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A carbon nanotube (CNT)-based devise has advantageous features of high absorption ratio in broadband terahertz (THz) frequency region and mechanical bendability. We here report on CNT THz imager, which enables the THz wave detection under mechanical stretching. The developed techniques are highly expected to contribute to non-stressful and wearable applications for bio-monitoring.

Because of unique plasmonic features, nanostructured graphene such as graphene nanoribbons (GNRs) and quantum dots (GQDs) is attracting much interests. In this work, we investigated real-space characterization of surface plasmon polariton (SPP) in GQDs on SiC substrate by utilizing a scattering-type scanning near-field optical microscope (s-SNOM) in the mid-infrared (MIR) band. Nanoscale near-field images revealed that the SPP in the GQDs was excited at the wavenumber of 929.02 cm−1, where the SPP in two-dimensional (2D) graphene has not been reported. The present findings provide not only a deeper understanding of the SPP in graphene nanostructures, but also a first step for exploring new plasmonic functionalities impossible with conventional 2D graphene.

This paper presents results on nMOSFETs with the La-doped high-k/metal gate stack to see its suitability for sub-32nm LSTP and HP applications. The 32nm gate length transistors exhibit an excellent I on -I off characteristic, and the PBTI results meet the 32nm technology node requirement. Furthermore, for the first time, V t variation in the La-doped high-k/metal gate stack devices is investigated. The results suggest that employing the metal electrode suppresses V t variability while no additional parameter fluctuations due to La-doping of the high-k dielectric were observed.

Stackable ROADMs (S-ROADMs) have been proposed for use in regional IP-over-CWDM networks. The S-ROADM can be constructed by connecting modules with different wavelengths required in the node. The experimental results clarified that the S-ROADM could mux and demux the wavelengths successfully, and gave no limit to the passing-through wavelengths, making the network be wavelength transparent. Contrary to the S-ROADM, the existing fixed ROADMs were not wavelength transparent. The bidirectional S-ROADMs have also been proposed, and lightpaths could be reconfigured successfully in an IP-over-CWDM network with the bidirectional S-ROADMs.

This paper proposes a novel DC-AC converter topology for fuel cells applications, and mentions the reduction methods of input current-ripple. Fuel cells are generated electricity by chemical reaction. Chemical reaction time is much slower than commercial frequency. So, input current-ripple may damage the fuel consumption and life span. The conventional DC-AC converter for fuel cells has large capacitor between boost converter stage and PWM inverter stage, in order to reduce the input current-ripple. That capacitor prevent from reducing the size of its unit. The proposed DC-AC converter, called pulse-link DCAC converter provides boosted-voltage pulse directly to PWM inverter. This topology is no need to insert large capacitor. Furthermore, the series LC circuit which is inserted on proposed topology works as ripple canceling. This paper shows the mechanism of current-ripple reduction. Moreover, active input current-ripple reduction method is shown.

This paper develops a 3-DOF active rotational ball joint with a simple and compact mechanism, which can realize a rotation around an any- direction rotational axis with a well manipulability and can change its direction of rotational axis smoothly and arbitrarily when it is on rotating. The mechanism principle of this joint is proposed and analyzed. Then the ball joint is developed and experimental verification on the proposed mechanism is performed. The effectiveness of the mechanism principle is outlined by some experimental results.

We synthesized new multi-components spinel ferrite including Ni, Mn, Zn, Co, and Fe in order to improve the magnetic properties in nanosized particles by using a chemical coprecipitation method. The samples were synthesized in the mole ratios of MxMyFe(1_x+y)OldrFe2O3 (Mx My=Ni, Mn, Zn, Co, 0

This paper proposes a novel DC-AC converter topology for fuel cells. The proposed circuit topology has no need smoothing circuit because boosted voltage from first step provides directly to PWM inverter. The notice point is that the output voltage from isolating step (third step) is pulsed waveform, and pulse voltage is also made from DC at the converting step. As the result, the smoothing step will be able to be cut if the demanded voltage in one switching period provides to converting AC step within pulse voltage is output. Furthermore, this topology is expected to achieve ZVS of the PWM switches because pulsed voltage has certainly zero voltage periods in the switching period. As the results, it will be possible to reduce the size of this component. Moreover, input current-ripple is damaged to the life span of fuel cells. Using the topology, the method of input current-ripple reduction is shown. This paper shows the advantage the converter by the experimental results.

