The development of micro gas preconcentrators is crucial for the realization of miniaturized gas chromatography (micro-GC) systems which are expected to open up new applications such as breath analysis. One of the major problems with the reduction in the preconcentrator size by miniaturization is the availability of a sorbent material having high enough concentration factor. Single-walled carbon nanotubes (SWNTs) are one of the promising materials for high adsorption capacity. In this report, a gas preconcentrator having a depth of 40 μm and a volume of 1 μL was microfabricated. The synthesized SWNT films with a thickness of 30 μm were embedded in the micro gas preconcentrators by using the hot water-assisted detachment method. The small size of the fabricated micro gas preconcentrator and the use of SWNTs as the adsorbent material allow for achieving a concentration factor as high as 16000 for 2 ppm octane. This concentration factor value is the highest reported to date for micro gas preconcentrators and sufficient for micro-GC detectors to concentrate trace analytes of interest for breath analysis. It is concluded that micro gas preconcentrators using SWNTs as the adsorbent material have great potential to concentrate compounds.

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We developed vacuum-packaging equipment and low-cost vacuum packaging technology for IRFPAs. The equipment is versatile and can process packages with various materials and structures. Getters are activated before vacuum packaging, and we can solder caps/ceramic-packages and caps/windows in a high-vacuum condition using this equipment. We also developed a micro-vacuum gauge to measure pressure in vacuum packages. The micro-vacuum gauge uses the principle of thermal conduction of gases. We use a multi-ceramic package that consists of six packages fabricated on a ceramic sheet, and confirm that the pressure in the processed packages is sufficiently low for high-performance IRFPA.

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Structural properties of Si films deposited at 300°C, using plasma enhanced chemical transport method, were investigated. Obtained deposition rate was 6.5nm/min and calculated residual stress was about 300Mpa (compressive). X-ray diffraction (XRD) pattern and Raman spectra indicate that the films on both on Si and glass substrates are composed mostly of poly-Si. And the crystallite size on glass is smaller than that of the Si substrate.

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Tactile array sensors with three inclined micro-cantilevers embedded in elastomer, which can detect both normal and shear forces, have been designed and fabricated. The inclined cantilevers consist of multilayer of Polymer/NiCr/SiN/Si and the normal and shear forces are detected as resistance change of NiCr thin film induced by deformation of the cantilever. This tactile sensor has sensitivity linear to normal and shear forces. Moreover, this sensor can detect normal and shear force by the resistance changes of 3 cantilevers.

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A wireless smart-scales system with a face recognition function has been developed as an application for wireless sensor networks. The face recognition employs a wireless camera; and the system automatically identifies a person and stores the weights of all the people that use the system on a server. Two key ultralow-energy circuit techniques were devised for the smart scales. One is a nearly-zero-standby-current circuit that combines a mechanical switch and an electrical CPU-controlled power switch; it reduces the standby power dissipation of the CPU from 1.5 mW to less than 0.1 μW. The other is a super-intermittently-operating circuit with a power-switch transistor and a small resistance; it suppresses the energy dissipation of the wireless camera to just 1/4 of the total energy dissipation. Furthermore, an electromechanical micropower generator with electromagnetic induction further reduces the energy dissipation. It is located under the scales and supplies a power of 75 mW during one second.

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This paper describes UV adhesive bonding of lithium niobate (LN) and silicon (Si), and the following polishing of LN, which are key technologies in wafer-level integration processes for LN acoustic devices on LSI. Five UV adhesive candidates were investigated in terms of bonding-induced stress and removability by O₂ plasma treatment. The latter is important because the UV polymer is used as a sacrificial layer in the above processes. Based on the results, we selected one usable UV adhesive, and obtained bending-free LN/Si hybrid substrates, overcoming a large difference in the coefficient of thermal expansion between LN (7.5 (c-axis) - 14.4 (a-axis) × 10^-6 /K) and Si (2.6 × 10^-6 /K). The LN substrate on the Si substrate was thinned and surface-polished by an experimentally obtained recipe. Finally, a mirror-finished LN layer with a thickness of ca. 10 μm was successfully obtained without noticeable cracks. It was confirmed that this thin LN layer survived in the fabrication process of surface acoustic wave (SAW) devices.

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This study presents the design, fabrication and characterization of an ultra miniaturized 3-axis accelerometer based on micro/nanoelectromechanical systems (MEMS/NEMS). This accelerometer designed and fabricated as small as with overall dimensions 700μmX700μmX550μm length width and thickness, respectively. It can detect three components of acceleration simultaneously.. The sensitivity could be enhanced significantly while miniaturizing the die size of sensor chip with the aid of novel structure and nano-scale piezoresistors on the sensing beams. Therefore, this novel proposed sensor is showing good performance and smaller than other comparable miniaturized sensor structures reported thus far. The accelerometer is capable of measuring accelerations up to ±50g in the frequency bandwidth of 300Hz accordance with finite element simulation.

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The piezoelectric RF-MEMS tunable capacitor having the divided piezoelectric actuator to realize multi-step operation was studied. The results of structural analysis indicated that the divided actuator enabled to differ gap between movable electrodes and fixed electrode in capacitor area originated in curling over width direction. The fabricated tunable capacitor showed 6-step operation and maximum capacitance 0.70 pF at 600 MHz with actuation voltage 5.2 V. As a result, the tunable capacitor having the divided actuator was successfully fabricated to provide multi-step operation.

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An excellent cavity ring-down spectroanalyzer was realized using a reflective semiconductor optical amplifier. A negative feedback optical amplification effect of the amplifier recovers signal loss to a higher definition and provides an output signal whose baseline was reduced optically.

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