Low-loss lateral micromachined switches for high frequency applications
01 Jan 2005-Journal of Micromechanics and Microengineering (IOP Publishing)-Vol. 15, Iss: 1, pp 157-167
TL;DR: In this article, two novel lateral metal-contact radio-frequency microelectromechanical system (RF MEMS) switches are reported, implemented with quasi-finite ground coplanar waveguide (FGCPW) configuration and actuated by applying electrostatic force on a high-aspect-ratio cantilever beam.
Abstract: Two novel lateral metal-contact radio-frequency microelectromechanical system (RF MEMS) switches are reported. These switches are implemented with quasi-finite ground coplanar waveguide (FGCPW) configuration and actuated by applying electrostatic force on a high-aspect-ratio cantilever beam. It is demonstrated that the insertion loss of the switch is less than 0.2 dB up to 15 GHz and the isolation is higher than 20 dB up to 25 GHz. An RF model of the switches is used to analyse the effects of the switch design parameters and RF performance. The optimization of the switch mechanical design is discussed where the threshold voltage can be lower than 25 V. The lateral switches are fabricated by deep reactive ion etching (DRIE) process on a silicon-on-insulator (SOI) wafer with shadow mask technology.
Citations
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TL;DR: In this article, a waveguide switch based on a reconfigurable surface is proposed, whose working principle is to block the wave propagation by blocking the wave pruning operation on the switch.
Abstract: This paper presents for the first time a novel concept of a microelectromechanical systems (MEMS) waveguide switch based on a reconfigurable surface, whose working principle is to block the wave pr ...
10 citations
05 Jun 2011
TL;DR: In this paper, the authors developed an electrothermally driven RF MEMS capacitive switch, where the HfO 2 film, deposited by atomic layer deposition (ALD) process, was used as insulation dielectric of the capacitor formed by the signal line and switching plate.
Abstract: In this paper, we developed an electrothermally driven RF MEMS capacitive switch, where the HfO 2 film, deposited by atomic layer deposition (ALD) process, was used as insulation dielectric of the capacitor formed by the signal line and switching plate. Thanks high permittivity and excellent electrical and thermal isolation properties of the HfO 2 film, as well as high driving force of the electrothermal actuator, the single side isolation of the proposed switch with HfO 2 film was up to 17dB at 20GHz. The results demonstrate that the HfO 2 film is a good candidate material acting as sidewall dielectric to realize the lateral capacitive switch.
10 citations
Cites methods from "Low-loss lateral micromachined swit..."
...Currently, some laterally-driven MEMS switches have been fabricated and reported, such as the lateral RF MEMS switch based on SOI substrate [4], multi-contact MEMS relays based on laterally actuated comb actuators [5], highly reliable lateral MEMS switch utilizing undoped polysilicon as isolation material [6], and the double stop comb driven RF MEMS switch [7]....
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01 Jan 2012-Microsystem Technologies-micro-and Nanosystems-information Storage and Processing Systems
TL;DR: In this article, a lateral RF MEMS capacitive switch was reported, which employed parylene as the dielectric material, taking advantage of its low temperature deposition and conformal coating.
Abstract: A novel lateral RF MEMS capacitive switch was reported in this paper. This switch employed parylene as the dielectric material, taking advantages of its low temperature deposition and conformal coating. The low resistivity single crystalline silicon served as the material of the mechanical structures. The switch was fabricated by bulk micromachining processes with only two lithographic masks and a shadow mask. The dynamical response, parylene insulation performance, and RF performances of the fabricated switch were characterized, respectively. The switching time from the open state to the close state was 105 μs at a loaded voltage of 78 V, while 15.6 μs from the close state to the open state. The isolation was better than 15 dB from 20 to 40 GHz, and the maximal isolation was 23.5 dB at 25 GHz; while the insertion loss was below 1.4 dB at 25 GHz, when bonding wires connected the ground lines. These results verify that the parylene is a good candidate material to act as sidewall dielectric to realize the lateral capacitive switch.
10 citations
26 Dec 2007
TL;DR: In this article, an electrostatically actuated MEMS switch mechanism for a mechanically tri-stable single-pole-double-throw (SPDT) metal-contact switch is presented.
Abstract: This paper presents an electrostatically actuated MEMS switch mechanism for a mechanically tri-stable single- pole-double-throw (SPDT) metal-contact switch, which is fully embedded in the signal line of a low-loss 3D-micromachined coplanar-waveguide T-junction. The switch features mechanical tri-stability, i.e. all three stable states of the switch are maintained by an interlocking mechanism without applying external actuation energy. The actuation voltage is only necessary for triggering the transition between the three stable states. In contrast to conventional MEMS switch designs where the switch actuator is built around the transmission line and thus creates a discontinuity in the waveguide, the switch mechanism of the presented design is completely embedded in the signal line of the coplanar waveguide. This, together with a 3D micromachined transmission line design confining the major part of the field lines in the air and not in the substrate, results in very low insertion loss and low reflections. Furthermore, the switches feature active opening which results in very reliable operation of the switches. Single-pole-double-throw metal-contact switches have been fabricated in a very simple, single photolithography mask process, and successfully evaluated from DC to 15 GHz.
