Like pin diodes, the fet switch can be configured in series with transmission line drain. Rfmems switches for reconfigurable integrated circuits abstract. The two main types of mems switches will be discussed and then compared with semiconductor devices using the. Emems switches capacitive shunt switches dccontact shunt switches dccontact series switches 3162005 eel6935 advanced mems spring 2005 instructor. This page describes rf mems basics with applications and rf mems switch manufacturers. A18a4b0055 nanosystems at the edge at nus, singapore. Besides rf mems technology, iiiv compound semiconductor gaas, gan, inp, insb, ferrite, ferroelectric. Rf mems switches and integrated switching circuits builds on the extensive body of literature that exists in research papers on analytical and numerical modeling and design based on rf mems switches and micromachined switching circuits, and presents a unified framework of coverage.
An equivalent circuit model for the single beam rf mems switch is shown in. Mems are ic devices which will have both electrical as well as mechanical components. Mems switches can be categorized into metal contacting. Since the usage of rf mems devices in modern ic integrated circuits and rf. Relatively low switching speed, power handling, and highvoltage drive are some of the key issues in mems switches. Memsnems switch, piezoelectric micromachined ultrasonic transducer. Rf mems switches offer many advantages over solidstate switches, in terms of low loss, high isolation, low power consumption and high linearity 1. Denhoff1 1institute for microstructural sciences, national research council, ottawa, canada k1a 0r6 2electrical and computer engineering department, university of waterloo, waterloo, canada, n2l 3g1 dated. It is the short form of micro electro mechanical systems. Modeling and design of high speed switches and high capacitance ratio switches are presented.
Design, modeling, and fabrication of an integrated micromechanical switch for. Switching speed analysis of rf mems switch duepublico 2. Ann model of rf mems lateral spdt switches for millimeter wave. Rf mems provides a class of new devices and components which display superior highfrequency performance relative to conventional usually semiconductor. Rf mems dpdt switch intellisense total mems solutions. Abstractthis paper proposes a mems relay circuit by paralleling an. In this paper we report on recent developments of high power rf mems switches using a matrix or array of switching elements as shown in fig. Rf mems switches and integrated switching circuits mems reference shelf book 5 kindle edition by aiqun liu. Advantage of rf mems devices it is difficult to discuss the advantages of all of the. Nanoelectromechanical nem relay devices and technology.
There are other reported rf mems devices from france. Ultrareliable mechanical switches capable of extended life up to 10million switch cycles. The rfmems switches, especially those with wide cantilever designs, use small diameter holes 210 m in the beam to speed up the release etch while allowing easier sacrificial layer removal. Mems switches with thickfilm multilayer substrates. A comparison between rf mems switches and semiconductor switches p.
This paper mainly investigates the influence of the shape of the rf mems switches on the actuation voltage and the method to reduce the squeeze film damping effect by. Novel multiport rf mems rtype switches and their integration in the form of redundancy switch matrices have been also presented. Mems reference shelf mems reference shelf editorinchief stephen d. Micro electromechanical systems, also known as mems, is an emerging technology, which is finding its way into a number of applications, such as gyroscopes, sensors, digital imaging and mobile communications. Huikai xie most figures and data in this lecture, unless cited otherwise, were taken from rf mems theory, design and technology by g. Rf functionality can be implemented using a variety of rf technologies.
These rfmems switches are used to change spiral overall arm length for di. Design, analysis and comparison of various mems switches for. With a twophase stepper motor and the circuit in figure 6, we can drive the stepper with the appropriate power levels. Ultra low actuation voltage rf mems switch micro and nano. Design, analysis and comparison of various mems switches for reconfigurable planar antenna 26 b c d figure 1 a 2d layout with dimension of beam b 3d layout of design1 capacitive switch. 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.
