Porous low-k materials are required in the construction of 45nm-node LSI devices. However, the extremely low Young's modulus values of these materials result in SCC (Stress Corrosion Cracking) of Cu interconnects during CMP processing. We performed FEM (Finite Element Method) analysis of stress during each steps in CMP processing. 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 Cu clear CMP. Moreover, the maximum values of tensile stress increased with the decrease of Young's modulus of low-k films. Since the cause of horizontal tensile stress is due to the downward CMP pressure on the hard surface (Cu) and the soft surface (low-k film), which indented the low-k films, CMP process with a lighter downward pressure and a structure with dummy pattern is recommended.

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A relationship between allowable initial Peak-to-Valley heights (allowable PV) of a nanotopography and selectivity of slurry for CMP process making STI was analyzed quantitatively using a simple simulation method. The results show that the allowable PV became larger according to an increase of the selectivity. Moreover, in the case of the selectivity of thirty, the allowable PV were four times to eight times larger than the case with the selectivity of three. However, it is noted that the slurry for the process should have the ability of performing not only high selectivity but also small dishing.

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This paper shows analysis of stress in inter-connected structures made by dual-damascene method during planarizing processes by CMP (Chemical Mechanical Polishing). Mechanical properties and dimensions in the future generations of inter-connected structures are analyzed. Von Mises equivalent stresses are calculated by Finite Element Method under down-forces and frictions of CMP processes. The results of analysis show that maximum stress is observed at the intermediate positions of vias and depends on the Young's modulus of the Low-k material. However, the maximum stress in vias at the 32 nm-node is only three times as large as the stress at the 90 nm-node.

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A laser opto-microactuator has been proposed as an Optical Micro-Electro-Mechanical-Systems (OMEMS). The rotational or twisting mechanisms of the micro actuator have been discussed. In the present paper experimental and numerical approaches have been carried out. For increasing the absorption rates of a laser beam on the blades of the micro actuator, carbon molecules were deposited from a heated carbon fiber to substrates in a vacuum deposition machine. The deposition rates were experimentally measured and are compared with the numerical results by DSMC.

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Supercritical fluids is a high-pressure medium that possesses unique features such as solvent ability and nano penetration capability. Using supercritical CO_2 fluids as a medium for thin film deposition provides excellent gap-filling and step-coverage possibilities. Lacking of the information of pros and cons and deposition characteristics exists due to the novelty of this technique. One of the reason for that is no presence of deposition tools sophisticated as much as existing deposition techniques such as CVD. We have recently developed a flow-type deposition tool that enables continuous supply of a metal precursor with fixing the deposition parameters. This paper reports quantitative discussion of deposition characteristics of Cu thin film growth using the flow type reactor.

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Material removal mechanism in CMP process is complicated phenomena and it is difficult to analyse quantitatively because of combined chemical and mechanical processes. Recent analysis on CMP material removal is based on the action of fine particles in slurry. However, it is considered that particles work on wafer surface equally, thus material removal on wafer surface occurs uniformly and it is difficult to predict material removal distribution on wafer surface. For analysis of material removal distribution on wafer surface, variation of polishing distance generated by the motion of CMP machine structure and machine motion conditions has to be considered. On the report, the influence on polishing distance for material removal in CMP process is investgated.

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Nodular colloidal silica is proposed to be used as a consumable material for the CMP. The typical spherical colloidal silica slurry is effective in decreasing the defect level of the interlayer dielectric (ILD) film during CMP, but the removal rate is also decreased. Hence, the nodular colloidal silica slurry has been developed for the purpose of improving the performance on CMP process. The surface characteristics of the silica particles are considered to affect the removal rate of ILD film and the planarity of W CMP process etc. These CMP performances are recognized to depend on the different characteristics between the spherical colloidal and fumed silica.

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This paper proposes a control method against a direct disturbance acted on an active isolation system with a low stiffness and lightweight isolation table. A large-size isolation table needs to reduce the weight per size, and then multi vibration modes appear on the isolation table in lower frequency region. For controlling the multi-mode vibration, the 5-DOF lumped mass model using a reduced order physical modeling method and LQ control theory are adapted. In order to control the direct disturbance on the table, a feed forward controller is designed. Usefulness of proposed modeling method and controller is confirmed through experimental results.

