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Kazuhiro Hane - One of the best experts on this subject based on the ideXlab platform.

  • Transmission-Width-Tunable Silicon-Photonic Microelectromechanical Ring Resonator
    IEEE Photonics Technology Letters, 2013
    Co-Authors: Mustafa Ordu, Kazuhiro Hane
    Abstract:

    A microring resonator with a transmission-width (Q-factor) tuning mechanism is proposed. The proposed resonator is composed of freestanding 320-nm-wide 340-nm-thick silicon waveguides, two waveguide couplers, and a 30- μm-wide 40- μm-long Comb-Drive Actuator. The transmission width of the microring is tunable by varying the coupling rate of the couplers with the Actuator. The transmission width was varied from 1.42 to 1.61 nm (Q-factor from 1100 to 970) by changing the Actuator voltages from 9 to 11 V.

  • Monolithic micro-fabrication of Si micro-electro-mechanical structure with GaN light emitting diode
    Microsystem Technologies, 2010
    Co-Authors: R. Ito, F. -R. Hu, Mihoko Wakui, Hiroshi Sameshima, Kazuhiro Hane
    Abstract:

    Si micro-electro-mechanical device with GaN light emitting diode (LED) is monolithically fabricated. The GaN-LED layer was grown by molecular beam epitaxy on Si wafer and the basic properties of the LED were tested. The GaN/Si wafer was micromachined using deep reactive ion etching to fabricate Si electrostatic Comb-Drive Actuator. A light distribution variable device with Si Actuator was fabricated from the grown wafer. From those experiments, it is shown that the Combination of the GaN crystal growth on Si wafer and the Si micromachining is valuable for a new kind of optical micro-systems.

  • Driving of micromirror and simultaneous detection of rotation angle using integrated piezoresistive sensor
    TRANSDUCERS and EUROSENSORS '07 - 4th International Conference on Solid-State Sensors Actuators and Microsystems, 2007
    Co-Authors: Minoru Sasaki, Motoki Tabata, Masahiro Tabata, Kazuhiro Hane
    Abstract:

    A piezoresistive rotation angle sensor is integrated in a micromirror Driven by the electrostatic vertical Comb Drive Actuator. The sensor signal is the voltage generated by the shear piezoresistance effect. Driving the electrostatic Actuator, the sensor signal is measured. The sensor signal is confirmed to be proportional to the mirror rotation angle. The hysteresis of the sensor signal is found to be less than that observed under the open-control of the micromirror.

  • XY-Stage for Scanning Media for Optical Data Storage
    IEEE LEOS International Conference on Optical MEMS and Their Applications Conference 2006., 2006
    Co-Authors: M. Sasaki, F. Bono, Kazuhiro Hane
    Abstract:

    XY-stage Driven by the electrostatic Comb-Drive Actuator is fabricated realizing long displacement. The Actuator is fabricated in one layer of silicon-on-insulator (SOI) wafer, and the media plate is in the other layer. The raster scanning of the plate is realized maintaining orthogonal xy-directions. The fast scanning is y-axis. Two 820times950 mum2-size media plates are Driven at the opposite y directions canceling the inertia force. The static maximum displacements are 110 mum (geometrical limit) along x-axis and 90 mum along y-axis. At the resonance, 115 mum (geometrical limit) is obtained along y-axis

  • Three-dimensional SOI-MEMS constructed by buckled bridges and vertical Comb Drive Actuator
    IEEE Journal of Selected Topics in Quantum Electronics, 2004
    Co-Authors: M. Sasaki, D. Briand, W. Noell, N.f. De Rooij, Kazuhiro Hane
    Abstract:

    A new method for realizing three-dimensional structures based on the standard silicon-on-insulator microelectromechanical systems is developed using vertically buckled bridges as structural elements. The vertical displacement, profile of the bridge, and obtainable accuracy of the displacement are examined. Using the lateral dimension control of the bridge and the supporting beams, the vertical positioning is realized based on the planer photolithography. As a demonstration, a vertical Comb Drive Actuator is prepared and its performance is examined.

