Basic concepts and applications with matlab, maple, and comsol, 3 rd edition darrell w. A dc voltage greater than the pullin voltage is applied across the switch, causing the bridge to collapse onto the dielectric layer with a resulting increase in the capacitance of the device. Design and simulation of rf mems shunt capacitive switch. Here it is again, serving as a quick intro to modeling rf and microwave heating. How to model electromechanics in comsol multiphysics.
Three primary performance indices, pullin voltage, rf loss, and thermal residual stress, are used to obtain. Mechanical systems are switches and variable capacitors, which are used in the front. The switch is a capacitive type, which is actuated by an electrostatic force. Typical examples coaxial cable optical fibers and waveguides waveguides and transmission lines z. Tutorial on comsol multiphysics platform comsol is a multiphysics platform, which will be used to do all your simulations.
The simulation results show that return loss can reach21. This stepbystep instructional video shows you how the electromechanics interface in comsol multiphysics couples and solves mechanical and electrical problems. It provides an overview of the comsol environment with examples that show you how to use the comsol desktop user interface and the model builder. In the comsol multiphysics software any number of physics can be combined in one and the same simulation. The structure of the switch consists of a cpw coplanar waveguides transmission lines and a suspended membrane. Piezoelectric pressure sensor is also designed with circular radius of 180. Contact studies for reliable ohmic switch as discussed in introduction of rf mems ohmic switches, the major problem in ohmic switches is the contact degradation.
Modeling method of finite element modeler and electromagnetic. May 20, 2014 we like to feature a certain waveguide model in our rf and microwave heating webinars because it illustrates the concept in a way that is easy to understand. Despite its simplicity, and the fact that very few engineers would run a structural analysis before trying to turn. Design and of analysis of spdt ohmic rf mems switch. It also provides a quick introduction to creating applications using the application builder. The proposed design consist of mechanical structure with microcantilever beam and capacitive contact type.
Fabrication and modeling of piezoelectric rf mems resonators. Besides rf mems technology, iiiv compound semiconductor gaas, gan, inp, insb, ferrite, ferroelectric. The user can simulate a design, test for the capacitance and observe the effects on capacitance by changing parameters such as dielectric permittivity of materials. The application gallery features comsol multiphysics. I tried few examples to calculate rf mems pullin voltage, but many a times. Rf mems switch saw filter baw filter tunable cavity filter linear and rotary motors position controller accelerometer gyroscope load cell pressure sensor energy harvester actuators and sensors rf mems flow control acoustic devices. The electromechanical and electromagnetic analysis of the switch has been done using comsol fem and hfss tools. Multiphysics design optimization of rfmems switch using. Multiphysics modeling of mems devices november 20 executive summary power is increased with dedicated tools. However, photoresistive polymers, typically used for such patterning, are susceptible to the chlorinebased etchants used to pattern aln. Use of comsol multiphysics for automated electrostatic mems. How to calculate the pullin voltage of rf mems switch in comsol.
Chapter 6 contact studies for reliable ohmic switch. A radially polarized piezoelectric tube is simulated, with two sets of boundary conditions. Quick intro to modeling rf and microwave heating comsol blog. This model analyzes an rf mems switch consisting of a thin micromechanical bridge suspended over a dielectric layer. Mar 30, 2016 this paper presents a new rf mems capacitive shunt switch with low voltage, low loss and high isolation for kband applications. Finite element method fem tools are very helpful to design and simulate the rf mems switch.
Modeling mems and piezoelectric devices comsol multiphysics. An explanation on how to model with a programming language is available in yet another book, the comsol multiphysics scripting guide. Rf functionality can be implemented using a variety of rf technologies. Design of low actuation voltage rf mems switch sergio p. These switches are the unambiguous micro mechanical switches that are intended to operate at rf to mm wave frequencies, which mean 0. Different beam materials such as gold, aluminum, and platinum are used to. A novel design of cantilever rf mems series switch iosr journal. Understanding switch behavior and characteristics is important for designers. This archived webinar shows you that by designing mems devices with numerical simulation, you can achieve the highest possible performance. In this design, we have proposed the step structure to reduce the air gap between the bridge and the signal line, thus the actuation voltage is reduced to 2. The simulation is done using comsol multiphysics software. Radiofrequency microelectromechanical system wikipedia.
