Radio frequency microelectro mechanical systems rf mems are a technology that offers low insertion loss. Despite these benefits, rf mems switches are not yet seen in. In case the transmitting antenna is blocked by a hand or head, the smartphone will swap the transmit signal with a transfer switch. Rf mems switches and integrated switching circuits. Rf functionality can be implemented using a variety of rf technologies. Jan 07, 2014 lets take a look at how you can use comsol multiphysics to simulate an rf mems switch. The isolation of the newer design remains similar to the earlier. Introduction recent demonstrations of microscale highq passive components that utilize microelectromechanical systems mems technology. An overview of rf mems switches free download as powerpoint presentation. 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.
Incorporating rf mems into smartphone antennas yields tunable antennas that work efficiently across one or two frequency bands at a time. The most immediate application will be in aerospace, defense, and highcost commercial applications, as their performance advantages are required and the high packaging cost isnt prohibitive in. This model analyzes an rf mems switch consisting of a thin micromechanical bridge suspended over a dielectric layer. So why didnt rf mems switches take the world by storm years ago. The rf mems switch model, available in the comsol model gallery, shows how to simulate and analyze the contact forces and capacitance changes that occur during operation of the switch. Low cost rf mems switches using lcp substrate guoan wang, dane thompson, emmanouil m. Material selection and parameter characterization for rf mems switches 8 power given their larger contact area 5. Rf mems switches and integrated switching circuits springerlink. Rfmems switches with aln dielectric and their applications. Originally developed for ges internal business units and later spun out for high volume commercial opportunities through menlo microsystems, ge research metal mems combines the great performance of mems rf switches with the integration density of thin film fused silica. 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.
A complete platform for rf switch and varactor design. Rf mems switches, and at the same time, an assess ment of their potential applications in defense and commercial systems. Some of these antennas will be used to transmit and receive while others are receive only. The major part of this chapter is committed to the comparison of the rf mems switches with state of the art solid state. Lets take a look at how you can use comsol multiphysics to simulate an rf mems switch. Rf mems switches indeed have very good highfrequency performance in terms of low insertion loss, good matching and excellent isolation. Stochastic multiphysics modeling of rf mems switches. Mems switch pdf a novel capacitive rf mems switch with. Milosavljevic abstract an overview of the mems technology development and applications is given in this paper. Chou, john h eck, hanan bar, rishi kant and valluri rao intel corporation, santa clara, ca 95054 abstract it is wellrecognized that mems switches, compared to their more traditional solid state counterparts, have several. Stochastic multiphysics modeling of rf mems switches welcome to the ideals repository.
Rf mems mems devices capable of reconfiguring the rf characteristics of a device. Switches are deemed to be key components among the rf mems, and are used for manifold applications e. These results are about 1030 db higher than those of most solidstate devices. The adgm4 is a wideband, singlepole, fourthrow sp4t switch, fabricated using analog devices, inc. Rf mems radio frequency microelectro mechanical systems offer far superior performance in terms of lower insertion loss and higher isolation, higher q and capacitance ratio, higher frequency performance up to mmwaves, higher power handling and much better linearity than solidstate switches and switched capacitors in the 1100 ghz range. Solidstate rf switches made by diodes orand transistors are more reliable and. This part of iec 62047 describes terminology, definition, symbols, test methods that can be used to evaluate and determine the essential ratings and characteristic parameters of.
Fig 1 an rf mems series switch the capacitive switches primarily work by forming a low. Three reconfigurable circuits are presented in this thesis with rf mems devices. Over 10 million scientific documents at your fingertips. Rf mems to enhance telecommunications olivier millet, phd. Rf mems devices and their applications in reconfigurable. Both series and shunt mems switches have been considered. Design for reliability applied to rfmems devices and circuits. Omrons mems switch has a spdtsingle pole double throw contact configuration. The prior art includes an rf mems frequency tunable fractal antenna for the 0. The rf design and modelling of the switch matrix using fullwave electromagnetic em. Oct 31, 20 this contribution presents an optimization strategy for the mechanical and geometrical characteristics of clampedclamped dielectricless rfmems switches in order to enhance their reliability performances both in terms of switch properties control and longterm actuation behavior. Yufeng jin a, jinwen zhang a, weibin zheng b, yilong hao. This need is expected to increase tremendously in the near future with more applications operating.
