Abstract—The resonance and nonlinear dynamical properties of micromechanical structures have been harnessed to demonstrate an impacting micromechanical switch with substantially higher switching speed, better reliability (even under hot switching), and lower actuation voltage, all by substantial factors, over conventional RF MEMS switches. The particular resoswitch implementation demonstrated in this work comprises a wine-glass mode disk resonator, driven hard via a 2.5V amplitude ac voltage at its 61-MHz resonance frequency so that it impacts electrodes along an orthogonal switch axis, thereby closing a switch connecting a signal through switch axis electrodes. The 61-MHz operating frequency corresponds to a switching period of 16ns with an effective rise time of ~4ns, which is more than 50 times faster than the μs-range switching speeds of the fastest conventional (nonresonant) RF MEMS switches. Furthermore, with the signal on

Abstract — This paper describes an integration scheme for RF energy harvesting. The scheme includes a resonant voltage boosting network, which provides high amplitude swing from a small signal; and a rectifier that produces DC voltage. Design issues are addressed. Testing circuits are implemented in a Silicon-on-Glass technology. Simulation results show that a DC voltage of 0.8 V can be achieved at-20dBm input energy level at 868.3 MHz ISM band. This would correspond to a potential working distance of 10 meters.

Abstract- A mechanical voltage pump was designed in a single mask SOI process. Theoretical and practical analyses of the operation of the mechanical voltage pump are presented. A design is proposed and possible applications of this design are discussed. Lastly, a comprehensive test structure array was designed. I.

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An approach with the potential for building large low power high performance crossbar networks is presented. Thin film polysilicon MEMS devices are developed to provide crosspoints. These devices are vertically moving plates that serve as variable capacitors. Addressing of large arrays using 2n rather than n-squared lines despite no active circuitry on the MEMS chips is facilitated by bistable device operation. Derivations of equations for bistable device operation are presented. Low power operation is possible as the devices are electrostatically controlled and are stationary except during reconfiguration. Early devices are fabricated using the MUMPS process. The bistability and array addressability properties are demonstrated. The substrate effect on device operation is measured and modeled; methods for utilizing the substrate effect to tune device operation are presented. Later devices are fabricated using the SUMMiT process. Changes in the SUMMiT design rules to increase allowable vertical motion range are proposed and designs using them fabri-cated. S-parameter characteristics of devices in both ‘on’ and ‘off’ states are measured. Addition of metallization after chip fabrication and release is necessary to lower the resistance of interconnect. A self masking method for applying this metallization allowing for decreased resistance at line crossings is proposed. This method is tested using each of sputtering and evaporation as the deposition technique for a gold and adhesion layer stack. Effectiveness of the method with each technique is evaluated. Chips suitable for providing high voltage control for large MEMS arrays are fabricated in a 2um feature size CMOS process. Architectures suitable for building large crossbars employing variable capacitor arrays are discussed. Optimization of hybrid CMOS/MEMS Clos arrays on the basis of criteria other than minimization of crosspoints is discussed. Array sizings to provide 192*192 and 256*256 cross-bars are presented, and software examples for sizing and controlling Clos net-works are provided. Evaluation of the suitability of the MEMS devices developed for use as digital or broadband crosspoints is evaluated, and poten-tial future directions are proposed.

Abstract—A new charge-pump circuit with the controllable body voltage is proposed. By adjusting the body voltage, the back bias effect is removed and the threshold voltage of the MOSFET used as a switch is kept constant. With no threshold voltage increase, higher output voltage than the conventional charge pump can be obtained in the proposed charge pump. With two auxiliary MOSFET’s used to update the body voltage, the proposed charge pump shows compatible performance of the ideal diode charge pump. Index Terms—Auxiliary MOSFET, body effect, charge pump, threshold voltage.

Abstract—This paper presents an energy-efficient chemical sensor system that uses carbon nanotubes (CNT) as the sensing medium. The room-temperature operation of CNT sensors eliminates the need for micro hot-plate arrays, which enables the low energy operation of the system. An array of redundant CNT sensors overcomes the reliability issues incurred by the CNT process variation. The sensor interface chip is designed to accomodate a 16-bit dynamic range by adaptively controlling an 8-bit DAC and a 10-bit ADC. A discrete optimization methodology determines the dynamic range of the DAC and the ADC to minimize the energy consumption of the system. A simple calibration technique using off-chip reference resistors reduces the DAC non-linearity. The sensor interface chip is designed in a 0.18- m CMOS process and consumes, at maximum, 32 W at 1.83 kS/s conversion rate. The designed interface achieves 1.34 % measurement accuracy across the 10 k –9 M range. The functionality of the full system, including CNT sensors, has been successfully demonstrated. Index Terms—Carbon nanotube (CNT), chemical sensor system, low power, sensor interface. I.

This paper studies the principle of a voltage step-up converter based on a micromachined variable parallel-plate capacitor in combination with an electrostatic actuator. Electrical equivalent circuit and system-level SIMULINK models have been developed. An analysis of design parameters serves as a starting point for a novel prototype implementation. Possible areas of application are self-powered, standalone sensing systems, space applications and any kind of electrostatic or piezoelectric microsystem in general. Key Words: Electromechanical voltage conversion, electrostatic microstructures, MEMS modelling