I sheared for you a model of rf mems switch in comsol via pdf. As i am very new to comsol multiphysics, its very difficult for me to find the procedure for it. This application note serves as a tutorial for mems microphones, providing general characteristics of these devices, both acoustic and mechanical, as well as summarizing the portfolio available from st. This tutorial shows how to couple three physics interfaces to model evaporative cooling. Review all of the rf module updates in further detail below. Two mems chips that have a spst single pole single throw contact configuration are installed on the ceramic package using the flip chip bonding method as shown fig. How to calculate the pullin voltage of rf mems switch in. However, i keep getting errors indication lack of convergence and.
The first case illustrates the inverse piezoelectric effect, and the second case shows the direct piezoelectric effect. I need some tutorials on mems switch simulation in microwave office. The result of rf performance reduces the bucking effect and eliminates the problem of stiction. Bill laumeister, strategic applications engineer oct 04, 2012 abstract.
We first start with an example on a very simple electrostatic actuated rf mems switch. These interactions may be time invariant, time harmonic, or time varying. Comsol, comsol desktop, comsol multiphysics, and livelink are registered trademarks or trade. They require only a lowvoltage, lowcurrent power supply and have a fully independent parallel logic control interface. Geometry of the rf mems switch as modeled in comsol multiphysics together with the mems module. Transient simulation of the closing of a mems switch with. Electrostatically actuated cantilever on comsol youtube. Electromagnetics modeling in comsol multiphysics the acdc and rf modules. When electrostatic force is applied on the fixedfixed beam, beam shifts to downward direction corresponding to zaxis and various displacements at various voltages is obtained. The number of uses for microelectromechanical systems mems is growingthey allow us to. Comsol can compute the radiated energy, far field patterns, losses, gain, directivity, impedance and sparameters by solving the linear problem for the efield typical examples microstrip patch antenna vivaldi antenna.
Electromechanical modeling and simulation of rf mems switches. Capacitive sensor design using comsol provides the user with a wide variety of tools. Since the switch is symmetrical, its only necessary to model one quadrant of the geometry. In a switch like this, the bridge responds to an applied electric potential and voltage by pulling down on the film. Furthermore, this example may also be defined and modeled using components from the following product combinations. I have been trying to find out the pull in voltage of a very basic cantilever based mems switch. Design, simulation and a comparative study of square, rectangular. The analysis is exemplified on a combination wrench during the application of torque on a bolt. The applications of such rf mems switches in reconfigurable antennas were. In a mems based rf switch cantilever beam is an element that is fixed at one end and free.
Mems switches offer the high rf performance and low dc power consumption of electromechanical parts, and the small size, weight, and lowcost features of semiconductor parts. As there are variety of materials available to design engineer, a proper technique to select the best possible material is needed. In this model i make an accurate modeling for electrostatically actuated cantilever on comsol to study its. Rf mems for wireless communications imems01 short course so many passive components. By creating an accurate model in comsol multiphysics, you will see how the electrical, thermal, structural, and fluid components interact with each other. This paper mainly engrossed on improving performance and reliability of rf mems switch.
This paper presents a novel design of a rf mems switch. This paper presents, the design and simulation of rf mems shunt capacitive switch. Electromagnetics modeling in comsol rf module highfrequency modeling. Modelling of different mems pressure sensors using comsol. This work is inspired by the superior performance of electrostatic rf mems switches over the conventional stateoftheart solidstate devices and the potential applications in communication field.