In this study, a field-emission cathode ray tube (FE-CRT) has been fabricated using novel kind of electron emitter called carbon nano-exit (CNX) which has been developed on nickel, silicon and SUS substrate with a special plasma chemical vapor deposition (CVD) technique. Scanning electron microscopy(SEM) image indicates that the emitters have an array density of 2times108/cm2.

Advanced communication technologies enable sophisticated safety-enhancing systems that exploit numerous computing devices embedded in our commuting environments. However, the complexity inherent in these systems, together with the contingency in their real-life use context, can create usability problems that undermine safety. In this paper, we discuss an integrated, user-centered approach to designing and evaluating RFID-enhanced commuting environments for schoolchildren. Our integrative context sensing and sensemaking infrastructure exploits embedded computing devices not only for enhancing safety but also for understanding user experiences and thereby facilitating iterative usability improvement.

Zero-current transition (ZCT) converters for wind power generation systems are proposed. In order to reduce switching losses and noises, a soft-switching technique is adopted. It is suitable for the pulse-width modulation (PWM), because the resonant transition is very short duration and it is independent of the switching frequency. A laboratory prototype using a digital controller for the ZCT converter is assembled. From the PSPICE simulation and experimental results, the zero-current transition operation of the main switch is confirmed and the efficiency of the converter is improved. The proposed converters are suitable for independent small scale power network system using lower power wind turbines

Highly sensitive control of anisotropic optical polarization in CdMnTe quantum wires has been studied theoretically using multi-band effective mass method. A magnetic field dramatically changes the transition probability via the sp-d exchange interaction.

In this gaper we propose to use fuzzy sets to the rate control in a multisensor rate adaptive cardiac pacemaker system. The logic was applied to the rate determination tased on minute ventilation and oxygen saturation during walking.

A porous SiOCH film with k=2.3 is developed by a new concept PECVD, in which pore-involved molecules are piled up together to deposit a "molecular-pore stacked, SiOCH (MPS)" film. The pore size and the density of the film are controlled by designing the pore size and the steric-hindrance side-chains of the source molecules. A newly synthesized, 6-member ring-type, organo-siloxane with the side-chains of large steric-hindrance hydrocarbons realizes the MPS film with k=2.3. the basic feasibility of the MPS film is confirmed through the integration into Cu damascene interconnects. The MPS film is a strong candidate for the low-k, inter-metal-dielectrics in 45nm node, ASICs.

Rewriting systems are popular in end-user programming because complex behavior can be described with few or no abstractions or variables. However, rewriting systems have been limited to manipulating non-rotatable objects on a grid, such as in Agentsheets or Stagecast Creator. Systems that allow free-form movement of objects must use other techniques, such as the sequential programming by demonstration in Squeak. Viscuit is a new rewriting system that introduces fuzzy rewriting, which allows freely positioned and rotated objects to interact using only rewriting rules. The result is a system that allows users to specify animations in a highly interactive way, without textual language or menu selections.

Interpreting general purpose programming constructs can be difficult because it requires context, such as knowledge of language syntax or idioms, which users may not have readily available. In such cases other source of context may complement or substitute. This paper proposes annotating program comments with hyperlinks that the user can select to restore the complete runtime state of the program, a technique we call snapshot documentation. The generality of snapshot documentation across user skill and system complexity suggests that it may be useful for gentle-slope systems, i.e. systems that are designed to allow users to acquire a full range of programming skills in an incremental yet continually useful way.

The paper introduces the application of IEEE 802.11e to the delivery of high bandwidth multimedia streams. The architecture for a QoS enabled MAC is described along with an efficient scheduling algorithm, which, when deployed at the AP, is able to serve QoS sensitive streams, while making efficient use of the channel bandwidth. The 802.11e MAC is simulated using OPNET and the performance of both the EDCA (enhanced distributed channel access) and the HCCA (HCF controlled channel access) mechanisms is studied under various scenarios. The results illustrate that HCCA when used in conjunction with the QoS scheduler satisfies the requirements of AV and speech applications.

