A wafer of the microdevices is usually cut into the chips by the dicing process after 3D-microstructures and circuit patterns are built on both faces of it by Si-micromachining process. However, unlike LSI’s, the microdevices have some factors, such as the deep pattern on both faces, which make the dicing process hard and sometimes cause the defective ones. Taking the case of a micro-probe, one kind of microdevice, applied for testing LSI’s, we clarified the problems in the dicing process, such as incomplete electric isolation of each probe, stain and big chippings, peeling of circuit layer, and tight tolerance in dimensions. We studied out the new dicing method to solve these problems by optimizing the thickness of the circuits and the dicing blades, applying a cutting to both faces, making a non-adhesive areas in the dicing tape facing the circuit pattern areas on the wafer, forming a cutting area on the wafer. We think these studies can apply the other microdevices.

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This paper reports key issues of packaging for sensor and actuator MEMS (Micro Electro Mechanical Systems) devices. In this paper, we focus on the two types of MEMS devices, the sensor MEMS and the actuator MEMS. In the case of sensor MEMS packaging, the thermal stress is the most important in order to prevent the deterioration of its sensitivity. On the other hand, in the case of actuator MEMS packaging, it is important to design the packaging for enhancing the device characteristics.

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The present paper describes a sensor for measuring the glucose concentration of yeast culture medium. The sensor determines glucose concentration by measuring the yield of hydrogen peroxide produced by glucose oxidase, which is monitored as luminescence using photomultiplier. The present sensor is able to measure low glucose concentration in media in which yeast cells keep respiration state. We herein describe the system and the characteristics of the glucose sensor.

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A new technique has been introduced to deposit amorphous hydrogenated carbon films (a-C:H) by pulsed laser deposition (PLD). Camphor, a natural source, has played a crucial role for the evolution of the film from amorphous carbon (a-C) to amorphous hydrogenated carbon (a-C:H). This has been confirmed by the presence of C-H stretching bond observed in the FTIR absorption spectra. The influence of camphor incorporation to the optical, electrical, and structural properties of the carbon film has been investigated by UV-visible spectroscopy, FTIR spectroscopy, Hall measurement, and Raman shift. As a kind of photo detectors, a solar cell with a-C:H/p-Si structure has been fabricated, its current-voltage (I-V) characteristics and spectral response are also studied. From the measurement of quantum efficiency, we find that the light sensing property of the new type of a-C:H film have been improved notably. In the short-wavelength region, the a-C:H layer contributes a maximum quantum efficiency as high as 30% despite the light loss by the surface electrode.

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