Applications of diamond abrasives wheels have been spreading in the field of planarization of Si wafers. Under such circumstances, this study aims to clarify the removal mechanism of Si wafer surface by a diamond abrasive in an atomic level. This paper reports on the results obtained through the nano–scratching simulations by using the molecular dynamics method and the experiments in atmosphere by an atomic force microscope (AFM), respectively. From the simulation results, the formation of amorphous phase around the scratched groove was observed. On the contrary, according to the experimental results, the formation of the embossment on the scratched area was observed.

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A new simulation method has been proposed in which an MD model is considered as an assemblage of atomic clusters and displacements of clusters are controlled so as to follow the analytical expression of the Mode II type displacement field around a crack tip. The results of the simulation show that there is a need to use acceleration–control for cluster motion because constant–speed–control of clusters causes false phenomena when a true state involves suddenly evolving phenomena.

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Renormalization Group Molecular Dynamics(RGMD) has been proposed in which viscosity caused by atomic motion in and between clusters is taken into account. The validity of the assumption used to derive viscosity effect is inspected and it is found that the assumption is not valid in some cases. Then, a new method to evaluate the viscosity effect has been proposed. A result of tensile fracture simulation of copper is in good agreement with actual phenomenoa.

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Dip–pen nanolithography(DPN) is a method to carry out patterning directly on a substrate by using a scanning probe microscope (SPM) having a probe with molecular ink.Although physical properties of substrate and molecular ink areimportant,the mechanism of patterning has not been clarified yet.Then ,to examine this mechanism,DPN is simulated by using Molecular Dynamics for various wettabilitybetween substrate and ink. It has been found that patterning can bemade when wettability between substrate and ink is stronger than wettability between a probe and ink.Increase of wettability between substrate and ink results in lower but wider pattern.

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For a feasibility study of plastic working at nanometer level with higher production efficiency and lower costs, molecular dynamics computer simulations of nano–drawing and nano–bending of monocrystalline copper wore carried out. .The results show that, in nano–drawing, stable drawing can be possible with the die the diameter of which is larger than 6.28nm. However, in case of nano–bending, the dislocations generated during loading process disappear from the specimen surface during unloading process. As a result, permanent deformation does not occur. To realize the nano–forming by plastic deformation, heat reatments before unloading are inevitable.

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[in Japanese]

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Making surface of insulation layer flat using CMP(Chemical Mechanical Polishing) is important for producing IC(Integrated Circuit).
Although simulations of CMP have been carried out using various methods to clarify working conditions, behavior of slurry including polished debris has not been clarified yet.
In this paper, simulation of CMP is carried out using SPH(Smoothed Particle Hydrodynamics) in which slurry including polished debris can be handled.
It has been found that a strong interaction between polished debris makes debris accumulate easily in ditches on a polishing pad and that the debris goes up again and harms the polished surface when the ditches are shallow.

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Creativity is the key for an innovation in product developments, however it has been regarded as a mysterious inner process of an individual. Recently, finding user need is thought to be a good strategic way to generate a creative solution. The topics of this research consist of a cognitive and sociological meaning of observation, designers′ thinking process in design fields, and an organized observation method for better sharing and idea creation in a group. Through a set of those researches, I aim to define a framework of an initial part of whole design process, in which design methodology has not been discussed well. This paper introduces a summery of the whole approaches featuring a result of an interview research with product designers in Japanese corporation and a result of an experimental research of a proposing observation method with mobile phone cameras.

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In 1st report to 4th report, We reported about a methodology of algebraic description and validation for user interface of embeded system. In this report we are going to present an integration of our method and ″BehaviourView″ plat form. This plat form is developed as a result of our project.

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FFD(Free–Form Deformation) is a popular method for deforming free form surface in the styling design stage. Traditional FFD first embeds the free form surface model in the parameter space defined by lattice. Then by deforming the lattice and embedded model is deformed. However in this method it is difficult to make handle suitable for user intend deformation type such as bend or twist, and requires complex lattice(handle) manipulation for deformation. Therefore we present a new deformation method using barycentric coordinate for Convex Polyhedra, and auto handle construction method driven by classification of deformation types.

