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In machining of the products in which a large number of cutting tools and machining processes are needed, the factors related to productivity such as machining time, machining cost and power consumption vary by sequence of machining. In this report, to develop the supporting system for process planning including above factors in machining with machining center, Dijkstra′s algorithm is used. The machining time on the basis of NC data is calculated and the minimum machining time in machining for a product needed 15 processes (the number of tools is 10) is analyzed. From the comparison of machining time obtained for various sequence of machining, it is confirmed that the analytical result is valid.

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In this research, for retaining the machining information such as machining features and machining strategies, the ISO 6983 NC data are analyzed based on a next-generation CNC control language (ISO 14649) which contains the machining information explicitly. In previous report, the method for grouping tool paths from ISO 6983 NC data based on geometric information of the tool path was proposed. In this report, the grouping method for a multistage machining using type of group and motion direction of tool paths is proposed, and the software to display extracted machining information with an expertise is developed. The machining information is integrated, retained on the machining database, and displayed by the software.

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In a manufacturing system, the digital tools such as CAD and CAM are used and communication among them frequently occurs. However, interoperability among heterogeneous software systems and tools is generally not available. To solve this problem, a digital machining information (DMI) model to support a real-virtual machining system is proposed in this study. In this report, a machining environmental resource model which is a part of the DMI model is developed. The machining environmental resource model consists of a model of the ancillary equipment for machining tool such as automatic tool changer (ATC). Using this model, the total motion time and the total used energy can be calculated. While changing tool, the collision can be also detected.

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New carbon materials such as Fullerene, nanotube and nanocoil were discovered recently. There is a possibility for being other unknown carbon materials. In this paper, modeling of new carbon materials and their stability of structures are analysed by molecular dynamics simulation. As a result, it is shown that ring-structure, tetra-structure, cubic-structure, and diamond-structure of nm-level have stable crystal structures.

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Theoretical analysis and finite element simulation have been carried out for a constant specific load rate indentation creep test. Analytical results indicate that both the representative stress and the indentation strain rate become constant after a transient period. Moreover, the finite element simulation reveals that both the contours of equivalent stress and equivalent plastic strain rate underneath self-similar indenter evolve with geometrical self-similarity. This suggests that pseudo-steady indentation creep occurs in the region beneath the indenter. The stress exponent for creep can be obtained exactly from the pseudo-steady indentation creep data. These results demonstrate that the constant specific load rate testing technique can be used to evaluate creep parameters with the same accuracy as conventional uniaxial creep tests.

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Centerless Grinder is composed of Grinding Wheel and Regulating Wheel and Work blade and is used to grinds the cylindrical workpiece. Throughfeed grindig means that one process from rough grinding to finish and spark-out grinding is done while workpiece passes from the entrance to exits.The feed power and feed on workpiece are adjusted by the Regulating Wheel incline.Also the grinding allowance configuration is greatly affected by the Regulating Wheel incline at the same time and about 20 factors on grinding conditions.The experts have adjusted this allowance configuration by their experience and feelings.And in this report the relationships between the setting workpiece condition and the grinding allowance are analyzed on the expert experience and simulated.

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Multi-tasking machine tools are powerful to manufacture complicated workpiece with high productivity. However, NC data generation for Multi-tasking machine tools is very difficult when using such machine tools. There are some CAM systems for Multi-tasking machine tools, however they have such problems as the manual allocation of parts to generate tool paths, the difficulty of self-interference recognition without simulator and so on. Therefore, the study deals with the development of the system which can recognize part configurations, calculate tool paths automatically for turning and milling operations, sort them in machining order and generate NC data, based on 3-D CAD data of workpieces.

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The purpose of this research is to develop hi-speed and hi-accuracy machining system. The servo data is the set of position command at every servo cycle time, which is minimum unit of position command in NC machining processes. The servo data is directly generated by geometric model interpolation without NC program. In this research the tool path generation system that is able to predict and compensate the tool deflection and fluctuation of cutting load is proposed. This report refers to the algorithm to calculate the removal volume in consideration of a tool deflection.

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The purpose of this research is to develop hi-speed and hi-accuracy machining system which is corresponded to 1 micron of accuracy. The servo data is the set of position command at every servo cycle time, which is minimum unit of position command in NC machining processes. The servo data is directly generated by geometric model interpolation without NC program. And motion errors are simulated and compensated automatically. This report refers to the result of machining test to verify the developed prototype system.

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Indicative of the rapid technological progress in automotive sensors, automobile has advanced very much and changed to environmentally friendly cars that are capable of obtaining higher gas mileage and are safer and more comfortable. The same thing can be described from view points of the number of sensors used in vehicle. A current luxury car contains approximately 100 sensors although cars in the early 50′s didn′t have any sensors. This paper contains how the automotive systems and sensors are used in cars, how the system control automotive functions, and how the sensors are made. In this paper, future roles of MEMS technologies in automotive electronics are also discussed.

