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In this paper, we report the structure and the fabrication process of the new Micro-Electro-Mechanical Systems (MEMS) Fabry-Perot Tunable Filter (FPTF) device with Ag alloy mirror which is tunable in the wide wavelength range of visible light. The device has very simple structure, which consists of two substrates that are bonded by using novel bonding technology, polymer films, and inert gas plasma treatments. We confirmed that the wavelength of the 1st order transmission peak of fabricated device can be adjusted to a 400-700nm range by applying the different DC voltage. Our MEMS FPTF device successfully operates in the wide wavelength range of visible light, shows good agreement with simulation result.

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We have investigated 3D profiling of the objects by low coherence optical interferometer using MEMS grating. This system, constructed with optical fibers and MEMS devices, is Fourier domain interferometer, which can discriminate distance to the object by wavelength analysis of the interference spectra. A MEMS mirror gives the object 2D optical scanning, and a MEMS grating makes spectroscopy of interference spectra. The MEMS grating can tilt to dual-axis with electromagnetic force induced by planer coils and a permanent magnet. One axis tilting works as near infrared spectroscopy, and another axis tilting works as optical axis alignment in an interferometer. Fabricated MEMS grating could tilt ±3.5° (mech.) / less than ±10mA in both direction at low frequency, which were equivalent to approximately 1400-1700nm in wavelength. This interferometer, whose S/N was 50dB and vertical standard deviation was 0.6µm, could scan full wavelength width (1400-1700nm) in 25ms. Finally, we could realize 3D profiling which was not only surface reflection profiling of 1µm step, but also transparent profiling of IC process layer from backside of the wafer.

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In the emerging fields related to healthcare, energy, and environment, realization of devices on large area flexible sheets is imminent. Weaving e-textile with fibrous devices comprising warp and weft is one of the methods to realize such devices. Especially with a display or with a 2-D matrix sensor, a distortion of image, or error in positional information can occur if these matrices get misaligned. Therefore securing of the matrix becomes necessary. However, in a traditional textile, due to weak binding force in shear direction at the intersection of warp and weft, the displacement of intersection often does take place. So we propose to make a weaving guide in a form of dent structure on the fiber substrate. To realize this strategy, we developed a system to produce such weaving guides onto a fiber with improved productivity. To maintain a constant press force onto the fiber substrate during imprint, and to stabilize deformation volume, we adopted a press force control mechanism. As a result we obtained a stable and uniform deformation of imprinted weaving guides. Finally, to validate the weaving guide, we made two samples using 3×3 fibers, with and without the weaving guides. We saw distinct difference between the two samples.

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This paper describes the design and fabrication of a microlens for the sensitivity improvement of uncooled infrared array sensors. We improved the sensitivity by collecting infrared rays to detectors. The microlens is made of silicon, which is a typical substrate for MEMS technology. We fabricated it by photolithography technology using a gray scale mask and an etch-back process by selectivity-controlled dry etching. This process enables us to fabricate a 43-µm-high silicon microlens from only a 2- to 3-µm-high photoresist structure. To confirm the usefulness of the microlens, we developed a small infrared array sensor with microlens. The results show that the sensitivity improvement with the microlens is 4.2 times. Microlens is one promising technology for sensitivity improvement.

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