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. This tutorial article provides an overview of switching technologies commonly. An overview of rf mems switches free download as powerpoint presentation. Design and of analysis of spdt ohmic rf mems switch. Quick intro to modeling rf and microwave heating comsol blog. Analog devices rf mems switches offer excellent reliability with superior precision and rf performance from 0 hz dc to 14 ghz. Design, simulation and a comparative study of square, rectangular. Rf mems switches offer significant benefits and may be incorporated into many communication devices.
A novel design of cantilever rf mems series switch iosr journal. The proposed switch has the design with nonuniform meanders and dielectric material silicon nitrate si3n4. As there are variety of materials available to design engineer, a proper technique to select the best possible material is needed. Here it is again, serving as a quick intro to modeling rf and microwave heating. 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. Rf mems basics this chapter provides the basic introduction to rf mems switches. The electromechanical and electromagnetic analysis of the switch has been done using comsol fem and hfss tools. Electrical electromechanical effects what are electromechanical effects. A radially polarized piezoelectric tube is simulated, with two sets of boundary conditions. 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. The simulation results show that return loss can reach21.
How to calculate the pullin voltage of rf mems switch in. Comparative study of cantilever rf mems switch sciencedirect. Capacitive sensor design using comsol provides the user with a wide variety of tools. Typical examples coaxial cable optical fibers and waveguides waveguides and transmission lines z. Rf functionality can be implemented using a variety of rf technologies. A comparative study is performed by varying the gaps from 3 to 2. Understanding switch behavior and characteristics is important for designers. Singh 5 proposed the rf mems switch based on seriesshunt configuration, both. 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. I am new to comsol, does anyone know how to simulate rf mems switch in comsol.
Electrostatically actuated cantilever on comsol youtube. Comsol multiphysics offer physics controlled mesh depending. As i am very new to comsol multiphysics, its very difficult for me to find the procedure for it. This post explores how to analyze the displacement and capacitance in an rf mems switch modeled with comsol multiphysics and the rf. The switch is a capacitive type, which is actuated by an electrostatic force. An automated design tool using comsol multiphysics 3. However, i keep getting errors indication lack of convergence and. Comsol multiphysics based on finite element method. Mechanical systems are switches and variable capacitors, which are used in the front. For reliable ohmic switch, it is mandatory to select the appropriate contact material for switch. Modeling method of finite element modeler and electromagnetic. Transient simulation of the closing of a mems switch with.
Multiphysics design optimization of rfmems switch using. The applications of such rf mems switches in reconfigurable antennas were. Comparative study of perforated rf mems switch sciencedirect. In the comsol multiphysics software any number of physics can be combined in one and the same simulation. Design and simulation of rf mems shunt capacitive switch. Mems switch simulation in microwave office tutorials. The elastic cantilever beam is one of the elementary structures used in mems designs. I referred to the tutorial given in mems module for resonator pull in voltage. Besides rf mems technology, iiiv compound semiconductor gaas, gan, inp, insb, ferrite, ferroelectric.
Damage growth induced evolution of contact resistance of an rf mems switch design and analysis of rf mems switches for phased. With comsol, it is also possible to observe the effects of temperature on the capacitance value. 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. It promises better properties over the electromechanical and semiconductor switches. 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. Electromechanical effects can be placed into various.
They are offered in standard surfacemount space saving lfcsp plastic packages. This archived webinar shows you that by designing mems devices with numerical simulation, you can achieve the highest possible performance. This stepbystep instructional video shows you how the electromechanics interface in comsol multiphysics couples and solves mechanical and electrical problems. Review all of the rf module updates in further detail below. Despite its simplicity, and the fact that very few engineers would run a structural analysis before trying to turn.