The book presents the design and fabrication of rf mems switches and switch circuits. And we will add some additional comments about the present research activity of rf mems devices and about monolithic integration of such devices with circuits. Mems switches escell excell excell exell poor good advantages. Brown, senior member, ieee invited paper abstract this paper deals with a relatively new area of radiofrequency rf technology based on microelectromechanical systems mems. External wire coils can motivate the mems, or coils can be integrated into the mems structure. Electroplated rf mems capacitive switches request pdf. Monolithically integrated micromachined rf mems capacitive. It is also presented a technique for modeling and design of inductivelytuned mems shunt switch. The microelectromechanical systems mems is the integration of. Microsystems employing switches were also reported. These are more complicated than the switch you use to turn on a light. The operating theory, operating characteristics, and specifications of the redrock switch are compared and contrasted with other popular magnetic switching. There are two types of forces used for the actuation of rf mems switches.
Despite the advantages in the design of rf mems switches designing a low actuation voltage rf mems switch is still a challenging task. Design, analysis and comparison of various mems switches. Mems, fet and pin rf switching devices and circuits for. The lateral dccontact switch can be easily integrated into the switching matrix. Rf mems switch performance and features such as actuation voltage, insertion loss, isolation and ease with cost of fabrication and applications are compared and. Rf mems switches and integrated switching circuits hard contact materials, large contact area and hermetic package. Mems switches for millimeterwave application as an example of rf mems devices.
Equivalent circuit of design1 in c up position and d down position. Systems mems switch implemented on a coplanar waveguide. Request pdf electroplated rf mems capacitive switches rf. Rfmems switches for reconfigurable integrated circuits article pdf available in ieee transactions on microwave theory and techniques 4611. Design of a high power mems relay with zero voltage switching.
A comparison between rf mems switches and semiconductor switches. The thicker the transmission line is, the lower the insertion loss of. The rf mems switches, especially those with wide cantilever designs, use small diameter holes 210 m in the beam to speed up the release etch while allowing easier sacrificial layer removal. With the use of rf mems switches, it is possible to meet all the criteria in a small space envelope. One disadvantage of the thyristor for switching circuits is that. May 23, 2014 rf mems switches are micromachined systems that use a mechanical faction in the radio frequency transmission line to attain a short circuit or an open circuit. Engineering electrical engineering and computer sciences. Capacitive switches capacitive switches are key elements in various applications such as tunable capacitors and tunable filters. In this paper we report on recent developments of high power rf mems switches using a matrix or array of switching elements. Although semiconductor switches such as fets or pin diodes are widely used in millimeter wave integrated circuits mmics and microwave circuits, many researches have been performed to develop micromechanical switches for mechanically switching microwave signals.
Highperformance and lowcost capacitive switches for rf. Thyristors are able to withstand very high reverse breakdown voltage and are also capable of carrying high current. Electrostatic mems switches require a relatively high actuation voltage to drive the movable part. Rf mems switch with high isolation at high frequencies, a. Generally, rf mems switches are based on designs that employ electrostatic actuation. Milosavljevic abstract an overview of the mems technology development and applications is given in this paper. Spdt mems switches that have also utilized a dual switch design with quarter wavelength sections need two separate biasing circuits to actuate each device alternatively. There are many application areas possible for microwave. It presents rf mems capacitive switches and mems tunable filter first ever to be produced in norway. Spdt rf mems switch using a single bias voltage and. Introduction micro electromechanical systems mems technology is an evolving technology that. Mechanical switches are too slow and bulky to handle all the processing required to even do something as simple as write an email. The samples are composed of 400 m highresistivity silicon.
These switches are the unambiguous micro mechanical switches that are intended to operate at rf to mm wave frequencies, which mean 0. Development of rf mems switches for high power applications. It also explores the hotswitching reliability of mems switches using different types of input signals. Both series and shunt mems switches have been considered. Solidstate switches with extremely fast switching times. Rfmems activities in europe imperial college london. Rf mems basics rf mems switch manufacturers vendors. A dissertation submitted in partial satisfaction of the. Based on this comparison we will show some fundamental reasons for the advantages that mems switches offer for microwave routing. Aug 11, 2015 rf mems switches mostly employ electrostatic actuation due to low power consumption and short switching time as well as compatibility with electrical circuits and components. There are different approaches in which high power rf mems switches may be developed, such as those based on material improvements 34. Microelectromechanical systems or mems is the integration of mechanical elements, sensors, actuators, and electronics using batchlevel microfabrication technology. Rf mems switches and integrated switching circuits mems.