Reliably of Cu damascene interconnects (DDIs) using United Hard-mask and Cap (UHC) structure, which involves the same material for both Hard-mask and Cap layers is investigated. Line-to-line insulating reliabilities such as a leakage current, TZDB and TDDB are greatly improved by using the UHC structure even without any barrier metal layers, indicating that the interline leakage path is not in a bulk of the low-k dielectric but the interface between the Cap and the CMP-damaged Hard-mask. This new Cu dual damascene interconnect with UHC provides the interconnect reliability of future ULSIs with ultra-thin barrier metals toward a barrier-metal-free structure.

A highly reliable, 65 nm-node Cu interconnect technology has been developed with 180 nm/200 nm-pitched lines connected through /spl phi/100 nm-vias. A porous SiOCH film (k=2.5) with sub-nanometer pores is introduced for the inter-metal dielectrics (IMD) on a non-porous, rigid SiOCH film (k=2.9) for the via-infra-line dielectrics (via-ILD). A key breakthrough is a special pore-seal technique, in which the trench-etched surface of the porous SiOCH is covered with an ultra-thin, low-k organic silica film (k=2.7), thus improving the line-to-line TDDB (time dependent dielectric breakdown) reliability of the narrow-pitched Cu lines. The fully-scaled-down, 65 nm-node Cu interconnects with the porous-on-rigid SiOCH hybrid structure achieve excellent performance and reliability.

The highly reliable low-k/Cu dual damascene interconnects (DDI) with in-situ fluorinated carbon-nitride (FCN) barrier was successfully obtained in an organosiloxane film. Using C/sub x/F/sub y/N/sub 2/-base plasma, the DDI etching is achieved by sidewall-deposited fluorocarbon polymers. In addition, the etched-surface is covered with the FCN barrier, which suppresses the Cu diffusion.

Hybrid-type, Cu dual damascene interconnects (DDI) are fabricated in a porous organosilica film (k = 2.1) inserted between low-k films of hard-mask (HM) and etch-stop (ES) layers. Plasma-polymerized, divinyl siloxane bis-benzocyclobutene (p-BCB, k = 2.7) film, instead of SiCN film (k > 4), is selected for these HM and ES layers due to the low k-value as well as the high etch-stop property to the porous film. The line capacitance in the hybrid-type, Cu-DDI with BCB-HM and BCB-ES layers decreases 20% compared with that of the Cu-DDI with SiO/sub 2/-HM and SiCN-ES layers, achieving the effective dielectric constant (k/sub eff/) of 2.6. This new interconnect structure is a strong candidate for the 70 nm-node ULSIs.

This paper presents the characteristics of a MCCT (MOS controlled cascode thyristor) device with a blocking capability of 600 V for the first time. It should be noted that a superior on-state voltage drop of 2.0 V can be achieved while exhibiting a fast turn-off speed which is comparable to that of an IGBT. Furthermore, the MCCT shows a superior short circuit withstand capability of more than 16 /spl mu/s and a maximum turn-off capability of over 660 A/cm2 at a high temperature condition of 125/spl deg/C, simultaneously, by the application of an n/n/sup +/ source region structure.

This paper proposes a method to automatically detect service interference with a rule-based system and an extended adjacency matrix. The proposed method uses and combines features of both the adjacency matrix and rule-based system. The method first generates the extended adjacency matrix by the rule application, then extracts sequences of the state, the event, and the rule applications, and then detects the service interference with the extracted sequences.

We propose a buried metal heterojunction bipolar transistor (BM-HBT), in which buried metal in the collector layer could reduce the total base-collector capacitance. To show the possibility of making a BM-HBT, we fabricated an InP-based HBT with buried tungsten mesh replacing the subcollector layer, where tungsten mesh works as a Schottky collector electrode. A flat heterostructure on the InP collector layer of the buried tungsten mesh was confirmed by a cross-sectional SEM view. A DC current gain of 12 was measured from the common-emitter collector I-V characteristics.