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Proteins were immobilized on the inner wall of Polymeric micro-channels using both photo-chemical reaction and physical adsorption. Photochemical procedure enabled the accumulation of protein functions in a very small space of the chip by the immobilization of several enzymes as well as antibodies. In this lecture, some example of the device will be demonstrated. 1. Bovine serum albumin was first adsorbed on the PDMS micro channel, then Glucose oxydase (GOD) and HRP modified with photo-chemical cross linker (ATFB-SE). which had both photo-reactive moiety at one end and amine reactive group at the other was immobilized on BSA at the different position of microchannel. The chip detected glucose by the following scheme: glucose+oxygen+GOD gave glucronic acid+hydrogen peroxide, then hydrogen peroxide+HRP+Amplex red gave Resorufin (highly fluorescent). The similar procedure gave immune reactive sensor chip.

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We have proposed a catalyst fabrication process which using ion implantation and surface etching (IISE), apply to the micro chemical system like micro total analysis system (μ-TAS). IISE can use the advantages of ion implantation, which are select ability of ion species and area, and control ability. Because, it is possible to support many kind of catalysts on each devices as the need arises. In this paper, we try to compare a different of ion energy of 3MeV and 75keV, which relate to a ion distribution of depth. A result, a case of 75keV ion implantation make a larger nano-particles than 3MeV, and the number of particles are smaller. This is similar to the lower dose case of 3MeV. Though, it seems that the KOH solution was etched over the shallow implanted layer and implanted seeds ions are released to the solution.

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Ink jet printer technology is applied to general industrial equipment recent year. With an increase in the gap between the head and the carried paper of the printer, it is necessary to clarify the effect of the paper velocity on the trajectory of an ink jet droplet in order to do the high-speed and the accurate printing. In this paper, the behaviour of an ink jet droplet has been studied experimentally by means of a Piezo type drop-on-demand ink jet printer. The gap between the head and the carried paper is 3mm, and the carried paper velocity was set at 0.4m/s. Numerical simulations carried out the trajectory of the droplet by considering to the effect of the paper velocity. It was seen that the analytical results agree well with the experimental results.

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A wettability-pattern, array of hydrophobic and hydrophilic regions, is formed on Si substrate. The shape and sliding angle of water drop were experimentally investigated for some types of stripe wettability-patterns. At the both edge of water drop on the stripe wettability-pattern, headland-like water films are formed on the hydrophilic regions. The radius of the water film becomes larger as line width and number of hydrophilic region under water drop are increased. The sliding angle also changes with design of wettability-pattern and falls with rise of the ratio of hydrophilic width to hydrophobic width. Then, the wettability-patterned substrates were fished up from a suspension containing polystyrene micro spheres. The micro spheres were self-aligned on the hydrophilic regions to be hexagonally packed into monolayer after forming a quasi-aligned state along the edge of headland-like water films. A width of aligned spheres changes with both hydrophilic and hydrophobic widths, so that it seems to be affected by three-dimensional shape of water films like a practical contact angle.

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This research aims to investigate how the tool roughness influences the formed cup accuracy and forming characteristics in micro-cup drawing and to collect the data for a micro-die design guideline. In this paper, a specially designed micro deep-drawing machine system is developed to control a very small force applied on blank holder and punch during the deep drawing process. Stainless steel and phosphor bronze thin sheets of 20μm thickness are used in the experiment. The die cavity diameter for cup drawing is 700μm. Experimental results with several tool conditions show that the developed machine system has enough forming characteristic performance for micro forming and tool positioning accuracy significantly affects the forming characteristics in the micro forming process.

