Porous low-k materials are required in the construction of LSI devices. However, the extremely low Young's modulus values of these materials result in peeling and/or stress corrosion cracking (SCC) of Cu interconnects during chemical mechanical planarization (CMP). We performed finite element method (FEM) analysis of stress during each step in CMP processing varying Young's modulus of interlayer dielectric (ILD) films. The results supported that the horizontal tensile stress concentrated especially at the edges of the isolated fine wiring, and that higher tensile stresses appeared at the step of barrier CMP. Moreover, the maximum values of tensile stress increased with the decrease of Young's modulus of low-k films. Shear stresses also increased with the increase of the difference of Young's modulus between materials. Since the cause of these stresses are due to the downward CMP pressure on the hard material (e.g. Cu) and the soft material (e.g. low-k film), which indented the soft materials, CMP process with a lower downward pressure and a structure with dummy pattern is recommended.

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The material removal mechanism of Chemical Mechanical Polishing has a lot of unidentified aspects which are not yet clarified. Moreover, it is very difficult to build up the systematic simulation system on the mechanism. It is indispensable to model the contact mechanism among abrasive particles, surface of wafer and surface of polishing pad in order to construct a simulation system in CMP. However, the conventional modeling of polishing pad surface is not appropriate for the simulation. In this research, by observing the surface of the polishing pad, a model of the polishing pad surface was proposed. Further, the relationship was considered between the surface structure of polishing pad and material removal mechanism.

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Cu-CMP process shifts to high speed/low pressure process. To decrease the polish time and improve the planality of film thickness on wafer, 2 step polish should be required. 2 step polish means that 1st step is high pressure process to decrease the polish time and 2nd step is low pressure process to decrease the dishing and erosion. To solve this problem, we report eddy current EPM that can monitor the change of metal thickness and detect endpoint of CMP.

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Magnetic bearing technology is applied to a CMP wafer head to control the polish rate profile by tilting the wafer head during polishing. If no control is applied, the wafer head subsides slightly into the pad and is tilted 18×10^<-5> rad by the viscoelasticity of the pad. Tilting the head to the positive side can increase the polish rate in the wafer outer area ; tilting it to the negative side can reduce the polish rate of the wafer center area. It has been reported to be possible to improve the polish rate profile by keeping the wafer head in a horizontal position using a magnetic control. Magnetic control is available to the over hang polishing. Over hang polishing is useful for the reduction of footprint and in-situ film thickness monitor.

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Flow characteristics of diamond particle dispersion type functional fluid impressed high AC voltage were investigated to improve a new polishing technique for nano-microscopic processing technology. This study evaluated the influence of electrode distance on flow characteristics. This functional fluid has some types of flow structure in microscopic flow field. One is the flow going and returning between the electrodes under the low electric intensity and the high AC frequency conditions. The other is the forced convection under the high electric intensity and the low frequency conditions. This forced convection is consisted of some rotational flow structures changing alternately the positive and the negative vorticity concentrations generated at the fixed time after impression of rectangular AC wave. These flow characteristics do not depend on the electrode distance but on the electric field conditions.

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In late years, a group of minuteness sensor corresponding to this and minuteness sensors to clarify minuteness structure of a flow is demanded as miniaturization of a measurement device advances. I develop micro shear stress sensor that it aimed for the measurement and control of a flow of a heat fluid by this study. Based on silicon, I examine a production process of a metal film or semiconductor film of the minuteness sensors that assumed a resistance sensor. And made a prototype in this school clean room, I report the summary here.

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The semiconductor microfabrication technology is provids remarkable advancement. A scale-down electronic equipment and a fuel cell with high effectiveness are actively developed. In this research, a micro channel made by applying the semiconductor processing technology. The experiment the diffusion coefficient of the soda water in microchannel was conducted by using micro LIF method. The soda water is dissolved one of two liquids that thoroughly mix dyestuff. The diffusion coefficient of the soda water was measured by the pH with Y type microchannel with two entrances and two exits.

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A simple design micro-heat pipe was proposed. It was composed of 20.0×20.0mm square flow circuit which had two adjacent narrow-sides (1.0×1.0mm^2 or 0.5×1.0mm^2) and two adjacent wide-sides (5.0×1.0mm^2 or 2.5×1.0mm^2). A heating spot was at the narrow side and a cooling spot was at the wide side. Working fluid was ethanol. The flow circuit was placed horizontally. It was confirmed that heat transport from the narrow-side heating spot to the wide-side cooling spot was produced in the micro heat pipe. An analysis of a flow mechanism was performed by solving a simple flow equation based on the flow resistance. It was proved that one-way circulation flow could be formed in the flow circuit. Predicted flow velocities were close to measured velocities. The heat transport efficiency per unit mass of the proposed micro heat pipe was much better than the heat conduction-type heat transport device of any metallic plate.