This research is aimed at investigating the use of kinetic typography in order to appreciate a work in the Internet art museum. Kinetic typography is the animation of the character expressed by computer. Being accompanied by various motions, kinetic typography can add messages, such as feeling and directions, to the meaning which language involves. The Internet art museum is expressed by virtual space, which has two or three dimensions, expressed by computer. The exhibit works in the Internet art museum could be linked to various information, without being restricted to space or time. Kinetic typography may help to grasp the relation of ambiguous information clearly in such case. Through the experiment, the attributes of kinetic typography have been indicated as ornamentation of motion, settlement of motion, motion classification, and timebase appearance. A motion is an expression of some meanings and includes additional information. When a motion of kinetic typography is applied to the intention of a message, the motion can express a meaning effectively.

The authors propose a visual design support system for telecommunication services that uses the state transition rule (STR) as specification knowledge and a description language. The system has excellent design support facilities, which are discussed. A designer, who has no knowledge of the professional aspects of network specifications, can describe various services from the user's viewpoint using the STR-GR (graphical representation) description method. Merely by synthesizing some service descriptions, the system can automatically validate the service interactions by means of rule conflict detection. A designer can verify a service specification by simulating a designed service description and displaying its execution processes in an animated form. The experimental evaluation of the design support system is presented. >

In order to develop an ultra-compact and super low-noise MMIC amplifier for the receiving system of PHS, the input and output impedance of an ion-implanted planar GaAs MESFET were successfully reduced while maintaining its high-gain and low-noise characteristics. The MMIC had a noise figure of 1 dB and a gain of 13.5 dB at 3 V, 20 mA and 1.9 GHz in an ultra-compact plastic package. The fabricated switch and LNA module employing this MMIC has achieved the low-noise property of less than 3 dB.

2nd generation dual gate MOS thyristor (2nd gen.-DGMOS) with 900 V blocking capability are presented to realize an extremely excellent trade-off characteristic between an on-state voltage drop and a turn-off loss with a high turn-off capability and to overcome the IGBT's characteristics for the first time. A superior on-state voltage drop (Von) of 1.29 V at 10 A(71.3 A/cm/sup 2/) with the turn-off loss (Eoff) of 101 /spl mu/J is successfully achieved. These values of Von, Eoff indicate the much superior trade-off characteristic to the IGBT. Furthermore, it should be noted that the 2nd gen.-DGMOS achieves better turn-off capability of approximately 500 A/cm/sup 2/ in a voltage resonant circuit, which is 3.0 times higher than that of the conventional DGMOS.

We have developed an ultra-compact dual-use (antenna/local) switch IC for PHS operating at +3/0 V. This IC has a circuit configuration which utilizes MESFETs with two kinds of pinch-off voltages. Additional applied techniques include a circuit design method that employed electromagnetic field analysis, a pull-up method which utilizes forward current flowing in order through the gates of MESFETs, and high isolation characteristic obtained by use of a chip inductor. The insertion loss and isolation characteristics of this IC are, respectively, 0.54 dB and 28.4 dB at 1.9 GHz and 0.48 dB and 30.0 dB at 1.65 GHz. Furthermore, we were able to suppress adjacent channel leakage power to 61.5 dBc at 600 kHz offset during input power of 22 dBm QPSK modulated signals.

This paper discusses architectural aspects of personal communications services (PCS) for an early introduction of services in isolated areas. The advanced intelligent network (AIN) and front-end processing architecture are studied. However, PCS for small areas should provide not only connection oriented existing telephone services, but also transaction-type data services, multimedia services and advanced services (e.g., ones with a smart card) in order to be timely. Also, it should be compatible with the current intelligent network (IN) or AIN architecture for implementing universal personal telecommunication (UPT) numbers, or seamless services between local dedicated services and nationwide universal services. This paper describes how a better understanding of this new architecture will result in improved IN services that may be offered to local PCS users along with dedicated services. >

