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The paper presents a study oriented to the understanding of the floating electrode role on the charging characteristics of floating electrode RF MEMS capacitive switches. Identical devices with and without floating electrode have been stressed under induced charging mode. Biases of different levels and polarities were applied to the transmission line. Reduced and asymmetric, with respect to the bias polarity, charging effects were obtained on devices with floating electrode compared to the conventional ones. The results contribute towards the conclusion that the use of floating electrode in conjunction with the appropriate actuation polarity may reduce the charging effects and thus improving the device lifetime. © 2015 Elsevier Ltd.

The paper investigates the actuation mechanism in floating electrode microelectromechanical system capacitive switches. It is demonstrated that in the pull-in state, the device operation turns from voltage to current controlled actuation. The current arises from Poole-Frenkel mechanism in the dielectric film and Fowler-Nordheim in the bridge-floating electrode air gap. The pull-out voltage seems to arise from the abrupt decrease of Fowler-Nordheim electric field intensity. This mechanism seems to be responsible for the very small difference with respect to the pull-in voltage. © 2011 American Institute of Physics.

RF Micro-Electro Mechanical Systems (MEMS) have been developed during the last decade with several applications for commercial as well as space and military sub-systems [1-6]. Technological processes encompassing the utilization of typical microelectronic substrates like alumina, GaAs and Silicon have been considered for the realization of micro-switches by surface micromachining. True time delay lines (TTDL), single port multiple throw (SPMT), matrices and phase shifters take benefit from the low insertion loss, all passive and distortion-free environment offered by RF MEMS. Antenna re-configuration through digital phase shifters based on RF MEMS switches are currently studied.

The reliability of RF MEMS switches is typically reduced by charging effects occurring in the dielectrics. The aim of this paper is to discuss these effects, and to propose analytical and equivalent circuit models which account for most of the physical contributions present in the structure. © 2009 Springer-Verlag.

Two different topologies of RF MEMS series ohmic switches (cantilever and clamped - clamped beams) in Coplanar Waveguide (CPW) configuration have been characterized by means of DC, environmental and RF measurements. The devices have been manufactured on High Resistivity (HR) Silicon substrates, as building blocks to be implemented in different Single-Pole 4-Throw (SP4T), Double-Pole Double-Throw (DPDT) configurations and then integrated in LTCC technology for the realization of Large Order Clos 3D networks.

The charging of the dielectric used for the actuation in microelectromechanical system (MEMS) devices is one of the major failure sources for switches based on this technology. For this reason, a better understanding of such an effect is vital to improve the reliability for both ground and space applications. In this paper, the expected response of MEMS switches to unipolar and bipolar dc actuation voltages has been measured and modeled. Two configurations of MEMS switches, namely, an Ohmic series and a shunt capacitive one designed for microwave applications, have been studied as a test vehicle for charging effects related to the dc actuation pads. The recorded data have been interpreted mainly through the Poole-Frenkel effect due to charge injection when a high voltage is applied to the dielectric layer. Metal-Insulator-Metal (MIM) structures have been also considered as a complementary information for the response of the dielectric material. © 2009 American Institute of Physics.

RF MEMS Matrices have been implemented within an ESA-ESTEC supported consortium to release the feasibility of sub-elements useful for more complicated structures involving several switches, to be implemented for satellite communications. At this stage, 2 x 2 Matrices have been developed, by using series ohmic switches for I/O interconnections and shunt capacitive switches to improve the isolation response. The realised configurations have been tested in the frequency range (0.045 - 40) GHz. Insertion Losses as low as -1.5 dB and Return Losses around -40 dB have been measured at 20 GHz for the 90 degrees path.

We propose the design of a reconfigurable impedance matching network for the lower RF frequency band, based on a developed RF-MEMS technology. The circuit is composed of RF-MEMS ohmic relays, metal-insulator-metal (MIM) capacitors and suspended spiral inductors, all integrated on a high resistivity Silicon substrate. The presented circuit is well-suited for all applications requiring adaptive impedance matching between two in principle unknown cascaded RF-circuits. The fabrication and testing of a monolithic integrated prototype in RF-MEMS technology from ITC-irst is currently underway., Comment: Submitted on behalf of EDA Publishing Association (http://irevues.inist.fr/EDA-Publishing)

The paper presents a technology based on bulk and surface micromachining to manufacture lumped elements (capacitors and inductors) based low pass and high pass filter structures, having membrane supported spiral inductors. Test low pass and high pass filter structures are manufactured using silicon as well as GaAs micromachining. These technologies will be also useful in the manufacturing of reconfigurable membrane supported filters for millimeter wave applications.