Design Of MEMS Switch Research Articles

Design of a graphene RF MEMS switch for X–V band

In this paper, we propose a graphene RF MEMS switch design for the X–V band. The structural parameters of graphene, such as the number of layers, the thickness of the medium and the material of the upper electrode, were analyzed by HFSS simulation software. The drive voltage of the switch was found to be as low as 3 V. The switching time is 320 ns. The highest isolation is −47.46 dB@8 GHz; In the 2–56 GHz band, the isolation is better than −20dB. Moreover, we carry out the process design of the switch, including key techniques such as graphene beam fabrication and graphene transfer, it shows that the switch has a great application prospect in the future.

Design and fabrication of a series contact RF MEMS switch with a novel top electrode

Radio-frequency (RF) micro-electro-mechanical-system (MEMS) switches are widely used in communication devices and test instruments. In this paper, we demonstrate the structural design and optimization of a novel RF MEMS switch with a straight top electrode. The insertion loss, isolation, actuator voltage, and stress distribution of the switch are optimized and explored simultaneously by HFSS and COMSOL software, taking into account both its RF and mechanical properties. Based on the optimized results, a switch was fabricated by a micromachining process compatible with conventional IC processes. The RF performance in the DC to 18 GHz range was measured with a vector network analyzer, showing isolation of more than 21.28 dB over the entire operating frequency range. Moreover, the required actuation voltage was about 9.9 V, and the switching time was approximately 33 μs. A maximum lifetime of 109 switching cycles was obtained. Additionally, the dimension of the sample is 1.8 mm × 1.8 mm × 0.3 mm, which might find application in the current stage.

Performance Exploration of Uncertain RF MEMS Switch Design with Uniform Meanders

The design of RF-MEMS Switch is useful for future artificial intelligence applications. Radio detection and range estimation has been employed with RF MEMS technology. Attenuators, limiters, phase shifters, T/R switches, and adjustable matching networks are components of RF MEMS. The proposed RF MEMS technology has been introduced in T/R modules, lenses, reflect arrays, sub arrays and switching beam formers. The uncertain RF MEMS switches have been faced many issues like switching and voltage alterations. This study aims in the direction of design, simulation, model along with RF MEMS switching analysis including consistent curving or meandering. The proposed RF MEMS Switch is a flexure form of the Meanders that attain minimal power in nominal voltage. Moreover, this research work highlights the materials assortment in case of beam along with signal-based dielectric. The performance analysis is demonstrated for various materials that have been utilized in the design purpose. Further, better isolation is accomplished at the range of -31dB necessary regarding 8.06V pull-in voltage through a spring constant valued at 3.588N/m, switching capacitance analysis has been found to be 103 fF at ON state and 7.03pF at OFF state and the proposed switch is optimized to work at 38GHz. The designed RF MEMS switch is giving 30% voltage improvement; switching frequency is improved by 21.32% had been attained, which are outperformance the methodology and compete with present technology.

THz MEMS Switch Design

In this work, an mm-wave/THz MEMS switch design process is presented. The challenges and solutions associated with the switch electrical design, modeling, fabrication, and test are explored and discussed. To investigate the feasibility of this design process, the switches are designed on both silicon and fused quartz substrate and then tested in the 140–750 GHz frequency range. The measurement fits design expectations and simulation well. At 750 GHz the measurement results from switches on both substrates have an ON state insertion loss of less than 3 dB and an OFF state isolation larger than 12 dB.

Design, Simulation and Analysis of Perforated RF MEMS Capacitive Shunt Switch

Objective: This paper presents the design and simulation of double bridge-type capacitive RF MEMS switch by using FEM Tool. Methods: It is mainly concentrated on a low pull-in voltage, capacitance, and RF analysis. The beam is considered as a gold metal having the length of 595 μm along with the 1μm thickness and the dielectric is taken as Silicon nitride (Si3N4) by using Ashby’s method. The non-uniform meandering technique and perforations are used to reduce the pull-in voltage, by changing different beam thickness, air gap and materials. Results: The pull-in voltage of the proposed RF MEMS switch is 1.2 V. The scattering parameters are simulated by using Ansoft HFSS software. The simulation results of S-parameters such as return loss, insertion losses are, -19.27 dB and -0.20dB. The switch having good isolation is -63.94 dB at 8 GHz. Conclusion: The overall switch is designed with different beam thickness, various gap, and different materials to identify the best performance of the switch for low-frequency applications i.e X-bands.