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Scaling trends for current and future ULSI interconnects, and issues of performance, integration, and mechanical reliability are addressed in this paper. Wiring size reduction according to the scaling rules needs to introduce Cu/Low-k technology to prevent the capacitance increse. However, the weak mechanical properties of the low k materials will degrade the mechanical reliability of Cu interconnects. During chip fabrication and package assembly, chemical mechanical polishing (CMP) and die attach are two processes where significant stresses can be imposed onto the low k chip, raising serious reliability concerns. It is necessary to address these issues intensively.

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In this paper, a selective absorber thin film is proposed for the energy absorber thin film of a laser micro actuator used as an actuator in a micromachine. The selective absorber thin film is composed of a germanium thin film and silicon oxide thin film deposited on a alminum substrate and is fabricated by vaccum deposition. At the first stage germanium and silicon oxide are deposited on a glass substrate, respectively for estimating deposition rates and determining the characteristics of a deposited thin film. At the second stage selective absorber thin films that have different film thickness combinations are made and moreover, optical properties and surface temperature with laser irradiation are measured to decide the optimal film thickness for optical laser.

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Some types of polymer actuator have recently been focused. These actuators which are soft-structured and operated in wet condition- are so called Artificial muscle. IPMC-Ionic polymer and metal composite, one type of artificial muscle, is one of the simplest actuator. This is a binding of ion exchange membrane (IEM) as a solid electrolyte and metal thin film as electrodes. This actuation, provides a bending motion, is involved by the stress called swelling pressure. Swelling pressure is the sum of osmosis pressure and fluid pressure powered by internal ionic movement. In this paper, we have evaluated the relationship between shape or area of electrodes bit into IEM and actuation specification.

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Supercritical fluid is a high-pressure medium that possesses unique features such as solvent ability and nano penetration capability. Dissolving organic metallic conpounds in Supercritical fluid enable to depositon Cu thin films. We have developed a continuous flow reaction system that controls deposition parameters precisely. We recently succeed in improving H_2 gas mixing unit. In this paper, we discuss the effect of H_2 addition on deposition characteeristics.

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The purpose of the present study is to develop a sensor for evaluating the reusability of structural parts under cyclic loading. The basic principle of the sensing is the accelated fatigue damage of the sensor with induced residual stress by ion implanting technique. In the present paper, a new experimental method is proposed for the thin specimen, and the relationship between Fe ion implanting and fatigue damage (crack initiation) is experimentally investigated.

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Flash lamp annealing is one of technologies for wafer heat treatment proposed as the next generation. However, problems such as wafer breakages sometimes occur because of large thermal stress inside of wafers. In order to identify the mechanism of the breakage, we simulated thermal stress during flash lamp annealing by a finite element method analysis. The results of the simulation showed that compressive stress could occur at a front surface and edge regions of a wafer, and tensile stress could occur at a back surface of a wafer. In addition, maximum compressive stress of 450MPa could occur at the center of the front surface. In the case of tensile stress, maximum value of 170MPa could occur at the center of the back surface. Also maximum shearing stress of slip direction, which was 225MPa, could be around the vicinity of a start point of the edge region of front surface.

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This paper shows the analysis results of delamination toughness in interconnections made by the dualdamascene method during planarizing processes by CMP (Chemical Mechanical Planarization). Mechanical properties and dimensions of interconnect structure in the future technology-node are predicted, and strain energy densities are calculated by finite element analysis under down-forces and frictions of CMP processes. Estimating equation of critical energy release rate of the low-k material interface is derived, and evaluated for the comparison with the calculated strain energy densities. The results of analysis show that the interface of the hardmasks and trenchs is most concerned parts about delamination and the delamination toughness are affected by Young's modulus of the low-k materials of interface. However, it is also shown that the delamination toughness under the realistic transition of Young's modulus for dielectric constants are maintained into the future.

