New technique using spray coating of photoresist is developed for realizing the photolithography on samples having deep three dimensional structures. This technique is compatible with the highly developed planar photolithography and therefore promising for realizing the wide variety of micro-electro mechanical systems. The photoresist is sprayed as minute particles and carried to the sample surface. The particle dries individually without suffering the problem due to the resist flow or the surface tension (e.g., disconnection of film or accumulation of resist at corners). The appropriate drying condition realizes the thin and uniform resist film. The effects of some parameters which have the significant influence to the spray coating condition are examined. The thin and uniform photoresist film is reproducibly obtained on the deep three dimensional structure. The patterning is demonstrated using the conventional exposing equipment not only at the planar area but also corners or slant surfaces.

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High Intensity pulse laser is very important device as a light source of LIBS. For obtaining high peak power and short pulses, different approaches based on MOPA (Master Oscillator-Power Amplifier) scheme of master oscillator (MO) power amplifiers(PA) can be used. We use Stimulated Brillouin Scattering (SBS) cell in the power amplifier for laser pulse compression. Compression of pulses by SBS allows potentially receiving pulses by duration down to 100 picosecond and has following advantages. The compression of pulses at SBS have enough large power efficiency (usually more than 50%), that is much higher than power efficiency of extracting of a short pulse, from a long “train” of mode-locked pulses or cutting of short pulse from a long Q-switched pulse. As a results, pulse duration of the laser which we have developed is less than 300ps at 50mJ out-put energy. This means that intensity of the laser is 20 times higher than conventional Nd:YAG pulse lasers.

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A fork-type micro connector with high aspect ratio and high packaging density was fabricated using UV thick photoresist and Ni electroforming. A negative photoresist (THB-130N) was used as a mold for Ni electroforming. The tips of the plug terminal of the micro connector were formed as movable portions using Cu sacrificial layer etching. In order to make firm contact of the micro connector, a two-step guidance was adopted. The size of the terminal of the fabricated micro connector was 50 μm-thickness and 15 μm-width (minimum). The maximum aspect ratio of the fabricated micro connector was 3.3 and the terminal pitch 80 μm. A contact resistance of 50 mΩ, a contact force of 2.08 mN, Young’s modulus of 80 GPa and a permissible current were obtained for practical use for the micro connector.

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A prototype self-standing polysilicon-metal junction thermopile has been developed. In order to realize ideal higher thermal isolation, a thermopile without a membrane and having self-standing structure is proposed. It is arbitrary to select the heat absorber or the substrate as a hot contact, i.e. the hot and cold contacts can be inverted. The thermocouple is composed of an n-type polysilicon and an Au junction. The thermopile was fabricated by MICS (Multi-user Integrated Chip Service: three polysilicon layer structure) organized by the Cooperative Research Committee for Standardization of Micromachines in IEE of Japan. Output characteristics were measured as a function of distance between the hot contact of the thermopile and the radiation source, in order to confirm performance of the proposed thermopile as an accessory micro power generator. Seebeck voltage of more than 6.2mV was obtained in the case of connecting ten thermocouples is series for typical human skin (307K) used as a radiation source.

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This paper describes a new method for distinguishing objects on and alongside the road using a scanning laser radar (SLR) and a vehicle-mounted camera. Objects are detected on the basis of SLR digital signal data and the types of objects are distinguished by using their movement vectors and positions relative to white lane markers. For object detection, a new two-step grouping method is proposed for improving detection accuracy. The movement vectors of objects are adjusted properly based on the steering angle and speed of the host vehicle. The proposed method has been validated on a simulator using data recorded at a velocity of more than 40km per hour on Japanese expressways. The expected discrimination of vehicles, delineators and overhead signs in the forward view was successfully achieved in the simulation.

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One of the problems to realize safe and reliable social system is to reduce the cost and time for maintenance works. In the presently available maintenance style of large-scale facilities with big and complex structure like power plant, suspension of operation and concomitant jobs like disassembly and reassembly of the object facilities are necessary. Especially in maintenance requiring access to parts assembled in narrow places like pipes inside the facility, these jobs are unavoidable. But from the viewpoint of operating efficiency, the style of maintenance and inspection without need of such disassembly and reassembly jobs is much desired. In this sense, the micromachine which can easily go into the narrow places, is expected as one of the new methods to realize unmanned maintenance. To use micromachines as intelligent actuators for operations in narrow places, it is desirable to endow micromachines with functions to move individually and to work cooperatively in a group, because the micromachine miniaturized enough to go into the narrow place is restricted in its functions, and it is difficult to realize high speed and high output jobs by a single unit. The objective of our research is to develop a control system for multi-micromachines to construct desired work patterns. In this paper, we propose an algorithm to generate desired patterns and show some experimental results.

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We have developed an infrared detector and a micro variable infrared filter for micro-spectrum analyzing devices. Two infrared detectors and the infrared filter were mounted on the identical package. A micro-spectrum analyzing device of 1cm³ volume as the two wavelength NDIR system for combining these elements with the infrared source was able to measure the concentration of carbon dioxide.

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Semiconductor magnetodiode with very small size, which has similar operation-principle to the SMD (Sony magnetodiode), has been fabricated on a thin Si film of SOI substrate and its fundamental characteristics are evaluated. This magnetodiode is able to fabricate together with ICs such as amplifier, driving circuits, compensation circuits, etc. using the update semiconductor IC technologies on a Si chip. Double injection in this magnetodiode is confirmed, and the magnetic sensitivity of ΔI/I₀∼=10% at H=1kOe is obtained in this double injection regime even under non-optimized conditions.

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