Basic properties of pin diode and fets in rf switching applications. Integrated reconfigurable radio frontend technology irrft. To overcome this problem, a small size rf mems switch utilizing a moving plate with multiple holes. Rf mems circuits applications of mems switch and tunable capacitor dr. The actuation voltage of the rf mems switch is the most important for compatible with modern electronic control circuits and improve lifetime. A special attention is paid to the rf mems switches. Switching speed is more than sufficient for rf control circuit applications. International journal of microwave and wireless technologies, 2011. Rf mems provides a class of new devices and components which display superior highfrequency. Usb, ethernet, and spi control interfaces available. Mems switches marx v marxism pdf and other components have been very interesting area for research. Rf circuits for aesa using rf mems switches examples phase shifter tline matching network switched filter bank schoenlinner, b. Rf mems switches and integrated switching circuits aiqun liu.
Spdt, dpdt transfer, sp4t, sp6t, sp8t, and sp10t mechanical and solid state rf switches for 50ohm and 75ohm systems spanning dc to 40 ghz. Aug 22, 2014 this paper emphasis on stateoftheart of the earlier until the current trend and demand, principles, design considerations, key performance and fabrication technology of rf mems switch devices developed over the past few years. In fact, just representing a single number requires eight switches. It also presents rf mems capacitive switches, first ever to be produced in norway. These holes also reduce the stiffness of the cantilever as well as the squeeze film damping increasing the switching speed of the mems switch. Mems technology combines high precision and integration of transducers with control electronics in a small footprint. This paper emphasis on stateoftheart of the earlier until the current trend and demand, principles, design considerations, key performance and fabrication technology of rf mems switch devices developed over the past few years. Computers use switches to represent information such as numbers and letters. Reliability study of lowvoltage rf mems switches david becher, richard chan, michael hattendorf, and milton feng high speed integrated circuits group department of electrical and computer engineering, university of illinois 208 n. Radiofrequency microelectromechanical system wikipedia. This paper deals with a relatively new area of radiofrequency rf technology based on microelectro mechanical systems mems. Rf mems switches and integrated switching circuits. Power semiconductor devices first appeared in 1952 with the introduction of the power diode.
Modeling and simulation of various rf mems switches and switch circuits 25. Applications of nonlinearities in rf mems switches and. For the purpose of wireless communication or integrated circuit design. Comparison of existing switches with mems relays characteristic mmr gaas fet pin diode emr pcb emr sma size small very small small medium large resistance 0. Rf mems switches and integrated switching circuits jsts.
Integration of a high performance mmwave packaged rfmems switch technology. Rfmems switches for reconfigurable integrated circuits. In the design presented here, no switching voltage supply is needed since the switching of the signal between ports is controlled by a single bias supply. Mems magnetic motors operate using magnet attraction and repulsion just like bigger motors. Muldavin, rf mems switches and switch circuits, ieee microwave magazine, dec. Pdf rfmems switches for reconfigurable integrated circuits. However, rf mems switches have reliability problems that are linked to rf signal power level. It also explores the hotswitching reli ability of mems switches using different. A radiofrequency microelectromechanical system rfmems is a microelectromechanical system with electronic components comprising moving submillimetersized parts that provide radiofrequency rf functionality. Presents rf switches and switching circuit mems devices in a unified. Finally, it evaluates a possibility for improving the reliability of mems switches using an external circuit. In this brief a new low actuation voltage rf mems switch is presented which can be integrated and controlled with available cmos technologies. Virtually no control circuit power dissipation in either on or off state with proper design, can be capable of broad band and high power switching. A comprehensive study on rf mems switch springerlink.
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