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This report presents a new method to transform a generic face model for a facial expression change on a virtual space. Since the real expression change is made by the contraction of facial expression muscles, we make a model of the expression muscles and place the operating points of GFFD (Generalized Free–Form Deformation) on the model of the muscles. When some expression muscles contract, the corresponding operating points of GFFD move, and the facial model is transformed to represent a certain facial expression. In this case, we use the Gaussian function as the base function of GFFD. The Gaussian function has the standard deviation in each axis. By choosing the value of each standard deviation, we can control the range of the influence of the transformation. Thus, we can represent the feature of each expression muscle, and we can obtain the natural expression change. Some examples will finally be shown.

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The representation of muscle is one of the studies on representing a human body in a virtual space. In conventional studies, muscle has been represented by oval spheres, curved surfaces, and so on. In this study, we focus on the fact that muscle is composed of many fibers, which are called muscle fascicles. By modeling the muscle in the fascicle level, we can easily make various forms of muscles, and can transform the forms of any muscles systematically, such as expansion, contraction, bending, and so on. We made some muscle models of the upper arm and simulated the transformation of the muscles in bending and stretching exercises of the arm. As a result of this simulation, we are able to confirm that the visual effect is satisfactory.

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Shape deformation by using Finite Element Method outputs accurate results, but this method needs much calculation, and requires various ideas, for real–time processing.
Our method using tensegric model and t–FFD is effective to simulate a shape deformation of complicated models with an interactive speed.
This paper proposes a new method to constrain the deformation of the tensegric model, as if it is tightened by a wire–like object. When tensegric model is deformed, the wire–like constraint tries to keep its length, and affects the model with pseudo forces.
This method is expected to simulate the shape deformation of a human body constrained by a wearing corset.

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Computer–aided design (CAD) systems have been developed for modeling the desired 3D forms of products and they are proving useful for increasing efficiency of detail design. However, it is often difficult to use CAD systems for aesthetic design because style design is creative activity and strongly depend on creativity of designers.In the process of embodying the external form of a product, sketch is used as the most efficient tool. Sketches are classified into thumbnail sketches, idea sketches, rough sketches, and rendering sketches from the degree of embodied idea. In this paper, a system to support deciding a product–form in the rough sketching process is proposed, and the procedures to decide and modify the sketch lines are described.

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A method to generate a fair curve by specifying the curvature distributions. Control points are calculated based on the specified curvature distributions using least square method. Example of the generated curves are shown with curvature distributions. Curve segments are connected with curvature continuity.

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Recently, as CAD systems have been spread, style design with digital mockups has been used. But the method using physical mockups is still used to evaluate products from ergonomic design. However, the conventional methods of the evaluation using a physical mockup of a product are inefficient in an upstream style design process, for it costs time and money. So, our research purpose is to develop a system for ergonomics design, which enables an ergonomics evaluation for a palmtop IT device without ″real″ subjects and physical mockups by integrating a digital hand with a product model and its task operation model.

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The curve is the most basic design element to determine shapes and silhouettes of industrial products and works for shape designers and it is inevitable for them to make it aesthetic and attractive to improve the total quality of the shape design. If we can formulate the aesthetic curves, it is expected that the quality of the curve design improves drastically because we can use them as standards to generate, evaluate, and deform the curves.
In this paper,we discuss the properties of two typical aesthetically beautiful curves: the logarithmic spiral and the clothoid curve and we derive a general formula of aesthetic curves that describes the relationship between their radii of curvature and lengths inclusively expressing these two curves. Furthermore we show the self–affinity possessed by the curves satisfying the general formula of aesthetic curves.

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In the early stage of style design, in order to obtain aesthetic surfaces, designers have to repeat the following processes: generating shapes with free–form surfaces, evaluating their three–dimensional shapes, and refining them based on the results of evaluation. In these processes, it is desirable that designers can modify surfaces smoothly as they want. In the previous report, we have defined a surface as the trajectory of a ruler moving along two guide curves, and a generation method of fillets which satisfy G2 continuity at the boundaries. In this report, we propose a parametric design method that allows designers to create aesthetic shapes and surfaces by changing proposed parameters.