Analytical modelling, design optimisation and numerical simulation of a variable width cantilever beam MEMS switch

ABSTRACT Pull-in potential of electrostatic actuation ohmic cantilever beam type RF MEMS switch is lowered by reducing stiffness constant of its cantilever beam. However, this design objective is highly interlinked to major criteria like its mechanical, RF performance parameters, materials used and fabrication constraints. The purpose of this study is to address the design methodology of such interdisciplinary complex phenomenon to obtain global optimum solution. A variable width cantilever beam design is proposed to lower its pull-in potential. The design optimisation methodology adopted in this study uses analytical model of stiffness constant, major interlinked criteria based on cantilever beam profile and geometric dimensions of the switch. This methodology is further identified as a multivariable constraint optimisation problem to be solved using evolutionary optimisation algorithm for various geometric dimensions of the switch. 3-D modelling, simulation of the optimised device for pull-in potential, mechanical and RF performance parameters is carried out using CAD tools. The results obtained from simulation and analytical models are in agreement. The proposed optimised design opens a new avenue in RF MEMS switch design as it satisfies additional essential performance parameters compared to the results of previous published designs concluding significance of design optimisation methodology adopted in this work.

WITHDRAWN: Design and performance analysis of novel bridge type RF MEMS switch for X-band

Abstract This is a unique design and performance review of bridge model Radio Frequency (RF) MEMS switch accompanied by perforations and uniform meanders are presented. This paper is mainly focused on reducing the pull-in (Vp) voltage and increasing the isolation of RF shunt switch. Electromechanical and Electromagnetic analysis is done by utilizing FEM and HFSS tools. With changing the different beam materials, thickness and gap from the beam to dielectric signal and to compute the spring constant (K) and pull-in (Vp) voltage. The perforations and meanders are used for reduction in pull-in (Vp) voltage, and it is obtained as 18.5 V, the up state and downstate switching capacitance is reported as 5.12Ff and 3.27 pF. The switch exhibits good switching time is 2.5 µs. The RF-analysis is getting tremendous results like return los at −38.60 dB, insertion loss of the suggested type switch is at −0.1177 Decibels, and the isolation has been maintained as −37.20 dB at 8 GHz frequency. The performance of bridge type switch is shown at 8 to 12 GHz (X-band) frequency. So, the bridge type switch is pertinent for low frequencies like satellite and military needs.

Design and Simulation of Capacitive MEMS Switch for Ka Band Application

In this paper, RF MEMS switch with capacitive contact is designed and analyzed for Ka band application. A fixed‐fixed beam/meander configuration has been used to design the switch for frequency band 10 GHz to 40 GHz. Electromagnetic and electromechanical analysis of three‐dimensional (3D) structure/design has been analyzed in multiple finite element method (FEM) based full‐wave simulator (Coventorware and high‐frequency structure simulator). A comparative study has also been carried out in this work. The high resistivity silicon substrate (tanδ = 0.010, ρ > 8 kΩ − cm, εr = 11.8) with a thickness of 675 ± 25 μm has been taken for switch realization. The designed structure shows an actuation voltage of around 9.2 V. Impedance matching for the switch structure is well below 20 dB, loss in upstate, i.e., insertion loss >0.5 dB, and isolation of >25 dB throughout the frequency band is observed for the aforesaid structure. Furthermore, to increase the RF parameters, AIN dielectric material has been used instead of SiO2 resulting in capacitance in downstate that increases hence improved the isolation. The proposed switch can be utilized in various potential applications such as any switching/tunable networks phased‐array radar, reconfigurable antenna, RF phase shifter, mixer, biomedical, filter, and any transmitter/receiver (T/R) modules.

Design and Fabrication of Reliable Power Efficient Bistable MEMS Switch Using Single Mask Process

A bistable DC switch based on buckled beams and thermal actuation has been designed, fabricated and characterised. The buckled beams, which require very low actuation force and provide a sufficiently large contact force, are designed based on a parametric study. U-shaped thermal actuators are designed to provide the actuation force with minimum electrical power. The compact switch is fabricated using a simple single mask process on a SOI wafer. The average switching power is measured to be 60 $mW$ , while the average switching delay is 350 ${\mu }s$ . The power-delay product of about $20~{\mu }J$ is the lowest reported so far for bistable MEMS switches based on thermal actuation. The switch retains functionality even after 5 million switching cycles. [2020-0026]

Metal contact RF MEMS switch design for high performance in Ka band

RF/microwave systems require switches to achieve tunability and reconfigurability. MEMS switches have always been a priority due to excellent RF performance (low insertion loss and high isolation). In this work, we present an RF Micro-Electro-Mechanical-System (RF MEMS) series switch that provides insertion loss less than 0.6 dB (on switch) and isolation better than 15 dB (off switch) at 40GHz. The designed switch consists of serpentine arms on the fixed end and two free-moving arms on another end. These free arms have individual contact points to overcome asperity problem during on state. To avoid self-actuation, bumps (0.6um) are used at the bottom side. This electrostatically actuated switch requires a pull-in voltage of 3.1V for 2.4 μm displacement in 67.14 μs time. The proposed switch is analysed in COMSOL software, and its RF characteristics are simulated in HFSS.

