Comparative Study of Cantilever RF MEMS Switch (original) (raw)
Related papers
In a MEMS based RF switch Cantilever beam is an element that is fixed at one end and free from another side. The electrostatic actuation process occurs on the beam and it will deflect from an original position. As the Electrostatic force increases, the z-component displacement produced in the beam is also increases. The beam is placed at the 2µm height from the ground substrate. The cantilever works as a switch which operates as ON or OFF. When the switch is ON its capacitance increases and when it is OFF its capacitance decreases. When applied actuation voltage reaches to Pull-in-voltage the cantilever connects with the ground electrode. This paper explores the concept of increase in flexibility, switching speed, low power consumption, low actuation voltage and reduction in squeeze film damping. The various types of cantilever switch provide discrete displacement corresponding to actuation voltage. In this paper we simulated the cantilever switch with various shapes. The simulation is done using COMSOL MULTIPHYSICS software.
A Novel Design of Cantilever RF MEMS Series Switch
This paper presents novel design of various configurations of cantilever type Radio Frequency Micro Electro Mechanical Systems (RF MEMS) Series Switch. The paper emphasizes on study of Actuation Voltage of RF MEMS switches. Actuation voltages of uniform cantilever switches has been compared with cantilever switches supported on three bars (non-uniform switch) for various geometric configuration and material properties. It is observed from the simulation results that reduction in actuation voltage as high as 5V can be achieved by reducing the anchorage width. Also, use of mica with higher dielectric constant over silicon nitride as dielectric layer yields considerable reduction in actuation voltage.
Design of low actuation voltage RF MEMS cantilever switch
2008 International Conference on Recent Advances in Microwave Theory and Applications, 2008
This paper presents novel design of various configurations of cantilever type Radio Frequency Micro Electro Mechanical Systems (RF MEMS) Series Switch. The paper emphasizes on study of Actuation Voltage of RF MEMS switches. Actuation voltages of uniform cantilever switches has been compared with cantilever switches supported on three bars (non-uniform switch) for various geometric configuration and material properties. It is observed from the simulation results that reduction in actuation voltage as high as 5V can be achieved by reducing the anchorage width. Also, use of mica with higher dielectric constant over silicon nitride as dielectric layer yields considerable reduction in actuation voltage.
DESIGN OF STICTIONFREE LOWER PULL IN VOLTAGE RF MEMS SWITCH USING FISHBONE CANTILEVER BEAM 1
2018
A new fishbone structure cantilever beam type RF MEMS switch has been proposed. The main advantage of this switch is that it is inherently stiction free and therefore enhances design flexibility. An analytical model developed using unit load approach for the spring constant of the proposed switch has been presented and it has been shown that the spring constant and therefore the pull in voltage (Vpi) can be considerably reduced with the proposed switch. Simulation studies conducted on two groups of devices clearly demonstrate that the pull in voltage can be reduced by 65% with ten sections. Comparision of the pull in voltage obtained in the simulation studies for devices with the theoretically estimated Vpi shows that the spring constant model presented in this paper accurately estimates the spring constant. The results of analytical studies also demonstrate that the new proposed cantilever beam can considerably reduce the pull in voltage.
A Review Paper on MEMS Cantilever Radio Frequency Switch
Shweta M. Shingare & Syed A. Naveed, 2013
This paper deals with the MEMS (Micro-Electro-Mechanical-System) Cantilever RF (Radio Frequency) switch. These switches exhibit low insertion loss and better isolation at sufficiently high frequencies. The dominance of Cantilever RF-Switch also explains the spring constant for cantilever, pull-in voltage, hold-down voltage, resonant frequency for cantilever to be used as resonators or any high frequency applications. The dominance of RF- Switch also explains with the size, power, isolation, insertion loss. This paper explains graphically how Pull-in voltage affects on the tip deflection of the switch and switching time.