Pdf on jan 1, 2011, rekha yadav and others published rf mems switches. The design of a rf mems switch plays an important role and involves multidisciplinary skills such as electrical and mechanical engineering and material science. Mems switches employ microminiaturized mechanical contacts controlled by electrostatic forces to make rf connections. Rfmems switches with aln dielectric and their applications montserrat ferna ndezbolanos badia1, pierre nicole2 and adrian mihai ionescu1 this paper reports on the potential of rfmems technology based on aluminum nitride capacitive dielectric and nickelsuspended membranes to provide rf circuit functions in recon. A radiofrequency microelectromechanical system rfmems is a microelectromechanical system with electronic components comprising moving submillimetersized parts that provide radiofrequency rf functionality. The modifications mainly affect the switch membrane, which is made more robust, and the stopping pillar. Ann approach for modeling of mechanical characteristics of rf mems capacitive switches an overview tomislav ciric1, zlatica marinkovic1, olivera pronicrancic1, vera markovic1, larissa vietzorreck2 abstract rf mems switches are nowadays based on a mature technology and are becoming a common component in. This paper presents an overview of the latest development in rf mems switches. The lifetime of these switches is believed to be adversely affected by charge trapping in the silicon nitride.
Rf mems provides a class of new devices and components which display superior highfrequency. Besides rf mems technology, iiiv compound semiconductor gaas, gan, inp, insb, ferrite, ferroelectric. For instance, various mems based tunable capacitors. Three primary performance indices, pullin voltage, rfloss, and thermal residual stress, are used to obtain. Both of them offer low insertion loss across a very wide frequency range. Radiofrequency microelectromechanical system wikipedia. The key element of the exploited process is the microchem su8 2002 negative photoresist. Tentzeris and john papapolymerou school of electrical and computer engineering georgia institute of technology, atlanta, ga 303320250, usa abstract in this paper, we present an rf mems switch developed on a low cost, flexible liquid crystal. Introduction to rf mems switch working and its applications. Rf mems switch performance and features such as actuation voltage, insertion loss, isolation and ease with cost of fabrication and applications. The polymeric material is widely used in mems device processes because of its excellent.
This technology enables a small form factor, wide rf bandwidth, highly linear, low insertion loss switch that is operational from 0 hzdc to 14 ghz, making the adgm4 an ideal solution. The utilization of rf mems helps fulfill the increasing demand for more flexible and functional, lightweight, and lowpowerconsumption wireless systems. Ultrasmall radio frequency and microwave microelectromechanical systems rf mems, such as switches, varactors, and phase shifters, exhibit nearly zero power consumption or loss. Pdf a comprehensive study on rf mems switch researchgate. For this reason, they are being developed intensively by corporations worldwide for use in. With their good rf performances, there is a growing need and interest in rfmems switches for both rf and mmwave applications in the recent years. Mems rf switch pdf a novel capacitive rf mems switch with. The frequency at which they function most efficiently, however, can be changedand rf mems metalcontact switches and variable capacitors are used to make the antennas tunable. The authors report on the recent development of a 2. 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.
In a further section, reliability issues are addressed. Ann approach for modeling of mechanical characteristics of rf. This part of iec 62047 describes terminology, definition, symbols, test methods that can be used to evaluate and determine the essential ratings and characteristic parameters of rf mems switches. Rf mems switches are one of the applications of rf mems y. A special attention is paid to the rf mems switches. Abstractthis paper presents a study of rf mems switch designed to be integrated in tunable filters for applications from wfrequency band to v frequency. Aln based rf mems tunable capacitor with air suspended. The major part of this chapter is committed to the comparison of the rf mems switches with state of the art solid state switches. Think of rf mems as better switches, better variable capacitors. Spst, spdt or xpyt or be used in rf circuits phase shifters, filters, typical configuration. Rf mems switches, with their low loss, high isolation, high linearity, and low power consumption, will bring significant improvements to rf systems.