Concatenated trellis coded 8PSK with Reed Solomon (RS) codes is studied over additive white Gaussian noise (AWGN) and Rayleigh fading channels. By using an erasure and error decoding scheme for a Reed Solomon decoder, one can get an improvement of bit error rate performances for the concatenated coding system. In order to realize this erasure and error decoding of RS codes, it is necessary to extract the reliability information with respect to the input symbols to the RS decoder. The reliability for an RS code is based on erasure declaration which can be obtained by an inner code decoder of a concatenated code. A new modified Viterbi decoder with averaged reliability information is proposed which is very suitable for a practical use with a truncated observed length. The bit error rate performance is calculated by computer simulation over AWGN and Rayleigh fading channel. >

The authors developed a high energy density sealed Ni-Cd battery consisting of a pasted nickel electrode with a highly porous Ni fiber felt substrate and high-density nickel hydroxide powder. The high-density nickel hydroxide powder having a spherical shape made it possible to obtain a pasted nickel electrode with an energy density exceeding 550 mAh/cm/sup 3/. The nickel electrode with high density nickel hydroxide powder added with Zn or Cd as a solid solution improved the cycle life and high-rate discharge characteristics. Additionally, high temperature charge acceptance is improved by the addition of cobalt together with Zn or Cd. The newly developed battery has a capacity of 800 mAh in AA size. 1800 mAh in SC size and 3000 mAh in C size. >

We have developed a 20 Msample/s 10 b CMOS ADC with a 2.4 V power supply, in 0.35 /spl mu/m 1-poly 2-Metal ASIC process without a special analog process, which is suitable for embedding in ASICs because of the small area (4.84 mm/sup 2/) and small power consumption. To realize this ADC we have developed a 2-step interstage amplifying pipeline system and new circuit technologies for residue amplifiers. The prototype chip was fabricated and was measured. It shows good linearity of less than /spl plusmn/1 LSB and 28 mW power consumption with 2.4 V at 20 MHz sampling.

A method was proposed for discrimination of ventricular arrhythmias using fuzzy logic. The classifier uses four features of ECG waveforms; amplitude variation ratio, interval variation ratio, peak sharpness, QRS complex width, and assigns each waveform a number of 0-100. The performance of the algorithm was evaluated on the surface and intracardiac electrocardiograms of ventricular tachycardia (VT), ventricular fibrillation (VF) and normal sinus rhythm (NSR) in mongrel dogs. NSRs were evaluated 90-100 while VFs less than 10. VTs were assigned the numbers of 30-75. An automatic detection and defibrillation experiment was performed with this algorithm.

The paper proposes a reactive method that supports the design of service specifications or service scenarios based on a state transition model. A state transition consists of a current state, an event (including tasks) and a next state, and is usually treated as a unit of information. For cooperative actions to be achieved when several services are combined, it is necessary for the sub-elements of each state transition to cooperate. With conventional methods, unfortunately, this is difficult. The method proposed, consists of the following techniques: (1) three decompositions of a state transition; (2) a formal description; (3) the application of reactive rules; and (4) the use of the conflict and cooperation strategy knowledge. With the proposed method, specifications or actions for cooperation can be achieved. To show the effectiveness of the proposed method in an easy to understand manner, examples of telecommunication services are provided. Cooperative resolution in the interactions among several services is also shown. The proposed method supports not only the design of cooperative specifications but also the rapid and efficient development of software.

High power semiconductor devices are required for various applications like a motor control in traction system. Desired device characteristics for such applications are low forward voltage drop, high current capability and large blocking voltage capability. Insulated Gate Bipolar Transistor (IGBT) is now widely accepted for many applications due to its simple gate control and current saturation feature, and many studies have been done for its high voltage application. It has been found that this device structure has a high forward voltage drop at a large current density when designed for the high voltage application. As an alternative, MOS-gated thyristor structures such as MOS Controlled Thyristor (MCT) and Base Resistance controlled Thyristor(BRT) have been studied for the high voltage application because of its simple gate drive capability and low forward voltage drop. However, since this device does not have the current saturation feature, passive protection must be provided for its stable operation. In this paper, a new class of MOS-gated thyristor structure named MOS Controlled Cascode Thyristor (MCCT) which exhibits a superior short circuit withstand capability as well as the low forward voltage drop will be demonstrated for the first time. Furthermore, this device shows a fast switching speed which is comparable to that of an IGBT and an excellent maximum turn-off capability, simultaneously.

