This paper reports a new fabrication process for nano composite structure by combination of nano plastic forming, coating and polishing techniques. By this process, nano line arrays, nano lattice arrays and nano dot arrays of various metals were fabricated on the surface of soda glass plate experimentally, and feasibility of this process was validated. Transparency of the fabricated nano dot array was analyzed. Results indicates possibility to control optical functions by means of fabrication of nano composite structure.

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This study aims to clarify the influence of surface topography on the photocatalytic function of TiO_2 film surface to support the manufacturing high-performance photocatalytic films. In this report, a few textured TiO_2 film surfaces were produced by conducting the anodic oxidation to the titanium plates with micro cutting grooves under various cutting conditions, and the wettabilty which is one of the photocatalytic functions was evaluated. As a result, it is understood that the wettability of manufactured TiO_2 film is improved with increasing the real surface area, and it is also confirmed that the high-performance TiO_2 films can be manufactured by combination of the microcutting and anodic oxidation, even though further increase in the real surface area is necessary.

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This paper discusses the design of microstructure on a handle or handrail of welfare equipments to prevent slip accidents. Friction between a rubber block and a rigid body were measured on a original set-up. The rubber and the rigid body simulate human finger and handel respectively, and deterministic microstructures were fabricated on both surfaces using photolithography process. The effect of typical parameters were made clear including the effect of environments, dry or water between the surfaces. It was found that proper microstructure keeps the factional foce almost constant independent of conditions. It was also found, based on sensory tests, that structural pitch 300mm can minimize the pains while keeping frictional force properly.

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The machine tools are required speed-up and working with high accuracy. To achieve the two factors, our study have done improving the performance of sliding characteristics of slideway which has high stiffness, high damping capacity and easiness of installation of the machine tools used in processing system. The feature of our experimental apparatus is able to examine with a large-scale(100cm^2) test piece in large measuring range. We give the texture of the dimple shape on the sliding surface and examine lubrication properties. The texture was processed by the sandblast method. In this report, the eddy current displacement sensor was installed in the experimental apparatus and we experimented under oiling condition. As a result, we were able to measure the oil film thickness and we have understood that the oil film thickness depends on oiling rate.

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Silicon based ceramics easily give low friction coefficient of the order of 0.001 under water lubrication condition. Such low friction with water is a promising technology for environmental demands of no pollution and saving resources and energy. The low friction of silicon based ceramics in water is considered to be achieved by hydrodynamic lubrication, which is attributed to a smooth surface formed by tribo-chemical wear and a tribo-reaction product. In this study multi-scale surface texture to control smoothness of the surface, formation of the reaction products and their achievment speed are proposed. As a result, it is clearly shown that the multi-scale surface texture can provide lower friction, higher loading capacity and wider operating condition with low friction of silicon based ceramics in water.

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Nano-structure-based patterning of nanometer thick lubricant films is presented. Nanometer thick lubricant films can be patterned on the nanometer-scale using the oxide nano-structure fabricated by probe oxidation. We clarified that the lubricant distribution strongly depends on the shape of nano-structure.

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This paper describes the fabrication methods nano-scale patterns composed of two kinds of materials. Fabrication methods are as follows: first, microscale pattern of the periodic slope array is fabricated on a substrate; second, multilayer films are deposited by physical vapor deposition (PVD) process; finally, the substrate is polished and the film materials appear on the surface as parallel stripes. The microscale pattern was fabricated on single crystal silicon substrate using photolithography and anisotropically etching techniques, The combinations of Fe-Au, platinum and aluminum (Pt-Al), alumina and aluminum (A1_2O_3-Al), and Si carbide and carbon (SiC-C) were deposited. The target thickness of each layer was 50 nm to 300 nm. During the polishing or by an additional etching, one material became higher than the other material. Thus, nanoscale ridge array could be formed.

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We fabricated the combination of micro- and nano-sized surface texturing by a novel nano-patterning method that is robust against wear or plastic deformation. The combination of Fe and Au successfully formed the nanometer-size patterns based on the multilayer structure because the size and direction of the patterns coincided with the anticipated results from the multilayer structure. The frictional properties of Fe-Au were examined using our pin-on-plate tribometer. The results indicated that nanometer-size texture formed on the flat surface we fabricated is considered to have a great effect on the tribological properties of these materials, especially in boundary-lubricated regime.

