An ultraminiature sensor for thermal analysis is fabricated using micromachining technique and its fundamental characteristics are obtained. This device consists of monolithically integrated components of an air-bridge type microheater, a thin film thermocouple and a sample-holder. Boiling points of liquid samples, water and methanol, are clearly observed in the heating curve and the heating-rate curve, and sudden decrease of the temperature at the dropping time of the liquid sample without heating due to the effect of evaporation heat is also observed.

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CdTe semiconductor radiation detectors, including CdZnTe detectors, have disadvantages in that they are very difficult to use to measure the γ-ray energy in the high energy region above 1 MeV because of the small mobility of charge carriers, although they can be used at room temperature. It was suggested that a stacked structure of CdTe elements be used in order to improve the sensitivity in the high energy regions. In this paper, it is suggested that a highly precise detector response simulation within 5% errors of the full energy peak efficiency be conducted to provide ideas for the design of the detector structure. The fundamental characteristics of both the CdTe detector and CdZnTe detector were investigated to evaluate the feasibility of the high energy region sensitive Cd_1-xZn_xTe detector.

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This paper describes a new ultrasound intravascular imaging system. In this system, an ultrasound probe consists of a micromotor, an ultrasound reflecting mirror attached with the micromotor and an ultrasound transducer. Ultrasound is scanned radially by a micromotor instead of a rotation transmitting wire and the rotation of the micromotor is performed and controlled by an external magnetic field. This ultrasound imaging system with a micromotor was applied to observe the inside of blood vessels through in vitro experiments. The preliminary results suggest that this system has the sufficient ability to define the blood vessel morphology and that the simple image processing enhances signal-to-noise ratio of the reconstructed image.

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An odor sensing system based on a SAW device has been developed for the measurement of odors from herb, which is a common name of the grass effusing relatively strong odors, and recognition of eight kinds of herb odors was performed using the system. Four kinds of lipid films were used as odor sensitive film in the study. The lipids of the films are (1) lecithin from eggs, (2) sphingomyelin, (3) L-α-phosphatidyl ethanolamine solution 70%+phosphonicacid dioleyl ester 30% and (4) cholesterol 70%+sphingomyelin 30%. The lipids were applied to the SAW resonator surface by spin coating, at speed 3000 r. p. m. for 20 seconds, from a lipid solution of 20μl. A neural network algorithm was applied to identify the odors. In the recognition process, patterns consisting of maximum frequency changes of the sensors and differential frequency changes of the sensors between adsorption and desorption of the odors were taken as inputs of the network, and the patterns were normalized by a specific normalization method, so that the recognition of the odors was improved and done at rate of 99%.

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A scratch drive actuator (SDA), which consisted of a bushing and a plate, was one example of an electrostatic microactuator. We analysed an elastic deformation of the SDA. The analytic method of an elastic deformation caused by the electrostatic force is described. The elastic energy and the electrostatic energy were used to calculate the elastic defromation of the SDA. The obtained results were used to explain a theoretical microstep of the SDA. The method we described is applied to analyse the elastic deformation of the electrostatic microactuators.

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A silicon resonant angular rate sensor (gyroscope) with ring - disk - shaped resonator was fabricated using silicon bulk micromachining and its properties were investigated. The sensor consists of a glass-silicon-glass structure. The ring - disk - shaped silicon resonator has 3300μm×3100μm size and 30μm-thick. The resonator is suspended by four beams, and the ends of beams are anchored to a support which is in the center of the ring. The silicon structure was machined by alkali etching and reactive ion etching. Driving the resonator and detecting the vibration are performed by electrostatic forces and capacitive changes between the silicon resonator and electrodes on the glass. The resonant frequencies of the test device were 4.2kHz in driving mode and 3.5kHz in detecting mode. Although the difference in resonant frequencies between two modes was about 20%, a noise-equivalent rate of 3deg./sec was obtained at 7 Pa.

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