Resonant Micro Research Articles

Characterization system for resonant micro- and nanocantilevers

We present a system for characterization of the resonant properties of micro- and nanocantilever sensors. The system has been constructed as a vacuum chamber with capabilities for controlling environmental conditions such as pressure, temperature, and chemical constituents. Characterization can be achieved either electrically or using a specialized laser-optical detection system. The system has been used to characterize the resonant properties of SiO2 cantilevers as well as other resonant structures. We present experimental results of a SiO2 resonant cantilever, showing an exceptional accuracy in resonant frequency determination, and demonstrating the importance of resonance characterization in a controlled environment.

Evaluation of Human Bone Elastic Stiffness by Resonant Ultrasound Spectroscopy and Micro Finite Element Method

Evaluation of Human Bone Elastic Stiffness by Resonant Ultrasound Spectroscopy and Micro Finite Element Method

Absolute potential of the Fermi level of isolated single-walled carbon nanotubes

Electrochemical potential dependence of Raman intensity of isolated single-walled carbon nanotubes (SWNT) on gold electrode in aqueous solution was investigated employing in situ resonant confocal micro Raman spectroscopy. Absolute potential of the Fermi level of individual tubes was estimated from the potential dependence. Observations suggest that the work function of the tube becomes larger in a manner inversely proportional to the diameter of SWNT. The structural dependence of a metallic tube is larger than that of a semiconducting tube.

On the Temperature Profile of the Thermally Excited Resonant Silicon Micro Structural Pressure Sensor

AbstractAccording to the sensing structure of a practical silicon resonant pressure micro sensor whose preliminary sensing unit is a square silicon diaphragm and the final sensing unit is a silicon beam resonator, its operating mechanism is analyzed. The thermal resistor acts as the excited unit, and the piezoresistive unit acts as the detector, for the above micro sensor. By using the amplitude and phase conditions, the self-exciting closed loop system is investigated based on the operating mechanism for the above micro sensor. The temperature profile model and the thermal stress model are established for the beam resonator of the micro sensor. Moreover, the thermal feature is simulated and analyzed for the above micro sensor.

Detailed analysis of the intracavity phenomena inside a cylindrical microresonator

Based on a rigorous analysis of the intensity distribution inside a cylindrical microresonator (MR), a detailed description of the wavelength and spatial dependence of the intracavity intensity is given. The theory is in accordance with photon scanning tunneling microscopy (PSTM) of an integrated optics MR. Good agreement between the theory and the PSTM measurements is found.

Cavity element for resonant micro optical gyroscope

Significant strides have been made towards a feasible resonant micro optic gyro (RMOG). Uniquely crucial components have been developed. Experimental measurements, when coupled with theoretical analysis predicts that 1 degree/hour performance can be achieved. Three critical elements required for the successful development have been demonstrated. A high quality trench waveguide has been designed, fabricated and demonstrated to have losses as little as 0.1 dB/cm. The waveguide has been demonstrated to have gain in the 4.0 dB/cm range. Finally, a waveguide laser has been fabricated and has shown nearly enough power to adequately drive an RMOG. Analysis of the measured performance predicts that a 1 degree/hour RMOG can be constructed. The small size and projected ruggedness of the RMOG will be advantageous in high G applications. Other applications, such as man portable guidance systems, where weight and size are critical, may also benefit from RMOG technology.

Impact, Friction, and Wear Testing of Microsamples of Polycrystalline Silicon

ABSTRACTThis paper gives an overview of the recent developments in impact, friction, and wear testing of polycrystalline silicon (polysilicon) based micro electromechanical structures. Impact-friction actuated micromechanisms form a new type of actuators. In this type of actuators, lateral resonant structures are retracted by electrostatic comb drives and are propelled forward toward the actuated micromechanism by elastic forces generated by folded beam flexures at frequencies ranging from 10 kHz to 20 kHz. This sequence generates normal impact and tangential friction contact between the two microstructures, raising wear concerns. Two sorts of impact test structures are introduced in this paper, One with a resonant micro impact bumper (MIB) striking a stationary impact wall anchored ofn the substrate. Another is a testing of two MIBs driven to impact each other. Two types of impact actuators are also described, an impact actuated micro angular oscillator (MAO) and a polysilicon micro vibromotor. The vibromotor is a rotor driven by oblique impact on the rim by a converter pointer tip attached to a lateral resonator. Some initial results of impact wear testing as well as static and dynamic friction done by researchers in the field are also described in the paper. Finally, many areas where material scientists can contribute to this field are suggested.