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This paper describes the concept of fabricating nano-patterned surface on irregular structure. Many researches on friction reduction using micro textured surface has been reported. Almost of them made patterned texture using laser beam machining or etching etc, and clarified that the dimple or groove patterned surface affect on friction reduction. On the other hand, our group is developing the nano scale patterning composed of two kinds of materials on micro patterned surface. This paper proposes to fabricate random texture without micro patterning. The combinations of Fe-Au were deposited on shot blasted surface by physical vapor deposition (PVD). The friction tests were carried out using ball-on-block type machine, and difference of the friction coefficient by the existence of the abrasion was confirmed.

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Patterning and coating of sliding surface are important tribotecuniques to contribute to resource saving and energy conservation. We evaluated friction and wear characteristics of nano-pattern on cast iron substrate fabricated by the combination of shot-blast treatment and physical vapor deposition (PVD) of Au and Fe using a ball-on-plate reciprocating tribotester (SRV tribotester). As a result, the surface with nano-patterning showed lower friction coefficients than the surface with only shot-blast treatment and the untreated surface under dry and lubricated conditions. The Au layer was thought to function as solid lubricant especially in case of dry condition. Additionally, there was a possibility that an effect of oil sump induced by the multilayer structure decreased friction coefficients in case of lubricated condition.

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We propose and demonstrate Bonding-in-Liquid Technique (BiLT) for encapsulation of liquid in MEMS devices. Liquid encapsulation enables innovative MEMS devices with various functions. Interfusion of air bubbles, heterogeneity of the liquid quantity, and leakage of the encapsulated liquid must be averted not to deteriorate device performances. In BiLT, two structural layers are passively aligned and brought into contact in solution, where the encapsulation cavities are uniformly filled up with the liquid without air bubbles. A UV-curable resin is used as an adhesive that does not require heat or vacuum environment but UV to bond the two layers. We successfully achieved encapsulation of DI water and glycerin in silicon structural layers. Since conventional aligners are not applicable to BiLT, we experimentally evaluated the accuracy of the passive alignment process in solution that makes use of matching concave and convex structures.

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We developed a MEMS-based hydraulic displacement amplification mechanism (HDAM) with completely encapsulated liquid for tactile displays applications. The fabricated mechanism creates amplification through a micro-chamber with different cross-sectional areas etched in a silicon wafer. The chamber is filled with glycerin, an incompressible fluid, and sealed by two thin largely deformable membranes of polydimethylsiloxane (PDMS) by using ultraviolet curable resin as an intermediate layer. By combining HDAM with micro-actuators, we can amplify the input displacement generated by the actuators through the HDAM and use the output displacement to stimulate tactile receptors. To optimize the characteristics of the HDAM, FEM analysis has been performed and we obtained a device able to amplify displacement of piezoelectric actuators up to 15-fold.

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This paper proposes master slave system with feedback haptic for micro manipulator using micromachine technology. This system consists of a slave device for micro manipulator and a master equipment for PHANToM with haptic feedback. The employed device is based on the principles of the PBA(Pneumatic Balloon Actuator). It is possible to design a small, soft and safe surgical tool by using PBA, which is made of PDMS(polydimethylsiloxane) and driven by pneumatic pressure. For example, we operate the retractor holds the abdominal organ to the side during the entire operation to keep the sight and operational space, dissects the mucosa under observing the submucosa in endoscopic surgery and outer shell actuator manipulate a forceps by controlling individual deformation of surrounding balloon. We report control method of operation and haptic feedback of these manipulators and cxaluation result.

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This paper describes a capacitance type airflow sensor, based on insects' sensillar seta. Some insects such as crickets begin escape behavior by sensing a minute airflow with sensillar seta. The sensor consists of a metal cantilever and an insulation layer. Air flow bends a hair connected to the cantilever, which causes the deflection of the cantilever and change in the capacitance between the cantilever and the substrate. The sensor was attached to the linear guide and moved at various speeds up to 750mm/s. The capacitance was measured using an LCR meter. The results showed that the capacitance increases linearly with increasing speed of air flow ranging from 350mm/s to 750mm/s.