Gen Hashiguchi - One of the best experts on this subject based on the ideXlab platform.

  • $In Situ$ Measurement of Charging Process in Electret-Based Comb-Drive Actuator and High-Voltage Charging
    Journal of Microelectromechanical Systems, 2015
    Co-Authors: Yasushi Shibata, Tatsuhiko Sugiyama, Hidenori Mimura, Gen Hashiguchi
    Abstract:

    We report in situ measurements of the charging process for an electret-based Comb-Drive Actuator and an experiment on high-voltage charging. The ac current flowing between the Comb-Drive electrodes, which is proportional to the displacement, is monitored during the application of a dc bias voltage at an elevated temperature. As the charge voltage increases, it opposes the applied voltage, causing the current to decrease and become a minimum, which indicates the completion of the charging process. The proposed electret-based method allows voltage-controlled charging in silicon microelectromechanical systems (MEMSs) devices, which offers advantages for commercial MEMS device fabrication. This paper also discusses the importance of high-voltage charging for improving the efficiency of the Actuator as an electrostatic vibration-energy harvesting device. A charging mechanism is proposed to explain the experimental results, and the stability of the movable Comb-Drive electrode against the pull-in effect is discussed. Using the proposed method, a large force factor is obtained, and charging to a voltage of up to 380 V is demonstrated.

  • SiO2 electret induced by potassium ions on a Comb-Drive Actuator
    2012 IEEE 25th International Conference on Micro Electro Mechanical Systems (MEMS), 2012
    Co-Authors: Tatsuhiko Sugiyama, Hiroyuki Fujita, Mitsuru Aoyama, Yasushi Shibata, Masato Suzuki, Takashi Konno, Manabu Ataka, Gen Hashiguchi
    Abstract:

    This paper reports a novel SiO2 electret on Comb-Drive Actuator, which is formed by concise procedure and low cost. The SiO2 electret is generated by doping potassium ions and formed on vertical walls of driving electrodes in a Comb-Drive Actuator. The current generated by the extraneous vibration was observed, so this device is thought to be useful as the vibration power generator.

  • sio2 electret generated by potassium ions on a Comb Drive Actuator
    Applied Physics Express, 2011
    Co-Authors: Tatsuhiko Sugiyama, Hiroyuki Fujita, Mitsuru Aoyama, Yasushi Shibata, Masato Suzuki, Takashi Konno, Manabu Ataka, Gen Hashiguchi
    Abstract:

    Silicon dioxide electret generated by doping potassium ions will be demonstrated by forming it on a Comb-Drive Actuator. The Comb-Drive Actuator made of silicon on an insulator substrate is oxidized with bubbling a stream of KOH solution to form silicon oxide film including potassium ions uniformly on the etched side walls of Comb electrodes. After a bias-temperature procedure at about 900–1000 K and 100 V was applied to the device, we confirmed a 40 V built-in potential difference between the opposing Comb electrodes. The gradual decay of the potential was observed, but 35 V was maintained even after 1 month.

  • analysis of a Comb Drive Actuator taking the depletion layer into consideration
    Ieej Transactions on Sensors and Micromachines, 2010
    Co-Authors: Shinji Ueki, Yuuki Nishimori, Hiroshi Imamoto, Tomohiro Kubota, Masakazu Sugiyama, Seiji Samukawa, Gen Hashiguchi
    Abstract:

    We have analyzed the effect of penetration of the electric field into the semiconductor on the electrical and mechanical characteristics of Comb-Drive Actuators. In this study we found two specific effects due to the depletion layer: (1) the electro-mechanical conversion factor is a function of the depletion layer and becomes smaller than that for the “ideal conductor” assumption, and (2) an additional stiffness appears in the mechanical system. Following the change in the electro-mechanical conversion factor, the resonance peak becomes lower than that of an ideal conductor. These effects are relatively small when the gap between the Comb-fingers and the substrate is of the order of a micrometer. However if the gap is 0.1μm, the electro-mechanical conversion factor decreases by about 2.8%. In this analysis, we have taken only the depletion effect into account; however, for a more complete analysis we should also consider the surface traps induced by unpassivated surface bonds.

