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In this paper, we present a new type of rf MEMS switch with low actuation voltage and high isolation, for high rf power and reliability applications in telecommunication. ‘Symmetric toggle switch’ (STS) is based on push–pull mechanism and utilizes torsion springs and levers, placed symmetrically and transverse to CPW line. The switches designed for 8–14 GHz applications have analytically calculated and FEM simulated actuation voltages in the range of 8–10 V. The simulated insertion loss and isolation for the devices are 0.25 and 35 dB, respectively, at 10 GHz. The fabrication process and preliminary experimental results are also presented.

A measurement system combining vector corrected waveform measurements with active harmonic load-pull extends, for the first time, real-time experimental waveform engineering up to the 30-W power level. The vector correction procedure is presented in this paper. A novel harmonic load-pull approach based on the real-time measurement capability of the system is demonstrated on a 4-W LDMOS device. A 20% increase in maximum output power to 4.7 W without degrading gain and efficiency is realized. Waveform analysis at various drive and load conditions directly identifies nonlinear capacitance effects being a key design issue for the design of highly efficient power amplifier.

Electrostatic actuated radio frequency microelectromechanical systems (RF-MEMS) switches and variable capacitors are susceptible to issues related to RF actuation or even RF pull-in under large-signal regime. This phenomenon is strictly related to the average RF voltage more than power, and the impedance environment of the device should be fully accounted for. We perform for the first time large-signal time-domain measurements to characterize the RF actuation effect on the real-time capacitance value of a suspended membrane-based RF-MEMS varactor, while controlling the load impedance presented to the device with an active load-pull. The dependence of RF-actuation on both real impedance and inductive admittance is directly extracted, giving strong insights on how power handling should be carefully scrutinized against each specific circuit design.

RF-MEMS switches have potential prerogatives better than traditional solid state devices, but the presence of mechanical movement introduces new classes of reliability issues that are not found in traditional devices. In this work we have carried out an extensive electrical characterization in order to identify the dynamic response of RF-MEMS switches driven in different conditions of voltage and actuation time. Furthermore, probably due to their recent introduction to the market, the robustness of MEMS submitted to ESD stresses has been also poorly investigated. We have studied, for the first time to our knowledge, the effects of TLP-ESD events on RF-MEMS switches identifying a very critical ESD sensitivity.

This paper presents a 1.5-2.4 GHz 4-pole tunable filter using the Cavendish Kinetics RF MEMS capacitors. The MEMS capacitors are fabricated and fully packaged using a 0.18 μm CMOS standard process with integrated high voltage drivers and SPI control logic and with reliability in the billions of cycles. The filter results in a power handling of at least 20 dBm, a second and third harmonic generation of

Industrial design constraints coupled with increased frequency coverage required for today's mobile Smart Phone handsets, are making it difficult to develop highly efficient broadband antenna solutions. This paper will show how antenna aperture tuning using a high performance MEMS (microelectromechanical system) Digital Variable Capacitor can improve antenna performance across all frequency bands for 3G and 4G LTE communications.

In this paper we discuss an approach for the implementation of non-linear electromechanical and RF models of complete RF-MEMS devices within a standard circuit simulator, such as Cadence Spectrecopy or Agilent ADStrade. The intrinsic electromechanical core is based on a structural hierarchical model library implemented in VerilogAcopy language. Moreover, a surrounding lumped element network accounting for the electromagnetic RF behaviour of the MEMS device is extracted from S-parameters measured data. The whole nonlinear model network, composed of the intrinsic VerilogAcopy core plus lumped-element parasitics, can be analysed within a radiofrequency circuit simulator schematic. The model is fully validated against electromechanical and RF static and dynamic measurements, showing good agreement between simulations and experimental results. The presented modeling approach can be the basis for the development of complete RF-MEMS design technology libraries, aiming at optimum hierarchical designs of MEMS-enabled RF circuit blocks.

In this work, a new method is presented for the extraction of low order electromechanical models for dynamic nonlinear simulation of radio frequency (RF) microelectromechanical (MEMS) switches, using model order reduction (MOR). The method is based on a separate modeling of the electrical and the mechanical part of the problem, which are coupled at circuit level. The derived reduced order model includes effects of initial stress in the device materials and enables a substantial speed-up of large signal dynamical analysis. The accuracy of the model has been demonstrated by comparing the simulated and measured dynamic response of a fabricated device.

A hierarchical and mixed-domain design approach is implemented within the Cadence/sup /spl reg// simulation framework and applied to an integrated MEMS-CMOS oscillator. Parameters concerning both the electronic circuit description at transistor level and the MEMS structure defined by its topology and dimensions, are available during simulation. This approach can lead to a full optimisation of the complete MEMS-CMOS sub-system, with a view to both electrical and mechanical specifications.

A hierarchical MEMS design library, implemented in SpectreHDL/spl reg/ within the Cadence/spl reg/ simulation framework is applied to the study of distortion phenomena in RF-MEMS capacitive shunt switches. Two-tone mixed-domain transient simulation of the non-actuated switch, operated at high-power, directly shows, for the first time, self-biasing modulation at the tones spacing frequency. Adjacent-channel intermodulation products are observed and quantified, proving that the adopted mixed-domain simulation approach is the key tool for addressing system-level specifications in RF-MEMS design for wireless applications.

Analytical nonlinear model validation through large-signal time-domain characterization has been greatly improved, by establishing a novel link between measurement and simulation. Investigation on a silicon LDMOS device and its nonlinear electro-thermal model positively identifies links between model formulation and amplifier requirements for future telecommunication systems.

A MEMS (microelectromechanical system) test structure for planar stress characterization of the structural layer in a surface micromachining process is presented. The classical rotating needle design has been adopted and enhanced with electrical capacitive transduction of the rotation angle. The main goal is a device suitable for electrical measurements in order to allow in situ and fast in-line automatic testing. Stress extraction is performed through quantized capacitive transduction, leading to improved robustness versus capacitive parasitic effects which typically impair the analog transduction. The methodology is demonstrated through a comparison between electrical measurements and optical inspections on fabricated prototypes based on a gold electroplated structural layer.

A hierarchical MEMS design library, implemented in SpectreHDL® within the Cadence® simulation framework, is applied to the study of distortion phenomen in RF-MEMS capacitive shunt switches. Two-tone mixeddomain transient simulation of the non-actuated switch, operated at high-power, directly shows, for the first time, self-biasing modulation at the tones spacing frequency. Adjacent-channel intermodulation products are observed and quantified, proving that the adopted mixed-domain simulation approach is the key tool for addressing system-level specifications in RF-MEMS design for wireless applications.