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Detection of the line-of-sight (LOS) has various applications, such as communication technology and welfare field. To realize such applications, there is strong demand for an LOS detection system that does not restrict users' activities and inflicts no mental stress. In this paper, we propose a novel wearable pupil position detection system, featuring minimum disturbance to users, both physically and mentally, via the use of dye-sensitized photovoltaic devices. These devices are transparent and generate voltage according to the incident light intensity. Arraying the devices on eyeglasses, this system detects the difference in the reflection light from the pupil and the white of the eye and hence determines the position of the pupil.

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Demands for sub-meso scale devices from millimeters to sub-millimeter in size are rapidly growing. However, currently we have no effective methods of manufacturing these devices. We aim at development of ultra fine single-crystal diamond tools that are high precision, mass producible and low costs. In this paper, we propose the processing principle of a single-crystal diamond using photolithography process and thermochemical reaction with sidero-metal based on the processing experiments with various conditions and surface element analysis. We have elucidated that our processing is initiated by the diffusion of carbon into the metal and then promoted by the owidation of diamond. The etching rate of diamond increases with the annealing temperature, and we ascertain that annealing temperature should be less than 1150K to prevent combustion of diamond. Additionally, we found that the etching rate depended on the crystal orientation.

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Metal NPs have been studied for ultrasensitive chemical/biological detection exploiting the local surface plasmon resonance [1] and as a catalytic material because of their extremely large surface/volume ratio [2]. When different metal NPs are hetero-structured, different excitation wavelength can be used to detect various chemical/biological species ultra-sensitively. When applied as catalysts, multiple chemical reactions can be catalyzed. To make a practical use of these promising applications, development of formation processes of hetero nanostructures capable of controlling composition and patterns is mandatory. In this paper we demonstrate formation of hetero nanostructures consisting of silver and gold NPs. A surface of a glass substrate is chemically patterned with micro-contact-printed self-assembled monolayer (SAM) with amino terminal groups, hi the following chemical reduction processes of gold and silver NPs in the liquid- phase, gold NPs are preferentially deposited on the SAM-patterned areas and silver NPs are formed on bare glass surfaces. We have successfully achieved patterning of silver and gold NPs. Heterogeneity of nanostructures was verified by UV-Visible spectroscopy

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We propose a polymer-metal hybrid MMT (magnetically driven microtool) which has properties of both elasticity and rigidity. A magnetic metal axle is made by electroplating, then it is mounted directly in the center of the MMT during molding. By using this process, we could fabricate a hybrid MMT whose fixed axes are elastic to move specific direction, while the center axle is rigid to prevent bending by the unwanted external force. The magnetic metal axle also has a merit to have higher magnetic property which contributes to the powerful actuation. We designed a hybrid MMT for on-demand droplet dispensing on a chip. It has a parallel plate structure to be constrained in translational motion. The displacement of the hybrid MMT was about 300 μm which was 6 times larger than that of the conventional MMT, and on-demand droplet generation was successfully performed. We confirmed production of the 177.7± 2.3 μm droplet.

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We succeeded in size-dependent continuous particle filtration and particle trap using magnetically driven microtool (MMT) and centrifugal force in a microfluidic chip. Novelties of this paper are summarized as follows. (1) Filtering efficiency was improved than filtration by solely centrifugal force by MMT rotation. (2) This filtration is robust against pressure fluctuation in a chip by mechanical particle separation using sidewalls. (3) Size-classified microparticles can be trapped in the microchannels and treated by reagent. Microparticles having different sizes flow in circular microchannels and separated according to their sizes by the graduated gaps between sidewall and bottom by centrifugal force. MMT is positioned inside the microchamber and rotated by external magnetic force. Rotation of MMT enhances the sorting efficiency. By flow control, size-classified microparticles can also be aligned in the circular microchannel and retrieved concurrently. We demonstrated filtration of the microparticles using 3D-MMT rotation and centrifugal force and trap of the size-classified microparticles in a chip.