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In this paper, fabrication process of microtube using superplastic dieless tube drawing is studied experimentally. Superplastic material used is Al-78Zn (SPZ) alloy tube with outer diameter of 2mm and wall thickness of 0.5mm. A high-frequency induction heating apparatus with air cooling nozzle is used for the dieless drawing. In the experiment of three-pass dieless drawing, a microtube with outer and inner diameters of 343μm and 161μm, respectively can be fabricated successfully. In addition, from the experimental results, it is confirmed that the ratio of inner to outer tube diameters maintains a constant value in the dieless drawing. In other words, the geometrical similarity with the minimization of dimension is satisfied.

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This paper describes high performance microactuator and microvalve for micropump fabricated by metal-forming process. The process has advantage of process cost, time, throughput and degree of freedom compared to SC process. Additionally, in recently years, it can manufacture micro devices (μm〜) using such as microassembly in progressive die and laser process, and effective in the area of micro fluid devices which need to be disposable because those devices treat bio-fluids. We proposed high performance microactuator and microvalve by metal-forming which be able to 3-D process. The former is of 3-D dome bi-metal which give rise to buckling. The displacement of 3mm diameter and 0.07mm thickness reached to about 570μm The later is thin metal cantilever with 3-D spring element. The structure can reduce critical pressure at which valve begins to open.

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A design approach of valve-less diffuser micropump driven by piezoelectric element (PZT) was developed. Its performance is higher than previous pump, because of following two reasons. Firstly, range of applied viscosity is wide. Secondly, a flow rate is controllable widely low to high. With the result that maximum viscosity of 23mPa・s and maximum flow rate of 700μL/min were achieved. These results have high potential for the pump development to dilute high viscosity sample.

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This paper proposes the method that a hexapod robot is traversed irregular terrain such as the stairs or slopes using the hierarchical decentralized system. A Upper subsystem, analizes the stability while walking and instructs lower subsystems, is made to participate in the decentralized system of which a lower subsystem one leg is controlled object. So the robot was achieved walking that adjusted to an environmental change in cooperated operation between subsystems. A conventional "Zero Moment Point(ZMP)" is a useful criterion of stability, but it does not evaluate the degree of stability. Therefore this paper proposes a "Acceleration Stability Margin" is amount of acceleration that ZMP is necessary for limit in stability area to move. Then Six-legged Walking Chair Robot, developed, achieved walking on irregular terrain that improved a movable ability while keeping the lowest stability margin by evaluating Acceleration Stability Margin at each environmental change.

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The purpose of this research is to develop a new type of cleaning robot based on a father-son architecture. One of the advantages of a father-son architecture is that the robot can enter narrow space while remaining powerful. This paper describes the system's architecture, a method for cooperated operation, as well as the design and assembling of such a robot.

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Recently, in our country, the population of aged people is increasing, but on the other hand, birth rate is decreasing. With this situation, the number of aged drivers has grown. Moreover, half the number of the handicapped people in our country has the restriction for travelling. As for these people's social infrastructures, cars play important role. However, this includes problems in traffic accidents and environmental surroundings, too. We propose an intellectual human vehicle in human centered city space, to solve these problems.

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Acquisition of actions based on prediction, which needs some context information, is important for a robot in dynamic environment. In this paper, task of avoiding moving object is employed first. The appropriate actions for this task are learned based on the combination of neural network and reinforcement learning. Architecture with Elman-type recurrent neural network and that without it are compared. Simulation result is shown the effectivity of recurrent neural network for this task. What is more, task of going to goal avoiding moving object is employed, and effect of learning system with Actor-Q architecture which could choose an action from plural that is verified for this task by simulation.

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In recent years, robot technology has remarkably developed and many researchers have worked on mobile robot behavior control. We suggest a sensor seiected fusion method based on neural network for a mobile robot navigation. In this method, we evaluate sensor values by possibility measure and select useful ones among all sensors according to selection rule with fuzzy logic. Back propagation algorithm is applied to neural network learning. In some cases, it's hard to determine the teach data for learning, therefore the data is acquired by GA. In addition, self-organizing map is used as a constraint condition in evolution. Through a simulation of mobile robot navigation, the effectiveness of the proposed method is clarified.