Development of a low stress RF MEMS double-cantilever shunt capacitive switch
Microsystem Technologies, 2020
In this paper, a novel RF MEMS shunt capacitive switch with application in the Ka frequency band is proposed. The spring design and the step structure added to the beam succeeded in improving the performance of the switch and reducing the stress which results in extended lifetime of the switch. Also, by optimally reducing the gap between the dielectric and the beam (without problems such as self-actuation), the actuation voltage of the switch is significantly reduced. Electromechanical and scattering parameters analysis have been done by using COMSOL Multiphysics and HFSS software, respectively. The actuation voltage of the proposed device is 9.2 V. Since the aluminum has a lower mass compared to gold, an aluminum beam has been used in the switch. Desirable scattering parameters at the resonance frequency of 33.5 GHz have been obtained which include insertion loss of-0.3 dB and return loss of-18 dB. The high isolation of-57 dB verifies the improved performance of the switch. Finally, as another innovation in this paper, the effect of inductor and capacitor presence in the input of transmission line is investigated. This analysis has been done by using ADS. Results of the circuit analysis presented in this paper, help the MEMS switch designers to understand the realistic switch behavior before fabrication which considerably saves cost and time.
Mechanical Design of RF MEMS Capacitive Switches
2000
This paper analyses the mechanical behaviour of various suspensions of electrostatically actuated RF MEMS switches. A family of capacitive switches is described, with suspensions varying step by step from cantilevers to meander shaped double clamped beams. The result is a capacitive shunt switch with a designed actuation voltage of 4.5 V, and 20dB isolation and 0.04 dB insertion loss at a frequency of 2 GHz. At the time of writing, the proposed devices are being processed.
Contact physics modeling and optimization design of RF-MEMS cantilever switches
2005
RF MEMS direct-contact switches exhibit many advantages over the conventional semiconductor switches; however, existing drawbacks such as low power handling, high pull-in voltage and long switch opening time are most critical. This paper presents an optimization design for an RF-MEMS cantilever direct-contact switch to achieve maximum power handling capability, minimum pull-in voltage and switch opening time simultaneously. A 2-step optimization technique is proposed to achieve the optimal design to allow for a power handling capability of 130 mW, a pull-in voltage of 52 V, and a switch opening time 4.4 μs presented. The optimization results show that substantial room exists for improving the current designs of RF MEMS direct-contact switches.
2018
This paper presents a novel cantilever based RF MEMS series switch. The cantilever is of a dielectric material to prevent crosstalk and for isolation between the RF and DC signal. This switch has low actuation voltage and good RF performance in the frequency range from 2 to 12 GHz. Low actuation voltages are achieved by varying the spring constant of the beam. The spring constant of the beam can be varied by varying the geometry of the beam. We have introduced geometrical variations in the beam design that have led to low actuation voltage and good RF performance. A meander shaped beam is proposed which gives the least actuation voltage. The meanders in the beam reduce the spring constant without affecting the RF performance of the switch. The proposed design has a very low Pull in voltage of 6.64V. The RF performance of the switch shows that the Return loss is-25.65dB at 9.8GHz.The isolation is about-64.02dB and the insertion loss is about -0.2065dB at 9.7GHz
Robust Design of RF-MEMS Cantilever Switches Using Contact Physics Modeling
IEEE Transactions on Industrial Electronics, 2009
This paper presents the robust design optimization of an RF-MEMS direct contact cantilever switch for minimum actuation voltage and opening time, and maximum power handling capability. The design variables are the length and thickness of the entire cantilever, the widths of the sections of the cantilever, and the dimple size. The actuation voltage is obtained using a 3-D structural-electrostatic finite-element method (FEM) model, and the opening time is obtained using the same FEM model and the experimental model of adhesion at the contact surfaces developed in our previous work. The model accounts for an unpredictable variance in the contact resistance resulting from the micromachining process for the estimation of the power handling. This is achieved by taking the ratio of the root mean square power of the RF current ("signal") passing through the switch to the contact temperature ("noise") resulting from the possible range of the contact resistance. The resulting robust optimization problem is solved using a Strength Pareto Evolutionary Algorithm, to obtain design alternatives exhibiting different tradeoffs among the three objectives. The results show that there exists substantial room for improved designs of RF-MEMS direct-contact switches. It also provides a better understanding of the key factors contributing to the performances of RF-MEMS switches. Most importantly, it provides guidance for further improvements of RF-MEMS switches that exploit complex multiphysics phenomena.