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We report the method for control technique of nanoparticles. We demonstrate the use of alternating current inhomogeneous electric field generated by electrodes, for the control of nanoparticles. The electrodes are made of ITO on glass was fabricated by micro-electromechanical systems (MEMS) technology. In recent years, a study of handling aimed at analyzing living body nanoparticles such as DNA or the protein is performed flourishingly. In this study, we use the dielectrophoresis (DEP) that is one of the handling techniques. The dielectric migration used the interaction of an induced particle and the electric field in the inhomogeneous electric field. Unlike the electrophoresis, we are able to control a particle without the electric charge cells and microbes of the quantity of slight electric charge by low voltage. However, Brownian motion becomes dominant if particle diameter becomes small. So, we handle the nanoparticle by restraining the Brownian movement of the nanoparticle.

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Hepatocytes are responsible for metabolic and detoxification processes in the liver. During the tissue formation from isolated cells, they increase the cell density and acquire their liver-specific functions, new protein expression and cell signaling. Hence, tissue-based in vitro studies are strongly demanded. Spheroids are promising research target for this purpose that are aggregates of cells and retain three dimensional structures and tissue-specific functions. Recently several methods of forming spheroids were reported. However, they are not capable of controlling the geometry of spheroids. We propose a three dimensional spheroids of hepatocytes formation platform using micro-swirling flow. The flow can control the spheroid formation speed and the three dimensional geometry. Such three dimensional spheroids formation platform will not offer only new experimental systems that imitate tissues for biological research but also efficient drug screening systems and hybrid artificial organs with high cell density and hepatic functions.

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Measurement of force with precise control between machine elements is needed for clarifying tribological properties of micro- and nano-machines, whose sliding gaps are very small. In this talk, we report simultaneous measurements of lateral and vertical forces by using double-ended tuning fork (DETF) resonator and optical fiber sliding probe.

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Atomic force microscopy (AFM) is recognized as indispensable for micro-electromechanical systems (MEMS), nanotechnology, and nano-biotechnology. Although observing bio-related samples in a liquid environment using AFM is increasingly important, deformable, uneven, and easily damaged surfaces of biological specimens require establishment of non-contact AFM observation. Contact mode and dynamic mode are AFM's two measurement methods. The latter reproduces the surface shape from variation appearing in the vibrating micro-cantilever's resonance, depending on change in the atomic force acting between the probe and the sample surface during measurement. Because soft irregular bumpy surfaces of biogenic samples are easily damaged, contact-mode AFM is unsuitable for samples of biological origin. Instead, non-contact observation using dynamic-mode AFM must be established. Toward observation of nanometer-scale biological samples in a liquid, this paper reports frequency-modulation atomic force microscopy (FM-AFM). It can avoid both collisions by the probe-cantilever with the sample surface and stops of oscillation by vibrating the probe-cantilever similarly to van der Pol-type self-excited oscillation.

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Piezoelectric MEMS deformable mirrors have been developed for high resolution retina imaging using adaptive optics. For the low voltage drive, piezoelectric PZT thin films-were used to actuate the mirror surface. In this study, we fabricated hexagonal 61-element actuator array to enhance the performance of image correction. In order to reduce the dead space for the lead lines between the actuators, the polyimide insulating layer was coated on the surface of the PZT actuators and lead lines were prepared with the connection to each element. The displacement of each actuator was measured by using a lasor Doppler vibrometer and we confirmed a relatively large displacement of more than 1μm by applying a voltage of lOVpp. Furthermore, we measured the relationship input voltage and displacement and fabricated DMs actuated linearly when applied -20〜20Vpp.

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This paper presents fabrication and characterization of narrow gapped silicon dual nano probe for atomic force microscope. Each probe has a silicon nano tip on a cantilever, on which a thermal actuator is formed to depart the probe from sample surface when the other probe is used for AFM imaging. By supplying electric power of 9mW (30mA) to the thermal actuator, each cantilever can be heated up to 40℃, resulting in deflection of 2.5μm. The non-heated probe was also deflected approximately 0.5μm during the other probe heating. However, AFM image was successfully obtained by the non-heated probe with high stability.