If you work with microelectromechanical systems mems, integrating the various physics is a key concern. Multiphysics modeling of mems devices november 20 executive summary power is increased with dedicated tools. An explanation on how to model with a programming language is available in yet another book, the comsol multiphysics scripting guide. How to model electromechanics in comsol multiphysics. 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. 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. To test your mems devices performance and reliability before manufacturing, you can simulate your design using multiphysics software. 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. These interactions may be time invariant, time harmonic, or time varying. Electromechanical effects arise due to the interaction between electromagnetic fields and solid, elastic structures or rigid bodies. I sheared for you a model of rf mems switch in comsol via pdf.
Electromagnetics modeling in comsol multiphysics the acdc and rf modules. The switch closing time depends on the actuation voltage and the opening time depends on the mechanical properties of the switch. I need some tutorials on mems switch simulation in microwave office. Tutorial on comsol multiphysics platform comsol is a multiphysics platform, which will be used to do all your simulations. Comsol, comsol desktop, comsol multiphysics, and livelink are registered trademarks or trade. The effects that need to be taken into account are heat transfer, transport of water vapor, and fluid flow. The analysis is exemplified on a combination wrench during the application of torque on a bolt. The simulation is done using comsol multiphysics software. Microcantilever based rf mems switch for wireless communication. In this appendix, we show how to do the following using comsol step by step. The first case illustrates the inverse piezoelectric effect, and the second case shows the direct piezoelectric effect.
Jun 16, 2015 this paper presents the design, optimization and simulation of a radio frequency rf microelectromechanical system mems switch. What you need to know structure and usage of omron mems switch 2smes01. The device was comprised of a fixedfree polysilicon microcantilever beam with electrostatic actuation and capacitive sensing. It also provides a quick introduction to creating applications using the application builder. Electromagnetics modeling in comsol rf module highfrequency modeling. The company is now producing samples of its new microelectromechanical mems switches on an 8inch wafer manufacturing line and. 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. Use of comsol multiphysics for automated electrostatic mems.
I referred to the tutorial given in mems module for resonator pull in voltage calculation and tried to simulate a switch. The major part of this chapter is committed to the comparison of the rf mems switches with state of the art solid state. This paper presents, the design and simulation of rf mems shunt capacitive switch. The structure of the switch consists of a cpw coplanar waveguides transmission lines and a suspended membrane. The result of rf performance reduces the bucking effect and eliminates the problem of stiction. Transient simulation of the closing of a mems switch with air gap modeled by fluid6 elements nicolas lorphelin.
Jun 15, 2015 for space applications, vibration considerations are important, because devices are subjected to large vibrations in the launch process fig. Three primary performance indices, pullin voltage, rf loss, and thermal residual stress, are used to obtain. Rf mems switch is designed and simulated in comsol multiphysics, finite element analysis fem tool. Radiofrequency microelectromechanical system wikipedia. 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. Mems is written as micro electro mechanical systems, it is the technology of very small devices that. This model analyzes an rf mems switch consisting of a thin micromechanical bridge suspended over a dielectric layer. This paper presents a novel design of a rf mems switch. Most of the following steps apply on other models 2. This rf mems switch is designed and simulated using finite element method fem tool. You are also more than welcome to send off a quick question to us and find out more. This work presents the study of spiral rf mems switch which has low actuation voltage due to spiral structure. Piezoelectric pressure sensor is also designed with circular radius of 180. 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.
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. Fabrication and modeling of piezoelectric rf mems resonators. Geometry of the rf mems switch as modeled in comsol multiphysics together with the mems module. Apr 02, 2012 donate and download files in full hd here. However, photoresistive polymers, typically used for such patterning, are susceptible to the chlorinebased etchants used to pattern aln. The book in your hands, the rf module model library, provides details about a large.