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From recent studies in machine learning, making a proper use of multiple simple controllers may show much better performance than using just one big controller. Thus, it is important for agents to obtain standards for separating assigned tasks into sub-tasks, which yet fully discussed. In this paper, we propose a method which enables to criticize the effectiveness of goals for each sub-task by agents themselves. Here, agents innovate criteria, a combined information available to agents through learning. Agents then decide a policy, which declares that one criterion has the highest influence over the result of sub-task learning. Through simulation and actual learning, agents attempt to match policies to candidates of sub-task goals. We have attempted experiment on sweeping task and verified how the proposed algorithm works comparing to conventional approaches.

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This research in concerned with image recognition on a robot vision using chaotic search. As a nonlinear dynamical system, BVP model is treated, which shows the behavior of neuron in biological system. This model has the edge of chaos, which exists on the boundary between a periodic solution and a chaos. This edge of chaos is an important area to maintain a flexible organization. In this research, the chaotic search is applied to image recognition utilizing the edge of chaos. First, the occurrence of chaos in BVP model is examined using the Lyapunov exponent. Second, in order to perform image recognition, a method of chaotic search is proposed and to distinguish whether it is a target, using a method of pattern matching. Finally, through simulation studies, it is verified that chaotic search is possible both for fixed and moving targets.

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This paper describes a new learning method of the humanoid robot. To make the humanoid robot acquire the concept of various objects, we did two big devices. One is use of the algorithm, which is self-organizing neural network, that can be studied online additionally. Another is to have given the desire to study to the humanoid robot, and combine it and the body to aim at the efficiency of study.

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In this paper, we propose Multi User Learning Agent(MULA) to interact with various types of people effectively towards realization of Social Interaction. MULA is equipped with two functions for social learning. One is direct learning function by individualization of user parameters, and another is indirect learning function by past experience and the similarity between each users. MULA adopts an extended classifier system which uses a classifier strength and a user profile for each people. Each person's classifier strength is enhanced by the interaction with the person and the past experience by similar type of people. We verified the effect of MULA by experimenting in interaction with six human beings using AIBO ERS-220A. It confirmed that this system promoted learning efficiently to two or more persons.

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A long-term experiment of robot assisted activity for elderly people has been conducted at a health service facility for the aged since Aug. 2003. Three therapeutic seal robots, Paro, were introduced there. This paper describes the results of the experiment. Face scales that consist of illustrations of person's faces were used to evaluate person's moods. In addition, Geriatric Depression Scales were used to measure person's depression by questionnaires. As the results, feelings of the elderly people were improved by interaction with the seal robots.

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The experiments on the human's burden were conducted to develop a self-transfer aid system. A person with weak leg muscle who uses a wheel chair is assumed to be a target user. By using a transfer aid system, a user can transfer between a wheel chair and a toilet. The basic experimental results using a self-transfer aid system were presented in this paper.

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This paper proposes imitation learning for a partner robot by using human cyclic gestures. The mobile robot used as a partner robot must make decisions suitable to the facing environment, imitative learning does not explicitly need an evaluation function specific to each behavior. Therefore, the robot can directly learn behaviors through interaction with a human. In this paper, we propose imitative learning based on spiking neural network, self-organizing map, and steady-state genetic algorithm. Furthermore, we show experimental results of the partner robot based on imitation.

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In this study the method which generates the working plan of a dual manipulator system for robotic sheet metal bending is proposed. In work planning for robotic sheet metal bending, grasping position and reposition timing must be determined and co-operative movement between left- and right-side manipulator is required in order to realize the efficient operation. In the proposed method, the best grasping positions and the reposition timings are determined based on the single manipulator operation and a smart co-operative motion is realized. Computer simulation is carried out based on the proposed method and illustrative examples and results of simulation are given. The effectiveness of this method is discussed.

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An intelligent wheelchair robot has been developed focusing on the inverse pendulum function. In this paper, an automatic guidance system using line trace control is explained to obtain the more intelligent wheelchair robot.