In this paper we propose the fuzzy artificial intelligent system (FAIS) with learning function. This system has some functions which acquire new fuzzy knowledge from experiences under an unknown situation, and can solve some problems by deducing new state through fuzzy reasoning. Also, the purpose of constructing this system "FAIS" is to make a system that can solve many kinds of problems in various fields. As an example, our system "FAIS" is applied to a medical diagnosis and treatment advice system, and the usefulness of this system is discussed from simulation results. >

A high-isolation switch IC with 31 dB isolation and 0.88 dB insertion loss at 1.65 GHz, sealed in a 6-pin ultra-compact plastic package having approximately 1/4 the conventional area, was developed for the first time. An electromagnetic-field simulation analysis of the isolation characteristics between the lead pins of the ultra-compact package was used for this IC together with a new design method which takes into account deterioration of the isolation characteristics due to the plastic molding. Electromagnetic-field simulation was also used in the layout design to minimize chip size.

Ultrasonic complex vibration welding systems of 100 to 200 kHz using a complex vibration welding tip with large area vibrating in elliptical to circular locus were studied. The complex vibration systems have a welding tip part of 21 mm/spl times/21 mm area which is available for direct welding of semiconductor tips of 20 mm square on substrate (face down bonding) and packaging of various electronic devices.

We fabricated GaInAs/InP based buried metal heterojunction bipolar transistors (BM-HBTs), in which a tungsten stripe with the same area as the emitter was buried with an intrinsic collector layer. In this device, there was no conductive layer under the extrinsic base region to reduce the total base-collector capacitance (C/sub BCT/). Though tungsten was embedded in an active region of HBTs, flat surface of base layer and no void formation around buried tungsten were confirmed by the observation of cross section. C/sub BCT/ of 10.3 fF was calculated from Y/sub 12/ parameters and an effective base-collector junction area of BM-HBT was estimated at 22% of conventional-HBT.

A HDTV video processor with decoding/display of two MPEG MP@HL streams and reverse playback with smooth 30 frames/s without frame skip uses a 0.18 /spl mu/m 5-layer process in 6.86/spl times/6.86 mm/sup 2/ and 5.7M transistors. It is for home multimedia and mobile TV applications. It operates at 135 MHz and 0.8 W at 1.8 V.

Using a low-k porous organosilisesqueoxane film, ALCAP/sup TM/-S with k=2.1, dual hard mask (DHM) process is proposed for Cu dual damascene interconnect (DDI) formation. The porous organosilica film has very high etching rate relative to those of the hard mask (HM) and/or etch-stop materials. SiO/sub 2//SiC is one of the best combinations for the DHM, in which the lower hard mask of SiC remained after metal CMP and protects the porous film from the via-etching damage in misalignnent region between the via-hole and the buried Cu-line. Applying in-situ resist-ashing with N/sub 2//H/sub 2/ gas, 0.4 /spl mu/m-pitched dual damascene structure is successfully fabricated. Increment of the dielectric constant is suppressed within 5% (k=2.2) after the Cu-interconnect fabrication, confirming that the DHM low-damage process is applicable for the Cu DDI fabrication in ultra low-k, porous organosilica systems.

The effect of underlayer texture on Cu film properties and electromigration performance in Cu damascene interconnects have been studied. The Cu film orientation depends strongly on the underlayer texture. The Cu orientation can be controlled by changing the preferred orientation of the TiN underlayer, which has the same cubic structure as the Cu. The Cu film deposited on a highly -oriented TiN underlayer indicates a strong orientation. The atomic arrangement between Cu(111) and TiN(111) planes has a rotational angle within /spl plusmn/10/spl deg/ around the axis in spite of lattice mismatch of 14.7%. In the case of damascene interconnects, sidewalls in a trench affect Cu texture and the dependence of the underlayer texture on the Cu film orientation becomes small as line width decreases. EM performance, however, has been improved by the realization of Cu damascene interconnects with a strong orientation.

A 200-gate ECL master slice LSI suitable for computer mainframe logic will be described. Optimization has resulted in a 1.5-ns loaded delay.2.5-W power dissipation and compatibility with standard ECL components.