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Semi-active control for civil structure has been studied recent years, because it achieves as high performance as active control with less energy consumption. However, nonlinear characteristics such as hysteresis loop of a semi-active control unit make the control system design difficult. While control method taking account of nonlinear characteristics has not been established yet. This research proposes a new design method for semi-active optimal control system. We use a MR damper as an actuator and apply a nonlinear control theory taking account of the nonlinear characteristics. In this method, the optimal, damping coefficient for the MR damper could be explicitly obtained without "clipping". Proposed approach is applied to vibration control of multi buildings connected with the MR damper. Effectiveness of the presented controller and MR damper is examined through simulation and experiment under random and earthquake wave excitations.

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In this report, a new device called pendulum tuned mass damper (PTMD) is proposed to reduce the vibration of three story houses. In recent years, three stories houses are built increasingly in the urban areas to obtain wide living space in a narrow land area. These houses are subjected to numerous vibration problem caused by the traffic vibration To solve this problem, damper (PTMD) acts on the principle of lever mechanism and this requires a small tuned mass. This is also cost effective and can be placed between the first and second floor. The vibration control results are verified through simulation and experimental studies.

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This paper deals with verification control effect by shape change in vibration control arms. The control objects are flexible plates like solar array panels. Two flexible plates are connected with each other through the electromagnetic actuators fixed with the flexible arms. As a vibration control mechanism, the method using the interactive force between structures is applied for vibration control of these plate structures. To examine the best arm type, control effects by changing arm positions and shapes are compared.

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This paper deals with seismic response control of two identical structures in parallel. One of the authors had already proposed connected control method for vibration control of flexible structures arranged in parallel. However, its control performance degraded as the natural frequencies of structures become closer. Therefore, the authors have presented a modified control mechanism in which the actuators are connected to the structures with a difference in its connecting position using long arms. Its optimal design strategy of vibration control device is established by previous study of authors. In this report an effectiveness of the seismic response control of two identical structures is demonstrated using connected control method.

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For thin steel plates which are used in many industrial products including those of the automobile industry, we have proposed a magnetic levitation control system and confirmed its realization by means of the digital control experiment. However, in the case in which only the levitation control is applied to the steel plate, it has no horizontal restraining force on the direction of travel. Therefore electromagnetic actuators are installed in order to control the horizontal position movement of the levitated steel plate. The electromagnetic attractive control forces of the actuators are given for the two facing edges of the levitated steel plate, from the horizontal direction. In this paper, the suppression effect of bend of ultra-thin steel plate in the horizontal noncontact positioning control is reported.

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This paper deals with motion and vibration control for a flexible tower-like transportation system, using piezoelectric film senor In order to control the vibration of the transportation system with long distance moving, it is necessity to detect the vibration without limitation. For the propose, the piezoelectric film paste on the structure is used as the point sensor. Applying a lumped modeling method presented by Seto and LQI-based control system, two controllers are designed which achieves good performance for controlling motion and vibration in the flexible transportation system. Moreover, a possibility using the piezo film as a point sensor for vibration control is examined.

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This paper proposes new modeling technique and control system for multiple modes vibration control of a flexible rotor supported by active magnetic bearings. The purpose of our study is to rotate a flexible rotor with high rotation speed that exceeds critical speed of the second elasticity mode. To achieve this, vibration as well as motion has to be controlled. According to this purpose, new modeling technique named as "extended reduced order physical model" that can express both motion and vibration simultaneously is presented. Using this model, a PID controller to levitate the rotor and a LQ controller to suppress vibration of the rotor are designed. The performances of these controllers are examined through computer simulation.

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Surface acoustic wave (SAW) linear motor is a kind of ultrasonic motors. The advantages of the SAW linear motor is thin structure, high thrust force, high velocity and precise positioning. Relationship between applied voltage and output velocity, however, has non-linearity in a low-velocity area due to friction drive principle. Therefore the SAW linear motor cannot obtain stable driving without feedback control in the low-velocity area. Previously, to realize such low velocity, PWM control and flexible slider structure were employed. Flexible structure was installed to cancel vibration due to PWM carrier frequency. In this research, we change calculation algorithm for slider velocity measurement. As a result, SAW linear motor can be driven at a low velocity of 0.05mm/s.

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A new repulsive-type magnetic bearing system is developed which uses the motion control of a permanent magnet for the stabilization of an axial motion and two radial motions. The developed actuator units for motion control are studied experimentally. Stabilization is tried when the motion of the floator is mechanically constrained.

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This paper proposes a design method of a three dimensional isolation system with a low stiffness isolation table assumed as large-size and lightweight isolation system. In large-size and lightweight isolation table, multi vibration modes appear on an isolation table in lower frequency region. Owing to this, we construct the 5-DOF lumped mass model using a reduced order physical modeling method, which is effective for controlling multi modes vibration in the vertical direction. In controller design, two-degree-of-freedom controller combining feedback controller with feedforward one is designed. In this paper, effectiveness of the feedforward control with multiple inputs on the isolation performance is demonstrated.