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The purpose of this study is to control simultaneously, motion and vibration of flexible 2-link robot arms. For this purpose, we had used modeling method called an 'extended reduced-order physical model (extended model)' to make a model of one-link flexible robot arm. The model of the flexible 2-link robot arms is made of a combination of the model of each link that is regarded as one link flexible robot arm. To connect each link, the constraint addition method is used. This is creating method of an equation of motion in multi-body systems. It is verified that the results of the simulation are effective for control of flexible 2-link robot arms.

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Recently, various types of miniature robots have been applied for real-world problems. In this paper, we develop a small mobile robot working under office automation floors. The size of the robot is 160×200×85[mm]. We use infrared sensors for self-localization and collision avoidance. The experimental result shows the robot can avoid collision with the obstacles.

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New magnetic and electric suspension systems are proposed in which suspension force is controlled by using a transformer with a variable coupling mechanism. The proposed suspension systems are equipped with a transformer whose primary coil is energized by an AC power supply. The secondary coil is connected to the coil of an electromagnet for suspension in the case of magnetic suspension and to electrodes for suspension in the case of electric suspension. The mechanism operates to change the coupling factor between the primary and secondary coils according to a command signal. Since the voltage induced in the secondary coil is a function of the coupling factor, the suspension force changes in relation to the command signal as a result. An experimental apparatus for single-axis magnetic suspension was fabricated. It was experimentally demonstrated that the suspension force can be adjusted with the developed variable coupling mechanism.

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In this paper we propose a mathematical model to describe the dynamic behavior of a feed drive system during microscopic motion. The mathematical model is constructed by combination Coulomb friction with nonlinear spring. Comparing the experiments to the simulations, it is found that the model can be represented by the only Coulomb friction term in the range: over 150μm, by the nonlinear spring only in the range: less than 50μm and by the mixed friction model in the range: 50〜150μm.

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As the modeling technique of a flexible arm, the modeling method by the distribution constant system and the concentration constant system can be considered. The virtual joint model in the concentration constant system can be modeled with a mass, a spring, and a damper the model can be made easily. In this research, a flexible arm is considered to be the rigid body arm of 2 links using a virtual joint, and it aims at performing vibration and force control. And the validity of the proposed method is checked by the simulation and experiment.

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In this paper, We proposed a method of the attitude control of six-legged robot in consideration of time-delay of hydraulic actuator by optimal servo control system. The model, which the inputs are the control input of the thigh link and the outputs are the height of the body, pitch and roll angles, is made. In the case of using hydraulic actuator of the third order delay system, the proposed model becomes uncontrolable. So, the third order delay system is approximated by the second order delay system. This system is controlled by optimal servo system. The validity of the proposed method is verified by comparing with the case not considering the time delay of hydraulic actuator.

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This paper describes a moving characteristics of in-pipe mobile microrobot driven by pneumatic pressure and elastic force of a spring. This robot consists of a bellows actuator and friction rings of robot's foot. The bellows actuator is structured by rubber bellows and spring which is inserted in the bellows. The pneumatic pressure is used to stretch and the spring is used to shrink an actuator of the microrobot. The friction ring converts the stretch motion and shrink motion into the advancement drive. We confirmed to move in 26mm inner diameter pipe and characteristics of relationship between moving speed and distance of air feeding tube.

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Recently micro manipulation and nano manipulation techniques have drawn a lot of attentions because of their potential utilities not only in manufacturing fields but alsoin medical and bioengineering domains. There are many prior systems which were developed to accommodate an accurate positioning capability. However, changing the orientation of a manipulation probe is considered far more difficult in such systems than changing the translational position alone. Facilitating a posture changing mechanism, in general, leads to a large scale apparatus or highly expensive system. This research is intended to provide a posture changing ability for micro manipulation at reasonable cost by usingan offset planar hinge mechanism. The current report presents a prototype system which has recently been developed.

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There have been increasing demands on micro/nano manipulation techniques because of their potential contributions to medical and bioengineering fields. Applicability of a micro manipulation system can be further extended if the system allows a user at a remote site to operate on the system via Internet. However, a time delay between two sites sometimes becomes intolerably long such that a stable operation cannot be maintained. This report investigates how the communication delay affects the remote opetation on micro manipulation tasks through several experiments.