  • a multiple degrees of freedom equivalent circuit for a Comb Drive Actuator
    Japanese Journal of Applied Physics, 2009
    Co-Authors: Yuuki Nishimori, Hideta Ooiso, Shunsuke Mochizuki, Nobuyo Fujiwara, Toshiyuki Tsuchiya, Gen Hashiguchi
    Abstract:

    We present an equivalent circuit of a Comb-Drive Actuator which takes account of mechanical motion in multiple degrees of freedom (DOF). The circuit is derived by a purely theoretical procedure; A lagrange function of the Comb-Drive Actuator is first set up, and following linearization of the Lagrange's equation, results in a linear motion matrix. The obtained linear matrix is then divided into a mechanical matrix, an electrical matrix, and an interacting matrix which is composed of non-diagonal elements and denotes electro-mechanical energy conversion. The mechanical matrix and the electrical matrix are expressed by simple Combination of LCR elements, while the interacting matrix is configured by capacitances and dependent source elements. From the equivalent circuit, we can understand interaction, not only between the electrical system and the multi mechanical systems, but also between the different mechanical freedom systems. The equivalent circuit model in the 2DOF system is verified by comparing the experimental result of electrical admittance with simulation, using the developed equivalent circuit, and shows good agreement merely by fitting parasitic capacitance and mechanical resistances. A multi-DOF equivalent circuit is essential when simulating MEMS devices, such as gyro sensors in which at least two-dimensional mechanical motions must be taken in account.

N.f. De Rooij - One of the best experts on this subject based on the ideXlab platform.

  • Three-dimensional SOI-MEMS constructed by buckled bridges and vertical Comb Drive Actuator
    IEEE Journal of Selected Topics in Quantum Electronics, 2004
    Co-Authors: M. Sasaki, D. Briand, W. Noell, N.f. De Rooij, Kazuhiro Hane
    Abstract:

    A new method for realizing three-dimensional structures based on the standard silicon-on-insulator microelectromechanical systems is developed using vertically buckled bridges as structural elements. The vertical displacement, profile of the bridge, and obtainable accuracy of the displacement are examined. Using the lateral dimension control of the bridge and the supporting beams, the vertical positioning is realized based on the planer photolithography. As a demonstration, a vertical Comb Drive Actuator is prepared and its performance is examined.

  • miniaturized time scanning fourier transform spectrometer based on silicon technology
    Optics Letters, 1999
    Co-Authors: O. Manzardo, Hans Peter Herzig, C Marxer, N.f. De Rooij
    Abstract:

    We present a miniaturized Fourier transform spectrometer (FTS) based on optical microelectromechanical system technology. The FTS is a Michelson interferometer with one scanning mirror. A new type of electrostatic Comb Drive Actuator moves the mirror. We have measured a nonlinearity of the driving system of ±0.5 µm for a displacement of 38.5 µm. A method is presented to correct the spectrum to get rid of the nonlinearity. The driving reproducibility is ±25 nm. The measured resolution of the spectrometer after the phase correction is 6 nm at a wavelength of 633 nm.

Tatsuhiko Sugiyama - One of the best experts on this subject based on the ideXlab platform.

  • $In Situ$ Measurement of Charging Process in Electret-Based Comb-Drive Actuator and High-Voltage Charging
    Journal of Microelectromechanical Systems, 2015
    Co-Authors: Yasushi Shibata, Tatsuhiko Sugiyama, Hidenori Mimura, Gen Hashiguchi
    Abstract:

    We report in situ measurements of the charging process for an electret-based Comb-Drive Actuator and an experiment on high-voltage charging. The ac current flowing between the Comb-Drive electrodes, which is proportional to the displacement, is monitored during the application of a dc bias voltage at an elevated temperature. As the charge voltage increases, it opposes the applied voltage, causing the current to decrease and become a minimum, which indicates the completion of the charging process. The proposed electret-based method allows voltage-controlled charging in silicon microelectromechanical systems (MEMSs) devices, which offers advantages for commercial MEMS device fabrication. This paper also discusses the importance of high-voltage charging for improving the efficiency of the Actuator as an electrostatic vibration-energy harvesting device. A charging mechanism is proposed to explain the experimental results, and the stability of the movable Comb-Drive electrode against the pull-in effect is discussed. Using the proposed method, a large force factor is obtained, and charging to a voltage of up to 380 V is demonstrated.