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In this paper, we propose impedimenta bypass method using key–frame method. Character bypasses impedimenta by pseudo force. When there is an impedimenta on character path, character′s nodes forced by impedimenta and pseudo force moves character′s nodes. A movement of one node affects all other nodes.

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While calculation of reaction force in object cutting, we have to subdivide the original mesh of finite element method in the field where the stress concentration can be observed.
It causes a huge computational complexity. We constructed object cutting simulation system that is able to output reaction force to force feedback device using OpenGL library. The system consists of high speed deformation calculation using rough mesh, and static and dynamic calculation method of calculates reaction force to cutting tool.

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A method of small patch division milling that can generate a geometric surface pattern by a ball–end milling to the machined surface is proposed. The whole machining surface is divided with small patches of the same size of triangle, quadrilateral or hexagon, then each small patch is processed by helical tool path with high feed rate. The geometric surface pattern with the cutting edges is generated within each patch and the whole machined surface is covered with the patches at the same time. These processes are demonstrated with the experiment and the developed simulation in this report.

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By applying the burnishing process, not only surface roughness but also residual stress state and micro hardness within the surface layer can be improved as usual. . In this study, a new type burnishing tool that rubs on the machined surface with high rotational speed is proposed, and the capability of the enhancement of the material/mechanical properties on the surface by the proposed tool is reported. The tip of the burnishing tool stirs within the thin surface layer under high strain rate in this process. After the friction stir burnishing on 0.45% carbon–steel with the carbide tip tool, very hard layer over 800HV was generated. The thickness of the hardened layer is 20µm to 40µm.

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Drilling of the carburized part is can generated compressive residual stress on the machined surface. The compressive residual stress expected to improve mechanical properties such as the fatigue life and the resistance to stress corrosion cracking. In this study investigated relationship between spindle speed, residual stress, work hardening and state of hole after drilling. As result, spindle speed increased compressive residual stress on the machined surface decreased. Therefore, the spindle speed can control generated compressive residual stress on the machined surface. Then we discuss the controllability of such mechanical properties of the machined surface with the setting of the spindle speed.

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The truncation of surface asperities is considered to prevent excessive wear at the initial stage of sliding contact. In this paper, the effect of truncation on rough surface contact without sliding is examined. Surface profiles during a truncation process were simulated using numerical method based on autoregressive process and two–dimensional numerical analysis of elastic contact was conducted. The calculated results showed that real contact area increased and asperity contact pressure decreased against the same nominal pressure with the progress of truncation. It indicates that truncation is a significant factor of contact behavior.

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To prevent the falling accidents, not–slippery floor materials are required. The evaluation method of slipperiness in the past did not considered the effect of sliding velocity on the friction coefficient. Thus, the dynamic characteristic of friction was not taken into account. In this study, the tribological properties of textured FRP floor surfaces, including the effect of sliding velocity, were investigated in dry and wet condition. It was found that micro–textured surface has good properties because not only the drop of friction coefficient in wet condition became small, but also a tendency was observed where the friction coefficient increases with the sliding velocity.

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The aim of this study is to propose an internal magnetic abrasive finishing process for nonferromagnetic fittings, which do not have rotational symmetry and fine finish is therefore considered difficult to achieve by conventional technology. This paper presents the finishing principle and the finishing equipment, which provides flexible motion of a finishing unit by means of a 6–axes controlled robot. The finishing experiments of SUS304 stainless steel fittings characterize the effects of the size of ferrous particles, mixed with either WA magnetic abrasive or WA abrasive, on the dynamic motion of the particles as well as the magnetic force. The material removal characteristics vary as the size of the ferrous particles affect the area of finishing and the depth of cut of the WA magnetic abrasive or WA abrasive. Accordingly, this study concludes feasibility of the process for improving the roughness and unevenness of the internal surfaces of the fittings.

