capacitors avoiding the routing of the RF signal over mechanical-spring meanders achieve the best results. A successfully implemented filter based on this configuration is shown, with a passband insertion and return loss of 5 and 12 dB, respectively, at a center frequency of 20 GHz. Various MEMS actuators designs with spring constants from 3.5 to 95 N/m have been implemented, resulting in actuation voltages of 15.4 to 73 V. The self-actuation power simulated in a non-linear Agilent Advanced Design System model has been estimated to 40 and 50 dBm for the soft and the stiff spring actuators, respectively. The fabrication is done by a single-mask silicon-on-insulator RF MEMS process.
Place, publisher, year, edition, pages
2011. 1087-1090 p.
, European Microwave Week 2011: "Wave to the Future", EuMW 2011, Conference Proceedings - 41st European Microwave Conference, EuMC 2011
micromachined transmission lines, RF MEMS, tuneable filters, 3D transmission, A-center, Actuation voltages, Advanced design system, Agilent, Basic concepts, Capacitive loads, Fabricated device, Filter-based, Ground layer, MEMS actuators, Multi-step, Pass bands, Reconfigurable filters, Return loss, RF signal, RF-MEMS, Self actuation, Silicon on insulator, Single-mask, Spring actuators, Spring constants, Transmission line, Tuning mechanism, Tuning ranges, Actuators, Capacitors, Coplanar waveguides, Design, Electric lines, Electrostatic actuators, Metallizing, Three dimensional, Transmission line theory, Tuning, Microwave filters
Other Electrical Engineering, Electronic Engineering, Information Engineering
IdentifiersURN: urn:nbn:se:kth:diva-149928ScopusID: 2-s2.0-84855790490ISBN: 9782874870224OAI: oai:DiVA.org:kth-149928DiVA: diva2:744731
14th European Microwave Week 2011: "Wave to the Future", EuMW 2011 - 41st EuropeanMicrowave Conference, EuMC 2011, 10 October 2011 through 13 October 2011, Manchester
QC 201409082014-09-082014-08-282014-09-08Bibliographically approved