A highpower differential rf mems spst switch a highpower differential rf mems spst switch. Microcantilever based rf mems switch for wireless communication. Multiphysics softwares benchmark on ansys comsol applied for. The mechanical response of rf mems polysilicon bridge structure is studied by using comsol multiphysics and fem simulations. Bora, electromechanical modeling and simulation of rf mems switches 2008.
This paper presents the calculation model of capacitive rfmems switch for the isolation and insertion loss, and then adopts cst software to simulate microwave performances. An overview of rf mems switches free download as powerpoint presentation. Rf mems switches offer significant benefits and may be incorporated into many communication devices. This post explores how to analyze the displacement and capacitance in an rf mems switch modeled with comsol multiphysics and the rf. Jun 15, 2015 for space applications, vibration considerations are important, because devices are subjected to large vibrations in the launch process fig. For reliable ohmic switch, it is mandatory to select the appropriate contact material for switch. They are offered in standard surfacemount space saving lfcsp plastic packages. The elastic cantilever beam is one of the elementary structures used in mems designs. Think of rf mems as better switches, better variable capacitors. Transient simulation of the closing of a mems switch with air gap modeled by fluid6 elements nicolas lorphelin. The solid objects can experience forces that will lead to deformation or movement. Apr 02, 2012 donate and download files in full hd here.
You are also more than welcome to send off a quick question to us and find out more. This paper reports on the simulation and analysis of ohmic spdt single pole double throw switch for telecommunication application. The total area on a printed circuit board for a wireless phone is often dominated by passive components. The major part of this chapter is committed to the comparison of the rf mems switches with state of the art solid state. Rf mems switch is designed and simulated in comsol multiphysics, finite element analysis fem tool. The library includes models from rf and microwave engineering, optics and photonics, tutorial models for education, and benchmark models for verification and validation of the. To test your mems devices performance and reliability before manufacturing, you can simulate your design using multiphysics software. Test out how it can work for you by attending a free handson workshop where a complimentary trial of comsol multiphysics and its modules will be made available for you.
The design is based on the series configuration consisting of two cantilever type switches. Comparative study of perforated rf mems switch sciencedirect. Comsol is the perfect tool for simulating mems and piezoelectric devices and applications. Introduction the rf modules model library describes th e interfaces and their different features through tutorial and benchmark examples fo r the different formulations.
Most of the following steps apply on other models 2. The book in your hands, the rf module model library, provides details about a large. Electrical electromechanical effects what are electromechanical effects. What you need to know structure and usage of omron mems switch 2smes01. Uk users conference, november 9th 2011, gaydon, warwickshire 77 g 0 g 1 off state on state con coff g0 g1 capacitive switch with air gap. Design of mems pressure sensors using comsol multiphysics comsol multiphysics is a powerful tool for modeling and solving all kinds of scientific and engineering pressure sensors. Damage growth induced evolution of contact resistance of an rf mems switch design and analysis of rf mems switches for phased. Multiphysics softwares benchmark on ansys comsol applied for rf mems switches packaging simulations.
In this appendix, we show how to do the following using comsol step by step. Mems is written as micro electro mechanical systems, it is the technology of very small devices that. Comsol multiphysics software has been used for simulation of mems switches. Multiphysics users guide or the comsol multiphysics quick start manual. It promises better properties over the electromechanical and semiconductor switches. This tutorial demonstrates how to set up a simple static structural analysis. If you work with microelectromechanical systems mems, integrating the various physics is a key concern. Introduction to rf mems switch working and its applications. The proposed switch has the design with nonuniform meanders and dielectric material silicon nitrate si3n4. Menlo micro has announced that its new digitalmicro switch dms technology platform, demoed in june 2018, has moved from research and development into production at pureplay mems foundry silicon microsystems.