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This research examined an improvement of the form accuracy (Roundness) on internal magnetic field assisted finishing process using a magnetic machining jig. The rotation speed of the magnetic processing jig was set to 150min–1 and 250min–1 with SUS304 stainless steel tubing, and the finishing experiments were carried out. As the results, the roundness of inside tubing can be improved against both experiments, the processing characteristics were influenced by the rotation speed, and it was clarified that a good result was obtained in the case of 250min–1 at the rotation speed.

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The purpose of this study is to finish the die with 2D groove produced by wire cut electric discharge machining. Then, workpiece oscillation type magnetic field assisted machining method which gave oscillation in groove direction was adopted. With this processing method, it is expected that surface is smoothed, while edge shape is maintained. Generally, die material is often magnetic material. In magnetic polishing of magnetic material, polishing tool remains on surface of workpiece by magnetic attraction, and there is a problem that sufficient relative motion is not obtained on machined surface. In this study, surface polishing of magnetic material was examined using workpiece oscillation type magnetic field assisted machining method in order to solve this problem.

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By previous report, we polished inside of a square tube and corner R by letting a corner tube vibrate with mixed type magnetic abrasives. There are internal 2.5 times, and surface roughness of bare tube corner R is a rough surface. However, the abrasion side coarseness of best corner R was 0.042μm Ra.
This study polishid it by mixture type of stainless steel pins and magnetic abrasives newly for the purpose of improving the finish side of corner tube corner R. As a result, the finishing time got the best surface roughness 0.025μm Ra in five minutes.

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Previous work developed a new type of magnetic finishing tool–MRF–based slurry–and demonstrated its application to the internal finishing of SUS304 stainless steel tubes. The aim of the present study is to clarify the effects of abrasive types included in the MRF–based slurry on the characteristics of the internal finishing process of SUS304 stainless steel tubes. In addition, the applicability of MRF–based slurry to the internal finishing process for slender tubes is discussed. The experimental results showed that both of the MRF–based slurries, which include WA abrasive or diamond abrasive, achieve smooth finished surfaces. Specifically, the MRF–based slurry with diamond abrasive generates smooth finished surfaces with less directional cutting marks than the MRF–based slurry using WA abrasive. Moreover, the finishing experiments found the applicability of the MRF–based slurry to the internal finishing of slender tubes.

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Magneto –rheological Finishing (MRF) was applied to nano–precision finishing of silicon wafer. Several sets of finishing experiments for silicon wafer have been performed to verify obtainable surface roughness and removal rate. Influence of some process parameters such as wheel rotation, magnetizing current, immersed depth and MR fluids viscosity on removal rate were investigated. The surface micro–roughness less than 10 Angstrom for silicon mirror were produced.

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Authors have proposed to apply the high precision processing technology for the medical products. Terefore we are aiming at the new device development that has a low cost and high reliability. This research develops a new processing technology that uses abarasives control technology under the electric field and executes a basic research to obtain the microchannel requested from μTAS. It was able to be clarified to give the processing to the glass that was the construction thing the tool was developed, the abrasives functional fluid was given to the surroundings the tool was rotated while under AC electric field.

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The challenge and opportunity in Korean CMP technology are becoming more active, resulting from the severe processing requirement by the dramatic change to nanopattern structures and mobile devices. Therefore, Korean device makers need more sophisticated CMP equipment, new consumables with scientific concept and analysis tool based on fundamental understanding. Recent developments by Korean CMP equipment, consumable developing company and university are introduced for making better understanding and relationship between Korean and Japanese CMP members .

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Pad surface modification influence on removal profile change was evaluated under no–conditioning process. Pad chemical modification by FT–IR analysis was focused on the quantification of the pad surface condition of pad surface. The radial pad modification corresponds to the radial wafer trajectory density on pad surface. The radial distribution on pad modification was transformed into the radial integration profile on a wafer. As the result, it was demonstrated that radial integration profile of the pad modification on the wafer was a good agreement with the actual removal profile accurately.