  • Electrostatic micro transformer using potassium ion electret forming on a Comb-Drive Actuator
    2013 Transducers & Eurosensors XXVII: The 17th International Conference on Solid-State Sensors Actuators and Microsystems (TRANSDUCERS & EUROSENSORS X, 2013
    Co-Authors: H. Hayashi, Masato Suzuki, Tatsuhiko Sugiyama, A. Mori, G. Hashiguchi
    Abstract:

    This study reports the theory and the testing of an electrostatic transformer. We confirmed that 2 sets of electrostatic Actuators with thermal silicon dioxide electret, induced by highly doped potassium ions, can work as the AC voltage step-up transformer. The transformer ratio can be set arbitrarily by the ratio of the electro-mechanical conversion factor and the vibration amplitude of the electrostatic Actuators. And the electrostatic transformer works without any influence on the magnetic field and is lightweight. We made the experimental samples to verify our theory. And we try to improve this device to work as parts of a DC-DC converter.

  • SiO2 electret induced by potassium ions on a Comb-Drive Actuator
    2012 IEEE 25th International Conference on Micro Electro Mechanical Systems (MEMS), 2012
    Co-Authors: Tatsuhiko Sugiyama, Hiroyuki Fujita, Mitsuru Aoyama, Yasushi Shibata, Masato Suzuki, Takashi Konno, Manabu Ataka, Gen Hashiguchi
    Abstract:

    This paper reports a novel SiO2 electret on Comb-Drive Actuator, which is formed by concise procedure and low cost. The SiO2 electret is generated by doping potassium ions and formed on vertical walls of driving electrodes in a Comb-Drive Actuator. The current generated by the extraneous vibration was observed, so this device is thought to be useful as the vibration power generator.

  • sio2 electret generated by potassium ions on a Comb Drive Actuator
    Applied Physics Express, 2011
    Co-Authors: Tatsuhiko Sugiyama, Hiroyuki Fujita, Mitsuru Aoyama, Yasushi Shibata, Masato Suzuki, Takashi Konno, Manabu Ataka, Gen Hashiguchi
    Abstract:

    Silicon dioxide electret generated by doping potassium ions will be demonstrated by forming it on a Comb-Drive Actuator. The Comb-Drive Actuator made of silicon on an insulator substrate is oxidized with bubbling a stream of KOH solution to form silicon oxide film including potassium ions uniformly on the etched side walls of Comb electrodes. After a bias-temperature procedure at about 900–1000 K and 100 V was applied to the device, we confirmed a 40 V built-in potential difference between the opposing Comb electrodes. The gradual decay of the potential was observed, but 35 V was maintained even after 1 month.

Chengkuo Lee - One of the best experts on this subject based on the ideXlab platform.

  • Monolithic-integrated 8CH MEMS variable optical attenuators
    Sensors and Actuators A: Physical, 2005
    Co-Authors: Chengkuo Lee
    Abstract:

    Monolithic-integrated variable optical attenuator (VOA) array devices with eight channels are realized and characterized in this study. This VOA array device is derived by DRIE micromachining process and is controlled by using electrostatic Comb Drive Actuator. Both bright and dark types of VOA operations are presented with respect to in-line and reflection types of light attenuation configuration. This multi-channeled VOA device is potentially to be scaled up to 16 channels. Except to the state-of-the-art performance, the reported packaged devices have compact footprint of 18 mm × 18 mm × 5 mm. © 2005 Elsevier B.V. All rights reserved.