These switches are the unambiguous micro mechanical switches that are intended to operate at rf to mm wave frequencies, which mean 0. Basic concepts and applications with matlab, maple, and comsol, 3 rd edition darrell w. I tried few examples to calculate rf mems pullin voltage, but many a times. Crack in single crystal silicon support beams caused by vibrations from a launch test rf mems limitations rf mems basic 27. In a mems based rf switch cantilever beam is an element that is fixed at one end and free. This paper represents comparative study of perforated rf mems switch. Modelling of different mems pressure sensors using comsol. Electromechanical modeling and simulation of rf mems switches. 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. Bill laumeister, strategic applications engineer oct 04, 2012 abstract. 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. 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. The proposed design consist of mechanical structure with microcantilever beam and capacitive contact type.
By creating an accurate model in comsol multiphysics, you will see how the electrical, thermal, structural, and fluid components interact with each other. How to calculate the pullin voltage of rf mems switch in comsol. Design of low actuation voltage rf mems switch sergio p. Furthermore, this example may also be defined and modeled using components. The number of uses for microelectromechanical systems mems is growingthey allow us to. This paper reports on the simulation and analysis of ohmic spdt single pole double throw switch for telecommunication application. Multiphysics users guide or the comsol multiphysics quick start manual. Modeling mems and piezoelectric devices comsol multiphysics. I have been trying to find out the pull in voltage of a very basic cantilever based mems switch. The mechanical response of rf mems polysilicon bridge structure is studied by using comsol multiphysics and fem simulations. A highpower differential rf mems spst switch a highpower differential rf mems spst switch. Furthermore, this example may also be defined and modeled using components from the following product combinations.
This tutorial shows how to couple three physics interfaces to model evaporative cooling. Multiphysics softwares benchmark on ansys comsol applied for rf mems switches packaging simulations. In a switch like this, the bridge responds to an applied electric potential and voltage by pulling down on the film. Mems switches i will include mems micro electromechanical systems switches in. This tutorial demonstrates how to set up a simple static structural analysis.
Rf mems for wireless communications imems01 short course so many passive components. Introduction to rf mems switch working and its applications. Think of rf mems as better switches, better variable capacitors. 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. 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. Rf mems have in general seen a remarkable growth in the past two decades due to the immense potentials in defense and commercial applications. Piezoelectric devices and rf mems available in the mems module, structural mechanics module, and acoustics module mix dielectric, conductive, structural, and. Chapter 6 contact studies for reliable ohmic switch. Finite element method fem tools are very helpful to design and simulate the rf mems switch. The solid objects can experience forces that will lead to deformation or movement.
Introduction the rf modules model library describes th e interfaces and their different features through tutorial and benchmark examples fo r the different formulations. In this study, the key material indices considered for mems capacitive switch are. Use of comsol multiphysics for automated electrostatic. Bora, electromechanical modeling and simulation of rf mems switches 2008. 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. Since the switch is symmetrical, its only necessary to model one quadrant of the geometry.
The capacitive rfmems switch is electrostatically actuated. Comparative study of perforated rf mems switch cyberleninka. The wet surface feature is used to implement the source term for the water vapor and to. 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. 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. I have a shunt switch simulated under coventor shows pull in voltage of 5v. Comsol multiphysics software has been used for simulation of mems switches. We first start with an example on a very simple electrostatic actuated rf mems switch. The design is based on the series configuration consisting of two cantilever type switches. In this model i make an accurate modeling for electrostatically actuated cantilever on comsol to study its. 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.
Multiphysics softwares benchmark on ansys comsol applied for. Mar 30, 2016 this paper presents a new rf mems capacitive shunt switch with low voltage, low loss and high isolation for kband applications. The total area on a printed circuit board for a wireless phone is often dominated by passive components. The application gallery features comsol multiphysics. This paper mainly engrossed on improving performance and reliability of rf mems switch. 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 is the perfect tool for simulating mems and piezoelectric devices and applications. The paper provides path forwards in reduction of actuation. During the fabrication of piezoelectric rf mems switches and resonators, an aln layer must be patterned into an appropriate geometry. They require only a lowvoltage, lowcurrent power supply and have a fully independent parallel logic control interface. Different beam materials such as gold, aluminum, and platinum are used to.
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