Electromechanical effects arise due to the interaction between electromagnetic fields and solid, elastic structures or rigid bodies. The device was comprised of a fixedfree polysilicon microcantilever beam with electrostatic actuation and capacitive sensing. During the fabrication of piezoelectric rf mems switches and resonators, an aln layer must be patterned into an appropriate geometry. With comsol, it is also possible to observe the effects of temperature on the capacitance value. This rf mems switch is designed and simulated using finite element method fem tool. The company is now producing samples of its new microelectromechanical mems switches on an 8inch wafer manufacturing line and. Crack in single crystal silicon support beams caused by vibrations from a launch test rf mems limitations rf mems basic 27. In this study, the key material indices considered for mems capacitive switch are. Use of comsol multiphysics for automated electrostatic. The effects that need to be taken into account are heat transfer, transport of water vapor, and fluid flow. Comsol multiphysics based on finite element method.
Comparative study of perforated rf mems switch cyberleninka. This paper represents comparative study of perforated rf mems switch. Comsol multiphysics, finite element analysis fem tool. Comsol multiphysics offer physics controlled mesh depending. The structure contains a coplanar waveguide, a big suspended membrane, four folded beams to support the membrane and four straight beams to provide the bias voltage.
A comprehensive study on rf mems switch article pdf available in microsystem technologies 2012 august 2014 with 3,218 reads how we measure reads. The rf mems switches are frequently used in microwave and radio frequency communication devices, such as transmitters and receivers, mode selection switch, antenna switch, etc. Singh 5 proposed the rf mems switch based on seriesshunt configuration, both. The switch closing time depends on the actuation voltage and the opening time depends on the mechanical properties of the switch.
Nguyen2 1radiation laboratory and 2center for microsystems department of electrical engineering and computer science university of michigan ann arbor, michigan 481092122 usa abstract lowloss microwave microelectromechanical systems. Rf mems have in general seen a remarkable growth in the past two decades due to the immense potentials in defense and commercial applications. Mems microphones target all audio applications where small size, high sound quality, reliability and. May 23, 2014 the rf mems switches are frequently used in microwave and radio frequency communication devices, such as transmitters and receivers, mode selection switch, antenna switch, etc. Mems switches i will include mems micro electromechanical systems switches in.
An automated design tool using comsol multiphysics 3. I have a shunt switch simulated under coventor shows pull in voltage of 5v. I referred to the tutorial given in mems module for resonator pull in voltage. This work presents the study of spiral rf mems switch which has low actuation voltage due to spiral structure. The paper provides path forwards in reduction of actuation. Analog devices rf mems switches offer excellent reliability with superior precision and rf performance from 0 hz dc to 14 ghz. I referred to the tutorial given in mems module for resonator pull in voltage calculation and tried to simulate a switch. Jun 16, 2015 this paper presents the design, optimization and simulation of a radio frequency rf microelectromechanical system mems switch. The wet surface feature is used to implement the source term for the water vapor and to. Electromechanical effects can be placed into various.
I am new to comsol, does anyone know how to simulate rf mems switch in comsol. Mar 22, 2018 the switch closing time depends on the actuation voltage and the opening time depends on the mechanical properties of the switch. Comsol can compute propagation constants, impedance, sparameters comsol also solves the timeharmonic transmission line equation for the electric potential for electromagnetic wave propagation along onedimensional transmission lines. The capacitive rfmems switch is electrostatically actuated. Comparative study of cantilever rf mems switch sciencedirect. A comparative study is performed by varying the gaps from 3 to 2. Furthermore, this example may also be defined and modeled using components. Rf mems basics this chapter provides the basic introduction to rf mems switches.
This tutorial article provides an overview of switching technologies commonly. A radiofrequency microelectromechanical system rfmems is a microelectromechanical system with electronic components comprising moving submillimetersized parts that provide radiofrequency rf functionality. Rf mems switches have grown at a very fast rate and many applications in. Piezoelectric devices and rf mems available in the mems module, structural mechanics module, and acoustics module mix dielectric, conductive, structural, and. Mems switch simulation in microwave office tutorials.
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