We report that an ultra-small laser scanning module of millimeter size was realized. This laser scanning module consists of silicon substrate, a laser diode array with multi-emitter, and microprisms. The microprism measures 180μm wide, 100μm high, and 80μm thick. The smaller the optical elements used, the more precise the alignment accuracy required. The microprisms and alignment pins for laser diode array are fabricated on the same silicon substrate using MEMS technology. Then the laser diode array is attached to the silicon substrate by setting with the alignment pins. The alignment accuracy was ±2.8μm for the interval between the laser diode array and microprisms. The rotational angle accuracy of each axis was within ±0.3 degrees. This high alignment accuracy has been achieved without camera.

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This paper reports integration of quartz-crystal microbalance (QCM) sensors on a monolithic quartz crystal plate without using microfabrication. The QCM sensor used for this study is specially developed for sensing within a microfluidic channel. In this study, the distance between QCMs was optimized by monitoring frequency change caused by a mass load onto a neighboring QCM. It was found that circular shape QCM is suitable for the integration. The optimized QCM array was used for monitoring an etching of a gold electrode of the QCM by electrochemically generated oxidant. The measured phenomenon is practically useful for the cleaning of an integrated sensor within a packaged microfluidic channel.

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We have extended measurable pressure range of the thin film Pirani vacuum sensor that is still sensitive above 1×10⁵ Pa (1 atmosphere). In our thin film Pirani vacuum sensor, our proposed temperature difference sensor of the short circuit Seebeck-current detection type thermocouple is used in order to get extremely high sensitivity, especially both in very low pressure range and in higher pressure range than 1×10⁴ Pa. In our new pressure sensor the cantilever type sensing region, in which a microheater and two thermocouples are formed to measure the temperature difference, is adopted. Therefore, we can use the null method to measure very small pressure accurately in the high vacuum range (low pressure range). On the other hand in the higher pressure than 1×10⁴ Pa., we could expand the pressure range by adoption of the vibration of the sensing cantilever based on the sudden heating due to the exchange of heater driving. We have achieved much wider measurable pressure range over 8 digits by use of our new simple thin film Pirani vacuum sensor than that of the traditional one.

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This paper proposes a novel tactile sensor system, which acquires sensing data by interrupt data transmission from each tactile sensor element. The interrupt makes decentralized sensing data transmission. Compared with existing centralized tactile sensor systems, the system can handle a large amount of tactile sensor elements and attach the elements on the arbitrary surface of the robot, because decentralized serial bus communication and the integration of a MEMS sensor and a signal processing LSI realize low power consumption, high speed response and flexible network morphology. In this paper, we focus on system analysis and LSI design for the system. Experimental results show that response time and power consumption of a tactile sensor element, which is composed of a MEMS capacitive force sensor and a signal processing LSI, are 21μs and 2mW, respectively. The computational experiments proved that more than thousands of the elements can be mounted in the system.

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The Si-MCP with a high aspect ratio produced by the wet or dry etching technique of Si for micro channel formation and the CVD method for secondary electron multiplying film growth have been developed. The micro channel formed on the (110) Si substrate by anisotropic wet etching is a slit structure. On the other hand, the micro channe1 formed by using Deep-RIE is not only a pipe structure but also inclines. The CVD lead glass and the poly-Si film have been introduced as a secondary electron multiplying film. The gain of 54 was obtained at a dynode voltage of 600 V by the slit type Si-MCP with CVD lead glass, which had the maximum secondary electron emission coefficient of 1.9 at 190 eV.

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In this study, electrolyte-based level sensor has been fabricated on printed circuit board and evaluated with charge balanced C-V converter fabricated by 0.35μm CMOS process. Sector pattern sensor electrodes were fabricated and polydimethylsiloxane was used as package material. Propylene carbonate was injected in the bumpy surface sensor cavity of 10mm diameter and 2mm height, output voltage was changed with the inclination angle without the effect of vibration.

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This letter presents the fabrication process of a hybrid MEMS device, which integrates PZT (PbZrTiO₃) actuators into a silicon microstructure. A microassembly technique which employs vertical well structures to allow precise positioning of MEMS devices onto a substrate, is demonstrated in this paper. The silicon microstructure is fabricated by deep reactive ion etching, and metal patterns are formed on it by photolithography using a thick photoresist. Ceramic PZT actuators are also fabricated using micro fabrication processes. The stacked PZT actuators are inserted into photoresist frame, and mechanically and electrically connected to the silicon structure using Ni electroplating. Using this method, the fabrication of micro XY-stage with Si-PZT hybrid structures is demonstrated. This technique is applicable to any number or combination of MEMS devices which require precise positioning onto a substrate, under micron-scale tolerances.

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In this study, photo-darlingtons have been developed by using standard CMOS process for visible light communication. The practical application of the photo-transistors is focus for visible light ID which uses the carrier frequency of 28.8kHz. The response sensitivities of photo-darlington was 9times higher than that of typical PIN photo-diode, and the response frequency was 110kHz.

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We have developed the light sensor of searching and tracking the sun in the sky to raise the efficiency for electric generation of solar cell. The sensor proposed in the present paper is composed of a declined photodiode. The azimuth and elevation of light source are estimated by rotating the photodiode. The principle is expressed, and the result of basic experiment is shown.

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In this paper, the fabrication method of high aspect ratio tapered structure is proposed by using chemically-amplified epoxy-based negative resist SU8. Proximity exposure technique is used from the backside of 150μm thick glass substrate to change the amount of exposure by using conventional mask. The amount of exposure was transformed into micro tapered resist structure. Slit pattern from 5μm to 35μm width was designed and exposed, the difference of exposure amount causes the resist height change from 25μm to 180μm. Polydimethylsiloxiane (PDMS) surface was transformed from the resist structure in order to improve the water-repellency. The repellency was highest at the diameter of 20μm, and the maximum contact angle was 172°and 165°on the average.

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