Design and simulation of capacitive SPDT RF MEMS switch to improve its isolation

This paper presents the simulation and analysis of capacitive shunt SPDT RF MEMS switch for high radio frequency applications. The design is based on the shunt configuration consisting of 2 capacitive type switches. To reduce pull in voltage, the high-frequency capacitive SPDT switch is proposed. The beam is designed with non-uniform meanders with perforations. By using the COMSOL Multiphysics tool, we found the pull-in voltage as 1.5 V at a beam thickness of 0.5 μm. The corresponding capacitance ratio is 44 for the dielectric of Silicon Nitrate. The up sate and downstate capacitance of the switch is calculated and simulated. The performance analysis is done by using HFSS tool and is found to RF-perform excellently at 28 GHz with isolation of − 68 dB, the return and insertion losses are − 61 dB and − 0.1 dB respectively.

Design and Analysis of Series Configuration-Based Mems Switch

This paper reports the design and analysis of series type MEMS switch. This switch can be used for tunable filter applications from DC-10GHz frequency range. The study briefly explains the design of switch and analysis of various switching parameters. Through electrostatic actuation mechanism the switch is optimized in terms of various parameters like beam thickness, beam width, airgap, conductor and dielectric materials. Study of proposed design with COMSOL for electromechanical analysis and HFSS for electromagnetic analysis. The switch has theoretical and simulated actuation voltages of 22.81V and 38V respectively. It has the switching time of 33.36μs. The upstate and down state capacitances of 0.286pF, 3.93fF respectively. When the switch is in ON state an insertion loss of less than -0.1dB and return loss of -15dB is achieved. When the switch is in OFF state an isolation loss of -0.1dB and return loss of -21dB is achieved at 3GHz.

Design and Analysis of Shunt Configuration-Based RF MEMS Switch

In this paper a shunt type RF MEMS switch design and analysis for tunable applications is presented. Switch works based on the electrostatic actuation principle. Theoretical calculated Switch parameters are compared with the electromechanical and electromagnetic simulation results. The effect of various materials like conductor and dielectrics & parameters like airgap, beam width on the electromechanical parameters of the switch is analyzed to get low pull-in voltage, high switching speed, better capacitance ratio, return loss, insertion loss, and isolation loss. The switch up and down state capacitance are 40.9fF and 4.45pF respectively. Down to up state capacitance ratio of this switch is 108.69. The designed switch has an actuation voltage of 32V. RF performance is simulated from 1-10GHz. In ON state switch has return loss of -35dB, insertion loss of -0.1dB. In the OFF-state switch has return loss of -1dB and an isolation loss of -11dB.

Design and Performance of a J Band MEMS Switch.

This paper presents a novel J band (220–325 GHz) MEMS switch design. The equivalent circuits, the major parameters, capacitance, inductance and resistance in the circuit were extracted and calculated quantitatively to carry out the radio frequency analysis. In addition, the mechanical property of the switch structure is analyzed, and the switching voltage is obtained. With the designed parameters, the MEMS switch is fabricated. The measurement results are in good agreement with simulation results, and the switch is actuated under a voltage of ~30 V. More importantly, the switch has achieved a low insertion loss of ~1.2 dB at 220 GHz and <~4 dB from 220 GHz to 270 GHz in the “UP” state, and isolation of ~16 dB from 220 GHz to 320 GHz in the “DOWN” state. Such switch shows great potential in the integration for terahertz components.

On characterization of symmetric type capacitive RF MEMS switches

This paper presents the design, fabrication and characterization of capacitive type MEMS switch for space and terrestrial communication applications. The deviation in measured actuation voltage and RF response of the switches are discussed in terms of the process variation which occurred unintentionally during the fabrication of devices. For example the measured actuation voltage is 15 V, about 20% higher than the designed voltage of 12.25 V. The deviation corresponds to the increase in thickness of the membrane while electroplating. The impact of process parameters on mechanical resonance frequency of the switches, and on/off time is also discussed. Measured S-parameters shows isolation of > − 20 dB for 7–16 GHz and an insertion loss better than − 0.6 dB up to 20 GHz. The capacitance ratio of the fabricated switch is 77, which is 15% lower than the designed capacitance ratio. The switch has been tested for 1 million 65 thousand cycles without switching failure. The deviation of simulated and measured results is discussed in the following sections.

