A dual quartz sensor has been developed which enables the analyses of physicochemical properties of liquids. In this sensor, an ACR (Antiparallel Coupled Resonator) type quartz sensor and a LFE (Lateral Field Excited) type quartz sensor were fabricated on a same plate. The ACR can measure frequency response caused by a mechanical characteristic (viscoelasticity) of liquids. The LFE can measure frequency response caused by both the mechanical characteristic and the electrical characteristics (conductivity and dielectric constant) of liquids. By subtracting the frequency shift of the LFE and the ACR, the dual quartz sensor is possible to calculate the electrical characteristics. Therefore the dual quartz sensor allowed simultaneous measurements of electrical characteristics and the mechanical characteristic of a liquid.

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Test devices for evaluating the stress effect on Hall element have been designed and fabricated using a simple SOI-MEMS process, where a Hall element is incorporated onto a micromachined cantilever together with floating electrodes connecting the input/output terminals of the Hall element. The predetermined stress was applied by pushing down the tip of the cantilever using a stimulus attached to the XYZ manipulator. The test devices of <110> and <100> directions were measured, whose magnetic sensitivities were increased by 6.5% and 12%, respectively, by applying the stress of 218 MPa. These experimental results agreed reasonably with the calculated values using a simple model.

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The FePd/PZT/FePd and the FePd/PZT stacked-layer magnetic sensors were studied. A magnetic field was applied to the longitudinal direction of the sensor to cause a longitudinal stress magnetostrictively, which produces a piezoelectric output voltage in the PZT layer. The prototype sensors are 15 mm long and 6 mm wide and the thicknesses of the FePd layer and PZT layer are 10 µm and 330 µm, respectively. The theoretical sensitivities of the FePd/PZT/FePd sensor and the FePd/PZT sensor using a simple cantilever model were calculated to be 0.29 mV/A/m and 0.15 mV/A/m, respectively. The measured sensitivities agreed reasonably with the calculated ones.

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An electrostatic micro actuator with an electrical contact between the electrodes is known to show a limit-cycle behavior due to the combination of electrostatic pull-in and release. We newly used an electrical circuit simulator to make an equivalent circuit model to reproduce the limit-cycle by multi-physics simulation. This simulation results were found to explain the experimenntally observed behavior of the developedMEMS voltage to frequency convertor (VFC).

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The prototype of the pneumatic micro dispenser chip for portable micro analysis devices was developed successfully. This micro dispenser succeeded to divide liquid into 1µL without any dead volume by decompressing and the compressing air in only one micro pump. The dispensing operation is achieved by the original micro liquid detecting method and four hat-shaped check valves. The detecting method utilized the refraction of the infrared rays LED. Not only passage of the fluid into the channel but also its existence can be detected as TTL level signal. The hat-shaped silicone rubber valve which functions itself as a unidirectional passive valve was proposed. The check valve with low opening pressure (3kPa) and high inverse pressure (over 300kPa) was developed successfully. This micro dispenser chip is useful for portable micro analysis devices.

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We propose a sensor that provides position measurement for a particle in a micro channel fabricated with polydimethylsiloxane (PDMS) chip. By irradiating a plastic optical fiber (POF) array arranged across the micro channel with a light source, the particle position is measured by the change in POF output power. The effects of the optical axis misalignment between POF, the particle size and transmission were calculated to evaluate the measurement principle. We fabricated a sensor integrated with a PDMS micro channel made by soft lithography. The sensor was examined experimentally by measuring the output voltage from a photodiode and calculating the decrease in POF output power in the presence of a particle. The measurement result of our fabricated senor was compared with the particle image recorded with a CCD camera attached to a microscope. The experimental results indicate that our proposed sensor can be adapted for use in automated cell manipulation.

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We propose a CMOS-compatible and mechanically reliable MEMS fabrication process for integrated micromirror. In this paper, design and evaluations of the micromirror fabricated by the proposed process is described. Residual stress deformation of electrodes and buckling of torsion beams were suppressed by rib structures and appropriate layout of support anchors. Highly stable characteristics of the micromirror were demonstrated by evaluation at temperatures from 30 to 150°C.

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In recent years, the increase in traffic accidents associated with drunk driving has become a serious social issue. Therefore, there is a need for an in-vehicle system that can detect the fact that the driver is under the influence of alcohol. We thought a method for alcohol detection in the breath of the driver, based on a nondispersive infrared (NDIR) method, is suitable for this system. Since alcohol content in the driver's breath is significantly diluted at the sensor device, it is necessary that the sensor is highly sensitive to detect diluted alcohol. A quantum cascade laser was used to produce highly intense infrared light source. An infrared hollow fiber used in medical treatment was utilized as a gas absorption cell. Since the core of the fiber is hollow, gas is introduced for analyzer. The flexibility of the fiber allowed it to be looped so that 2 m fiber in length could be formed into a compact coil of 29 cm in diameter. It was clarified that the light intensity change of light output from the hollow fiber with ethanol density, and rarefied ethanol as small as 1 ppm in density was detected.

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In this paper, we propose and demonstrate, for the first time, a testing method without applying the stress on the etched surface roughness of sidewalls to evaluate intrinsic material's reliability. The specimen is a square membrane constituting from polycrystalline silicon, silicon dioxide and silicon nitride, which has a cylindrical Si-weight at the center and is supported by Si-frame. The load to the membrane is applied by vibrating the specimen in out-of-plane direction near the resonant frequency. The initial fracture strength of 250 nm and 500 nm thick poly-Si film has been revealed as; 2.59 GPa and 2.28 GPa in average, 0.17 GPa (6.6 %) and 0.28 GPa (12.1 %) in standard deviation, 15.2 and 9.94 in Weibull modulus, respectively. The Weibull modulus was much higher than previous researches since smaller surface roughness increases the fracture strength and decreases the deviation. As a next step, fatigue lifetime will be also examined using the same setup with long-term constant cyclic loadings.

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