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To reduce the thermal stress in the fine-pitch flip-chip interconnections due to the thermal expansion mismatch of the different materials, a low-temperature bonding process, surface activated bonding (SAB), is therefore expected especially in high-density packaging. In principle, the SAB method needs a high vacuum environment to prevent the activated surfaces from being oxidized. Due to this basic concept, little work has been conducted to examine the bonding feasibility of micro-bumps in ambient air using low-pressure Ar RF plasma activation. In this study, the effect of low-pressure Ar plasma treatment on fine-pitch micro-bump bonding is investigated. The function of Ar plasma treatment was evaluated by bonding micro-bumps of Au-to-Au, Au/Sn-to-Au, and SnAgCu-to-SnAgCu at 25-200°C. The activation surfaces of Au, Sn and SnAg films were analyzed by X-ray photoelectron spectroscopy (XPS). Carbon contaminants are removed from the surfaces, whereas oxides were detected in the case of Sn and SnAg due to the residual air in the low-pressure condition. Low-pressure Ar plasma treatment improves the bondability of Au and Sn-Ag-Cu micro-bumps at low temperatures in ambient air. 100% bond yield was achieved and the die shear strength was higher than 20 MPa.

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Wafer bonding has been considered as is developing as a promising technology for manufacturing MEMS and 3D integration. Precise alignment is necessary to achieve well-aligned wafer bonding enabling accurate interconnections to be made between layers. In this paper, a novel centrosymmetric square moire pattern is developed for aligning between the top and bottom wafers. Simulation results show the mismatched moire fringes produced by the two centrosymmetric square patterns are highly sensitive with the misalignments and misaligned directions without requiring any external reference. We fabricated these centrosymmetric square patterns, which occupies the minimum area on the wafers. Using two pairs of these moire square patterns, misalignments of the bonded wafers are determined in X-Y-θdirection simultaneously over the entire area of the wafer. In our experiment, the misalignments in the order of +/-0.5 um in X-Y direction, as an example, can be easily identified using a simple IR microscope. Moreover, compared to Si topographical moire patterns, the metal centrosymmetric moire patterns show a better optical contract that does not depend on the gap between the top and bottom wafers. It is feasible for wafer-to-wafer alignment because this gap is changing from tens of micrometers to zero during the alignment process. Meanwhile, the alignment inaccuracy using this moire pattern will be also estimated in this paper.

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We succeeded in the complete transcript of line / space pattern with the 1-um line width and 1-um depth on polyethylene terephthalate (PET) by using ultrasonic nanoimprinting. Molding conditions such as contact force, contact time, frequency, amplitude of ultrasonic vibration, and buffer materials were optimized for PET imprinting. Polymethylmethacrylate (PMMA), polycarbonate (PC) and other engineering plastics were imprinted under the same conditions. As a result, it was proved that the imprinted depth was changed according to the glass transition temperature of each engineering plastic.

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In the fields of optical- and chemical devices, there is an increasing demand for low-priced, high-throughput and flexible ultra-precision fabrication technologies for glasses. As a low-cost glass forming process with high manufacturing output, our research group has put the focus on glass embossing with the glassy carbon (GC) mold machined by focused ion beam (FIB). Additionally, we also attempted other structuring methods such as mechanical dicing and laser beam machining techniques for fabricating GC mold to overcome demerits [e.g., slow processing time and small working area (less than several hundred micrometer square)] of FIB milling technique. However, machining resolution of both dicing and laser beam machining are much lower than FIB milling. In this work, we fabricated GC molds by dry etching with electron beam (EB) lithography and applied them to glass and metal embossing.

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In this study, a novel fabrication method for fabricating a microcoil structure was developed by utilizing polydimethylsiloxane (PDMS) as a three-dimensional (3D) mold material. The developed fabrication method was consisted of pre and post-processes. As a first step of pre-process, a master pattern with a spiral structure of microcoil shape was accurately transferred to a mold cavity shape by pouring and hardening PDMS surrounding a mater pattern. Within the cavity of the fabricated 3D PDMS mold, an ultraviolet (UV) curable resin structure was precisely replicated along the surface of a cylindrical Al wire deposited with Au-Ti. This replicated UV curable resin replica was utilized as the base component for the fabrication of a microcoil structure by electroplating. Finally, a microcoil structure was fabricated by a post-process containing electroplating, dry and wet etching. An outer diameter, line width and coil thickness of the fabricated a microcoil structure were 538, 12.3 and 8.2 µm, respectively.

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