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Recently, crystal growth in the microgravity is attracting attention because it has possibility to produce uniform crystal. The purpose of the study is to manipulate a particle with micrometer of diameter and to produce crystal coincidentally. Cylindrical electrodes were prepared for Paul trapping effect and electrospray ionization was brought in to charge particles. A micro particle of solid, liquid and solution have simple harmonic motion behavior. A theoretical model of a trapped particle based on Mathieu function is proposed and its behavior is suited for simple harmonic motion. As a result, charge amount of a trapped particle is dependent on its size and material.

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Recently, the frequency fluctuation of MEMS oscillator is a problem. We consider that the influences of the thermal noise and the existence of the interface state cause the frequency fluctuations. Two types of charge fluctuations, interface state trap noise from Shockley-Read-Hall model generation and thermal noise generation, are able to simulate as the frequency fluctuation in MEMS oscillator, respectively. In this paper, based on a simple model of a parallel plate MEMS oscillator, two types of the frequency fluctuations theory and their width are demonstrated.

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We propose a novel concept that self-organized vasculature integrates artificial orifices on a microfluidic device using inducible protein VEGF (Vascular Endothelial Growth Factor) for fluid induction into vasculature. Micro gel beads containing VEGF immobilized on orifices, it is able to induce angiogenesis to orifices on embedded channels. Endothelial cells (HUVEC) characteristically organize vasculature by themselves in collagen gel and grow along the VEGF concentration gradient. HUVEC were cultured on the device for a day in collagen gel and vasculature was forming on orifices by self-organized. And angiogenetic effect was evaluated quantitatively.

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This paper describes a fabrication of SPR(Surface Plasmon Resonance) chip with micro structures by an imprint technology. We developed the SPR chip with the filter effect by the micro structures on which were fabricated the SPR chip whose height are more than the sensing area in SPR sensing. We examined the fabrication of processes the SPR chip with the filter effect by using the imprint technology to fabricate the chip with low cost. We evaluated the characteristics of the chip, then confirmed the feasibility of the lows cost filter chip.

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We developed a micro-fabricated chip to separate bio-molecules by their molecular sizes based on the principle of the size exclusion chromatography (SEC). The nano-sized fence array was integrated in our chip for the separation. One of the features of the chip is that the separation property can be controlled by the design offences' size and their arrangement. In this study, we constructed the theoretical model to estimate the separation properties of our chip assuming the motions of the DNA molecules as random walking spheres. Validity of the model was confirmed by comparing the results of theoretical calculation and those of the experiments.

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We investigate multi-layered thermal nanoimprint to fabricate 3D-structure. In multi-layered imprinting, the relation between imprint condition and fabricated structure has not been discussed experimentally. In this report, we discuss simple bi-layer imprint experimentally. Bi-layer PMMA resist coated two type molecular weight polymers is pressed in some conditions and observed cross-sectional images. As a result, imprinted structure is affected pressure force and pattern width.

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Carbon Nanotubes (CNTs) are anticipated that they are utilized as nano/micro structures for bio-analysis. Vertically aligned CNTs (VACNTs) were synthesized on Si/SiO_2 substrate by Chemical Vapor Deposition. CNTs on Si/SiO_2 were transferred onto microchannel made of PDMS by using its adherence. The characteristics of CNTs were evaluated when CNTs was contacted liquid such as DI water, ethanol. Furthermore CNTs clumped together and micropatterned themselves when liquid which penetrated among CNTs dried. Finally, CNTs and micropatterned CNTs were applied as structure to increase reaction area for substrate reaction. The results shows the CNTs have potential as functional structures for bio-analysis.

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The deforming of thin metal films on PET substrates is studied. Though only polymer substrates are deformed in conventional nanoimprint lithography studies, we pressed metal-polymer composite specimens which may be applied to micro electromagnetic or optical devices. 100 nm Al thin films were deposited on 50 μm PET substrates for specimens. The thin metal films on PET are pressed for loading time t=300, 900, 1800 s with a mold patterned lines. As a result, thin metal films are strained 1.7 % at most.

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