Rfmems switch design optimization for longterm reliability. Rfmems switches for reconfigurable integrated circuits. Txrx selection, reconfiguration of filters, of phase shifters or of antennas. It is also presented a technique for modeling and design of inductivelytuned mems shunt switch. The rfmems capacitive shunt switches as well as the other mems presented in this article use a common fabrication process developed at the fraunhofer institute of silicon technology isit. Presents rf switches and switching circuit mems devices in a unified. Rf mems have in general seen a remarkable growth in the past two decades due to the immense potentials in defense and commercial applications. Rf mems basics this chapter provides the basic introduction to rf mems switches. For all three environments more complex rfmems based circuits have been designed and characterized. Brown, senior member, ieee invited paper abstract this paper deals with a relatively new area of radiofrequency rf technology based on microelectromechanical systems mems. This advanced technology enables a discriminating capability for high performance integrated rf and millimeter wave assemblies. Hotswitching reliability of rf mems switches rf mems switch reliability is a major concern because of the relatively new technology of the devices.
These switches are the unambiguous micro mechanical switches that are intended to operate at rf to mm wave frequencies, which mean 0. In this paper we present a novel process based on su8 technology for the fabrication of double clamped radio frequency rf microelectromechanical system mems capacitive shunt switches in coplanar configuration. The reliability of the silicon nitride dielectric in capacitive mems switches a thesis in materials science and engineering by abuzer dogan. Nguyen darpamto 3701 north farifax drive, arlington, virginia 222031714. Keywords switches, but further allows the use of metal materials with subrf mems, quality factor, micromechanical circuit, rf front end, resonator, switch, inductor, capacitor 1. Ge research rf mems rf mems capabilities all fused silica stack up with integrated rf mems, passives, tgvs and bga attach.
Rf mems switches fabrication by using su8 technology. Van caekenberge rf mems on the radar, ieee microwave magazine october 2009. Spst, spdt or xpyt or be used in rf circuits phase shifters, filters. The original process includes a combination of thin and thick nickel ni for the suspended membrane and the anchors andor stiffening bars, respectively. Rf mems switches and integrated switching circuits aiqun liu. A comprehensive study on rf mems switch article pdf available in microsystem technologies 2012 august 2014 with 3,218 reads how we measure reads. As there are variety of materials available to design engineer, a proper technique to select the best possible material is needed. Rf mems components that are currently under development in laboratories and industries around the world include switches, tunable capacitors, mems inductor with high q factor 2, film bulk acoustic resonators fbars, and mems resonators and filters 35. Rf mems switches capable of switching over 100 billion cycles. Capacitive switches have been presented by numerous authors 1, 2, and 3 and show excellent life time. The polymeric material is widely used in mems device processes because. Microelectromechanical systems mems stand poised for the next major breakthrough in the silicon. Rf mems switches exhibit attractive performance with. Radiofrequency microelectromechanical systems rf mems are highly miniatur.
Delfmems develops, fabricates and provides rf switches based systems using mems technology mems for radiofrequency systems provide mems based devices for rf systems. There are two types of rf mems switches that have come to the forefront. Figure 1, shows a schematic diagram of these switches. Mems switch pdf mems switch pdf mems switch pdf download. Silicon nitride thin film dielectrics can be used in capacitive radio frequency microelectromechanical systems switches since they provide a low insertion loss, good isolation, and low return loss. Ann approach for modeling of mechanical characteristics of.
Metal contact reliability of rf mems switches qing ma, quan tran, tsungkuan a. This contribution presents an optimization strategy for the mechanical and geometrical characteristics of clampedclamped dielectricless rfmems switches in order to enhance their reliability performances both in terms of switch properties control and longterm actuation behavior. Huikai xie most figures and data in this lecture, unless cited otherwise, were taken from rf mems theory, design and technology by g. In this paper, we shall be discussing capacitive switches only. 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. Jan 14, 2014 incorporating rf mems into smartphone antennas yields tunable antennas that work efficiently across one or two frequency bands at a time.
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