9 citations
Cites background from "Low-loss lateral micromachined swit..."
...Laterally moving electrostatically actuated MEMS switches are very uncomplicated to fabricate and very robust to operate [6], [7], [8]....
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04 Dec 2005
TL;DR: In this article, a single-pole-double-throw (SPDT) switch circuit using high-aspect-ratio lateral RF microelectromechanics system (MEMS) switches has been designed to operate from DC to 20 GHz by using lateral switches and coplanar waveguide configuration.
Abstract: A new single-pole-double-throw (SPDT) switch circuit using high-aspect-ratio lateral RF microelectromechanics system (MEMS) switches has been designed to operate from DC to 20 GHz By using lateral switches and coplanar waveguide configuration, compactness and low-loss can be obtained The circuit provides greater than 22 dB isolation and less than 09 dB insertion losses up to 20 GHz A low-cost high-yield silicon-on-glass (SOG) fabrication process has been developed to fabricate this SPDT switch circuit The size of the whole circuit is only 164 mm /spl times/ 13 mm in area
9 citations
Cites background from "Low-loss lateral micromachined swit..."
...Recently lateral switches fabricated by bulk micromachining process have been studied, which have the benefit of co-fabrication and flexibility of inplane actuator design [5, 6]....
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References
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TL;DR: In this paper, the construction and performance of metal membrane radio frequency MEMS switches at microwave and millimeter-wave frequencies was described. But the authors focused on the performance of the switches in terms of on-off capacitance ratio.
Abstract: 'This letter details the construction and performance of metal membrane radio frequency MEMS switches at microwave and millimeter-wave frequencies. These shunt switches possess a movable metal membrane which pulls down onto a metal/dielectric sandwich to form a capacitive switch. These switches exhibit low loss (<0.25 dB at 35 GHz) with good isolation (35 dB at 35 GHz). These devices possess on-off capacitance ratios in the range of 80-110 with a cutoff frequency (figure of merit) in excess of 9000 GHz, significantly better than that achievable with electronic switching devices.
474 citations
"Low-loss lateral micromachined swit..." refers background in this paper
...Most of the reported MEMS switches are vertical motion switches, including the fixed–fixed beam switch [1], cantilever beam switch [2], toggle switch [3] and push–pull switch [4]....
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TL;DR: In this paper, the authors evaluate the potential of using high-resistivity silicon as a low-cost low-loss microwave substrate through an experimental comparative study and demonstrate that the losses of a coplanar transmission line (CPW) realized on high resistivity (3 k to 7 k /spl Omega/-cm) silicon substrates are comparable to the losses realized on a GaAs substrate covered with insulators.
Abstract: Silicon has many advantages as a microwave substrate material including low cost and a mature technology. The aim of this paper is to evaluate the potential of using high-resistivity silicon as a low-cost low-loss microwave substrate through an experimental comparative study. Coplanar waveguides fabricated on Si, GaAs, and quartz substrates are tested and their characteristics are compared. Microwave spiral inductors and meander lines are also fabricated on various substrates, and their performance is also analyzed. The results demonstrate that the losses of a coplanar transmission line (CPW) realized on high-resistivity (3 k to 7 k /spl Omega/-cm) silicon substrates are comparable to the losses of a CPW realized on a GaAs substrate covered with insulators. Furthermore, measured unloaded Q's of microwave inductive structures on high-resistivity silicon substrates are comparable to the measured unloaded Q's of the same structures on GaAs and on quartz. This paper demonstrates that high-resistivity Si can be used as a microwave substrate. >
171 citations
"Low-loss lateral micromachined swit..." refers background in this paper
...High resistivity (HR) silicon (Si) has been studied as a substrate material for communication system applications at microwave and millimetre wave frequencies for its mature fabrication process, low cost and acceptable RF performance [13]....
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11 Jun 2000
TL;DR: In this article, a push-pull type microwave switch is proposed, which utilizes torsion springs and leverage for lowvoltage operation, and the actuation voltage is /spl sim/5 V.
Abstract: In this paper, a push-pull type microwave switch is proposed, which utilizes torsion springs and leverage for low-voltage operation. The switching operation up to 4 GHz is demonstrated. The actuation voltage is /spl sim/5 V. The insertion loss of /spl sim/1 dB and the isolation as high as /spl sim/40 dB at 1 GHz are achieved by the push-pull operation.
138 citations