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For an investigation on dominant factors of pad surface function, removal rate recovery was evaluated by means of various pad treatments without surface scraping using no conditioning pad. The most recovery–ratio on removal rate was 31% at most under the most effective brushing treatment regardless of the elimination of polishing by–products in pad pores. The results suggested that it is necessary to scrape off pad surface layer for pad conditioning. Based on both the recovery evaluations on the pad and the specifications on CMP conditioner, a noble deflecting conditioner was developed for an effective pad conditioning. Consequently, it was demonstrated that the conditioner realized uniform conditioning with no relationship of long range of height variations on the pad.

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In this study, generating behavior of grain cutting edges by dressing for a pyramidal structured polishing pad has been investigated. A series of dressing tests has been carried out and the variation of cutting–edge shapes has been analyzed continuously. As a result, it has been shown that the dressing using the polishing fluid containing loose abrasives with a diameter of 1μm is effective in order to generate suitable grain cutting edges.

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In this work, Dual Emission UV–Enhanced Fluorescence (DEUVEF) technique was used to measure the amount of dyed slurry residues inside the pad grooves to evaluate the efficacy of the conventional diamond conditioning and High pressure micro jet (HPMJ) conditioning. In case of using HPMJ conditioning, the fluorescence intensity inside the grooves of pad decreased dramatically with the every conditioning time for K–groove and XY–groove comparing diamond conditioning. These experiments indicated that the HPMJ provided more effective pad conditioning for the removal of slurry residual from the pad grooves. HPMJ will be able to decrease defects like micro scratches from slurry residues in real industry.

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During polishing a device wafer by CMP equipment, vibration of Top–ring assembly that holds the wafer sometimes occurs in some polishing conditions. This vibration causes large noise, and introduces vibration of whole equipment. Therefore, it is important to know conditions of vibration outbreak and methods of preventing vibration for designing and operating CMP equipment. The results of the investigation showed that the vibration was unstable vibration that was caused by stick slip vibration generated by friction between a wafer and a pad. This report shows examples of reducing the vibration of CMP equipment by calculating relationships between eigenvalue of the Top–ring assembly and stiffness of Top–ring assembly members.

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[in Japanese]

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The lapping method is frequently used for making high precision surface finishes, and the waviness reduction in lapped wafers needs to be improved. Moreover, it is known that the 4–way system is generally used in the lapping method. However, the 4–way system has some problems, therefore, the method which uses the small diameter tool and controls the tool oscillation are presented in the polishing technique. This study presents the basic characteristics of the oscillated control lapping method. The basic experimental and numerical results on this method are shown in this report.

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The polishing slurry for silicon wafer usually uses the colloidal silica particles. The colloidal silica works as the mechanical polishing. It has the important item of the various polishing factors. There are many type of silica as to size and shape. It is selected according to the purpose of polishing.
The investigated items in this time are the polish rate, surface roughness on the wafer and the friction between wafer and pad during the polishing. As the result, the surface roughness had the relationship of the particle size, and in addition, the friction showed the unique data at 10nm size silica slurry. It was related the action of silica particles and the roughness on the wafer and pad at the beginning of polish.

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Monitoring system for CMP equipment, which uses friction force and temperature measurement, was newly developed. The correlation between friction and CMP results can be investigated in terms of the tribological aspects by using the monitoring system. Therefore, the removal mechanism of materials could be understood through the investigation of correlation between removal rate and coefficient of friction. In this study, a close examination between friction and CMP results was conducted. The results show that the material removal per unit sliding distance is proportional to friction force with regard to polishing performance. The friction energy affects removal rate and process temperature. Also, within wafer non–uniformity increases with the coefficient of friction, because operating location of normal resultant force on wafer shifts to its edge. Therefore the monitoring system will contribute to research and development of CMP process for fabrication of semiconductor device and silicon wafer.