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The Strand-muscle actuator has been developed imitating mammals' muscles. A compact multi-D.O.F. flexible joint is easily realized using the actuators. Several hexapod walking robots, robot hands and a shoulder have already been manufactured. In this research, a miniature hexapod robot. SRAMI-1. has been developed. The robot is remote controlled, energy independent, and can adapt to rough terrain with flexible joints. It is expected the robot will contribute to search/rescue activities at narrow rubbly places in disaster area. In this article the mechanism and control system of SRAMI-1 are introduced.

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Ultrasonic thickness measurement at a rough corroded surface results in a large measuring error indicating over thickness estimation. In order to reduce the measuement error, we conducted thickness measuring experiments of corroded steel plates using soft element probes whose contact surface can change their shape to fit the rough surface. We also conducted experiments with a conventional probe for comparison. The result shows that the soft element probes(element diameter: 5mm) are effective for error reduction, but errors by the soft element probe (element diameter: 10mm) is nearly the same as conventional one.

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A new position surveying machine is fabricated. Position surveying is done by using of two rotary encoder sensors. The camera is carried in the head of a position surveying machine and the inspection and the survey in a pipe can be performed simultaneously. In this research, the inclination sensor is carried and a result is rectified when the machine inclines. The position surveying robot can measure the position at the error less than 18.22mm in a straight and curved plastic pipe which has radius of 106m at its center and is 20m long and 44mm thick in diameter.

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The object of this study is to investigate an on-board diagnostic method to detect the deterioration of a three-way catalyst under actual driving conditions. For this purpose, we analyzed the signal data, which consists of air-fuel ratio and NOx concentration, generated by two ZrO2 NOx sensors placed on upstream and downstream positions of the catalytic converter. As a result, we found that it is possible to detect deteriorated catalyst under actual driving conditions by using effectively airfuel ratio signals and NOx concentration signals of two NOx sensors placed on upstream and downstream positions of the catalytic converter.

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Adsorption chiller that can drive with waste heat at low temperature is very important to use energy effectively. To obtain the performance of the refrigerant with the temperature of 0℃ or less, the selection of the refrigerant and the adsorbent is important. Water, methanol and mixture of them arc used as a refrigerant, and activated carbon, silica gel and mixture of them are used as an adsorbent. The influence of these mixture contents on equilibrium adsorption and adsorption rate were measured. It is clarified that the equilibrium adsorption increases as the methanol ratio and the mass fraction of activated carbon increase. Furthermore, the effect of activated carbon mass fraction on the adsorption rate was examined. The rate with the mass fraction of 50% is larger than that of 0%.

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Two-phase flow boiling heat transfer of water in a horizontal small diameter tube, ID=0.9mm, was experimentally examined at a atmospheric pressure condition in a range of mass flux from 84 to 255kg/m^2s. The correlation developed for a 1.45mm ID tube was applied to predict pressure drop and local heat transfer coefficient. Predicted pressure drop was within an error of 20%, at a higher heat flux, however, the error increased to be up to 40%. The effect of mass flux and location on the heat transfer coefficient was small. The heat transfer correlation well predicted at a range of Re_G<2000, but it gave worse predictions at Re_G>2000.

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Microbubbles are very small bubbles with diameters of 50μm or less. The important characteristics of microbubbles are their large specific area and small buoyancy and therefore effective dissolution of gas phase and adsorption rate are expected. The utilization of microbubble is useful to improve water environment. Research efforts at a number of institutions have been devoted to development of microbubble generator. However, complex mechanism and high power supply are required for previous microbubble generation devices. In this study, three types of model (slit angle θ=30, 60, 90 deg) were installed in order to develop the compact and low power microbubble generator and microbubbles were generated by pipe with slits. For θ=60 deg, the microbubble generator showed the superior performance in comparison with the other models. It was confirmed that the microbubble generation was affected by the slit angle.

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