Design and Optimization of AlN based RF MEMS Switches

Radio frequency microelectromechanical system (RF MEMS) switch technology might have potential to replace the semiconductor technology in future communication systems as well as communication satellites, wireless and mobile phones. This study is to explore the possibilities of RF MEMS switch design and optimization with aluminium nitride (AlN) thin film as the piezoelectric actuation material. Achieving low actuation voltage and high contact force with optimal geometry using the principle of piezoelectric effect is the main motivation for this research. Analytical and numerical modelling of single beam type RF MEMS switch used to analyse the design parameters and optimize them for the minimum actuation voltage and high contact force. An analytical model using isotropic AlN material properties used to obtain the optimal parameters. The optimized geometry of the device length, width and thickness are 2000 µm, 500 µm and 0.6 µm respectively obtained for the single beam RF MEMS switch. Low actuation voltage and high contact force with optimal geometry are less than 2 Vand 100 µN obtained by analytical analysis. Additionally, the single beam RF MEMS switch are optimized and validated by comparing the analytical and finite element modelling (FEM) analysis.

Novel analytical model for optimizing the pull-in voltage in a flexured MEMS switch incorporating beam perforation effect

This paper presents a new method for the design, modelling and optimization of a uniform serpentine meander based MEMS shunt capacitive switch with perforation on upper beam. The new approach is proposed to improve the Pull-in Voltage performance in a MEMS switch. First a new analytical model of the Pull-in Voltage is proposed using the modified Mejis-Fokkema capacitance model taking care of the nonlinear electrostatic force, the fringing field effect due to beam thickness and etched holes on the beam simultaneously followed by the validation of same with the simulated results of benchmark full 3D FEM solver CoventorWare in a wide range of structural parameter variations. It shows a good agreement with the simulated results. Secondly, an optimization method is presented to determine the optimum configuration of switch for achieving minimum Pull-in voltage considering the proposed analytical mode as objective function. Some high performance Evolutionary Optimization Algorithms have been utilized to obtain the optimum dimensions with less computational cost and complexity. Upon comparing the applied algorithms between each other, the Dragonfly Algorithm is found to be most suitable in terms of minimum Pull-in voltage and higher convergence speed. Optimized values are validated against the simulated results of CoventorWare which shows a very satisfactory results with a small deviation of 0.223V. In addition to these, the paper proposes, for the first time, a novel algorithmic approach for uniform arrangement of square holes in a given beam area of RF MEMS switch for perforation. The algorithm dynamically accommodates all the square holes within a given beam area such that the maximum space is utilized. This automated arrangement of perforation holes will further improve the computational complexity and design accuracy of the complex design of perforated MEMS switch.

A small size Ka band six-bit DMTL phase shifter using new design of MEMS switch

This paper presents a new design of MEMS switch to achieve a six-bit small size and low loss DMTL phase shifter. In the proposed structure two electrodes are added to the universal MEMS capacitive switch. These additional electrodes are placed near the center line under the bridge. By using these electrodes it is possible to create two phase states in a unit cell. The structure is calculated and simulated at 30 GHz using MATLAB and HFSS softwares, respectively. According to calculation and simulation results for all phase states the return loss is better than ź10 dB. Using this design the number of cells is decreased considerably. As a result the size and loss are decreased. The design can be easily scaled to other frequencies with more bits.

Robust Design of RF MEMS Switch Design with Reduced Buckeling Effect

RF MEMS switches are used in many applications and also can be used to achieve reconfigurability of various RF systems and in particular, that of minute sized antenna structures and systems. In the case of micro machined antennas, which usually have low voltage signals, RF MEMS switches with low actuation voltage are highly required for achieving reconfigurability. The capacitive shunt switch derives its switching property from the significant difference of its capacitance in the up-state and down-state. We have presented a highly reliable RF MEMS switch. We have used various small beams to achieve reliably. Basically the stiction and buckling effect can be reduced by using such a structure. The actuation voltage of RF MEMS switches mainly depends on the spring constant of the switch membrane. A low actuation voltage capacitive shunt switch, is presented. A process flow for the fabrication is designed and simulated using HFSS. The EM analysis results are presented and compared with that of a fixedfixed flexure based switch membrane to establish the low actuation voltage. Reliable can be seen from the vertical structure [22-26].

CANTILEVER TYPE SWITCH DESIGN

This paper deals with the RF (Radio Frequency)-MEMS (Micro-Electro-Mechanical-System) switch design using the coventorware software and its superiority over the existing technologies like PIN Diodes and Field-Effect-Transistors regarding size, power, Isolation and Insertion loss, and graphically how Pull-in voltage affects on the deflection of the switch. Also this paper deals with the fabrication process of the cantilever switch.