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Effect of pad surface roughness on SiO2 removal rate was investigated by using four slurries with ceria particles of different crystallite size and mean particle size (D50%). A clear maximum was observed in the dependence of removal rate on pad surface roughness, regarding both blanket and patterned wafer polishing. The four ceria slurries showed peaks in removal rate against pad surface roughness, Ra. The peak moved toward larger Ra value with decreasing crystallite size of ceria.

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The cerium oxide particles of single crystal were obtained only by the combination of precipitation method and hydrothermal treatment at lower temperature than 200-C. The particles showed plate–like shape even in the particle size of about 4 nm. By heating, the particle size was increased from about 4 nm to 60 nm maintaining the plate–like shape with elevating the temperature. These cerium oxide particles were applied as a fine abrasive grain for mirror grinding. We manufactured a grinding pellet, consisted of the plate–like cerium oxide particles, using electrophoretic deposition (EPD) phenomenon. As a result of grinding of quartz–crystal wafer using the ceria EPD pellet, fine mirror surface with roughness less than 1nmRy was realized.

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We present the dispersion stability of cerium oxide CMP slurries as functions of adsorbed amounts of PEO and PVP as well as the average diameters of the particles adsorbed by the corresponding polymers. We also investigated the polishing properties of Si wafers by the slurries before and after re–dispersed in water. The resulting average diameter increased with increasing the adsorbed amount of polymer for PEO and PVP. PVP enhanced the dispersion stability of the cerium oxide CMP slurries in comparison with PEO due to its thick adsorbed layer. The difference in the polishing strength of the wafers can be interpreted by the re–dispersion of the slurries in water.

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The copper damascene technique with chemical mechanical planarization (CMP) is the most suitable approach to achieve high–performance multi–level interconnects using low–k materials. The primary objective of the Cu–CMP process is to reduce the defects such as dishing, scratching and erosion, which are partially due to hard inorganic abrasives or low selectivity of copper to barrier metals and dielectric materials. Recently, we have developed novel Cu–CMP slurries based on pure organic particles acting as abrasives to improve those defects using functional polymer resin technology. These soft polymer abrasives have reactive layers to copper on the surface and they work effectively when the abrasives are deformed. As a result, we have achieved high planarization and low defects.

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Chemical Mechanical Polishing(CMP) is essential for the manufacturing of recent high–performance electronic device. However, for the CMP process,huge amount of slurry is used, which is to be disposed after being used only once. From the viewpoint of reduction of environmental burdens, this study was made for exploring the possibility of recycling of slurry by focusing on the slurry used for W–CMP. For that purpose, we collected the slurry used for polishing and then tried to reuse it for polishing again. As a method for evaluation, We made comparisons of removal rates between fresh slurry and reused slurry. The results shows that when collecting the slurry during CMP,it contained the water remained on the surface of the polishing pad after dressing, by which slurry was diluted and caused the reduction of removal rate of W–film. However,it was found that when making polishing of W–film using the slurry reused without being diluted with water, the same level of removal rate as fresh slurry is obtained.

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In this research, the ultraviolet–exposing type polisher is fabricated for accomplishing the polishing experiment of copper. This paper also describes the polishing characteristics of copper which ultraviolet ray is exposed on.

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In Four–Body Finishing, an emerging polishing method in which polymer particles, called Carrier Particles, are employed and the edge profile of workpiece can be controlled, polystyrene particles exhibits relatively excellent polishing performance. The polystyrene particles, however, differ from each other in terms of various properties, depending on their process of manufacture, as well as raw materials and chemicals used. In this report, with the purpose for process optimization, several kinds of polystyrene particles are compared based on silicon polishing experiment, and the relation between their polishing performance and properties are examined for appropriate carrier particles selection.

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Not only the corrugation wear of railroad causes vibration and noise, but also it is mentioned as one of the factors which are connected with the derailment. Till now, as this corrugation wear countermeasure, the face grinding has been used for the re–plofiling method. However this method is indicated to be inefficiency and it is difficult to keep the rail smoothly. In this study, the platen polishing with ML (Multi–Layered) belts is noticed for the new efficiently method, and ML belt polishing is tried to apply to the rail re–profile.

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