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A vibration isolation unit with a weight support mechanism is developed for an active vibration isolation system using a parallel mechanism. The basic characteristics of the unit are measured for designing the zero-power controller. The zero-power control was achieved in the developed unit. It is experimentally shown that the unit has high stiffness against s static direct disturbance.

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Recently, influence of micro vibration on precision machines is increasing in many high technology fields such as semiconductor manufacturing. Therefore, active vibration isolation devices equipped with air actuators and sensors come into use for the micro vibration control field, and these active vibration isolation devices have achieved good vibration performance. Recently, active vibration isolation devices are required in very strong magnetic field such as NMR. In conventional devices, the servo valves which provide actuators with air are set up on actuators directly. However, in strong magnetic field, servo valves need to be separated from actuators by using long pipes to avoid the effect of magnetic field, and this long pipe changes the dynamics of the device itself. In this study, simulations and experiments are conducted for the above vibration isolation device with long pipe system, and the effectiveness of the proposed MM control system is verified.

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The clutch is slid for a short time at the engaging the gear of a manual gear car. The self-excited vibration might be generated at this time, and this is called clutch judder. The simulation model of clutch judder is studied here to clarify the relation between the clutch characteristic and clutch judder. First, the validity of the model is examined compared with a past analytical model. It is confirmed that the stability area and the frequency response of the simulation model are corresponding to an analytical model. Here, in addition, the simulation model of the FR car is made, and the relation of slip and clutch judder in the FR car is verified.

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In this paper, a control method for shifting of gears of a four-wheeled vehicle with a manual transmission is proposed for. 10.15 mode automatic driving on a chassis dynamometer. The control system consists of three actuators for the accelerator, the clutch and shifting the gear. The control inputs for the accelerator and the clutch are obtained by applying final-state control with error learning for a simplified two-inertia model of the vehicle. It is verified from the test results on the chassis dynamometer that shifting of gears by the control system proposed is effective.

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Recently, motion simulators such as flight simulators and driving simulators are widely used as "operation training tool" or "evaluation tool for new system development" in various advanced mobility fields. However, it often happens that inertia force which is made by the motion simulator is not sufficient compared to real system especially in high frequency range, because, in general, it is difficult to realize precise motion in high frequency range. In this study, we propose the control system design technique for the motion simulators using Dual Model Matching (DMM) in order to attain precise reference following performance of the motion simulator in high frequency range. Effectiveness of the proposed DMM control system is verified with both simulation and real experiment using the Stewart Platform type flight simulator in Japan Aerospace Exploration Agency (JAXA), by just replacing the conventional controller with the proposed DMM controller.

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The purpose of this study is to examine the effectiveness of active seat suspension when it is applied to small cars and the problems associated with its practical use. A small active seat suspension is installed for one-seater electric automobiles. In an actual driving test, a test road in which the concavity and convexity of an actual road surface were simulated using hard rubber was prepared. In this paper, we aim to develop a vibration isolation system of the driver's seat with high robustness using the sliding mode control, which is tolerable to factors such as variation of parameter variations of a motor. Experiments were carried out for several conditions, and the obtained results were compared with optimal control results. As a result, it was verified that the suppressive effect of the sliding mode control on the vibration isolation was confirmed.

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Over the last ten years, the National Research Institute for Earth Science and Disaster prevention (NIED) had been constructing a shaking table facility, known as E-Defense. E-Defense was completed in March 2005, and its operation started in April 2005. The Hyogo Earthquake Engineering Research Center was established on October 1, 2004, to manage research projects using E-Defense and to operate as well as to maintain the facility. E-Defense has the unique capacity to experiment with life-size buildings and infrastructural systems in real earthquake conditions, and stands as a tool of ultimate verification. With this feature, E-Defense should help expedite the transfer of various research outputs into the practice of earthquake disaster mitigation. This study shows shaking performance of E-Defense with test structure.

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The vibration on the riding comfort of automobile vehicle is simulated. Main parts of the vibration on the riding comfort are modeled, and are analyzed. In the suspension modeling, the effect of the friction is studied, and In the engine mounting modeling, the effect of the position is studied. In the car body modeling, modal analysis in FEM is used. The simulation analysis is carried out using the passenger car model. In addition, the vibration reduction method is examined by the parametric study.

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