We have developed a new micromachined nano tweezers integrated with thermal expansion micro actuators.The device structure was de.ned by etching of a 30µm-thick silicon-on-insulator wafer (SOI) using an inductively coupled plasma reactive ion etching apparatus (ICP-RIE). To obtain the tip radius of less than 10nm and to align two probe tips, new process sequence was designed by combining wet anisotropical etching of silicon with the ICP-RIE. The gap between the two probe tips can be controlled by the integrated Si thermal expansion acutuators which are 500µm in length, 50µm in width, and 30µm in thickness. Since the displacement of the probe tip is mechanically magni.ed by 5 times as the thermal expansion displacement, 2µm displacement toward the opposing probe tip was observed when 0.4 W was applied to the thermal expansion actuator, which quantitatively agreed with theoretical prediction.

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Passive Tire Monitoring System (PTMS) enables to detect pressure, temperature and ID number of each tire. And it also can warn drivers about low pressure or flat tires. In our proposal, the sensors to detect tire pressure are implanted in each tire. Therefore, they must have a robust structure enough to withstand against an overload pressure that is applied during curing process of tires, as well as a high sensitivity and its good linearity in their operating range. Touch Mode Capacitive Pressure Sensor(1) seems to be suitable for this system, because it has some advantages such as near linear output, strong endurance against overload pressure and a robust structure compared with other conventional pressure sensors. The purpose of this study is to improve the minimum burst pressure of the Touch Mode Capacitive Pressure Sensors in the high volume production. As a result of observation with AFM and TEM, we found that some etch-pits, which are produced in etching process of the diaphragm of the sensors, make the diaphragm weak. Consequently, we could optimize the etching conditions, and obtain the sensors of which the minimum burst pressure is 3.5MPa and more at a high yield rate.

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Receiving tactile information from a slave-robot is a necessary component of telexistence with haptic display, but there are few tactile sensors that can measure the distribution of three-dimensional force vectors on a surface. For this reason, we developed a sensor that provides three-dimensional force distribution by detecting movement vectors in the transparent elastic body with a video camera. From a result of the experiment, it turned out this approach is effective.

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In this paper, a novel microfluidic device for mixing liquids is described. Main feature of this device is that the liquids are passively pumped through microchannels only by capillary action, and therefore no external power is required for the pumping. This feature brings extremely simple hardware setup and easy operation. In this device, a pneumatically-actuated, normally-closed microvalve regulates capillary-driven flow. The device has been fabricated with polydimethylsiloxane (PDMS) elastomer, and tested using fluorescent dye and fluorescent particle solutions. A simple method for controlling the mixing ratio is also demonstrated.

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