bluuebunny/crossref_metadata_2025_split huggingface dataset:
Finite‐volume/time‐domain analysis of electromagnetic wave propagation in two‐dimensional tunnels with fundamental junctions
Authors: Uchida Kazunori , Matsunaga Toshiaki , Han Kyung‐Koo , Kim Ki‐Chai 
Published: July 2007

AbstractThe problem of electromagnetic wave propagation in tunnels with branches and bends, such as those that would be found in an underground shopping center, has been analyzed with the finite‐volume/time‐domain (FV‐TD) method. The FVTD method is based on difference equations discretized by a volume integration of Maxwell's equations for arbitrarily small polygonal cells. In this method, the medium constants within the infinitesimal cell are constant and their values differ from cell to cell. Therefore, this method can easily handle the boundary value problem with an arbitrary shape that contains inhomogeneous media. In homogeneous media, the FVTD method and the finite‐difference/time‐domain (FDTD) method are equivalent in the Descartes coordinate system. In one application of the FVTD method, numerical calculations were made for tunnel structures that are typically difficult to analyze. To prove the usefulness of the FVTD method, a microwave simulation experiment was done. The numerical and experimental values were shown to agree well.
Analysis of diffracted waves from isotropic chiral gratings
Authors: Matsumoto Keiji , Rokushima Katsu , Yamakita Jiro 
Published: July 2007

AbstractThis paper proposes an analysis method of diffracted waves in isotropic chiral gratings with periodicity in an arbitrary three‐dimensional direction. In this method, the spatial harmonic expansion method applied to the analysis of anisotropic dielectric gratings is extended. By Fourier transform of the periodicity of the chiral admittance, a systematic matrix form is used for rigorous formulation. In the numerical examples given here, calculations are carried out for the density modulated grating in which the relative dielectric constant and the chiral admittance distributions are varied sinusoidally. A coupling between the circularly polarized diffracted waves due to the Bragg condition and an anomalous diffraction phenomenon due to the chiralty of the medium are presented. This coupling is not observed in the case of nonchiral isotropic dielectric gratings.
Measurement of refractive index distribution of optical waveguides by the propagation mode near‐field method employing an improved inverse analysis
Authors: Yabu Tetsuro , Sawa Shinnosuke , Geshiro Masahiro 
Published: July 2007

AbstractA method to estimate the refractive index profile of an optical waveguide exists in which the optical intensity distribution of the only one propagation mode is used. Since this method requires only a microscope and a television camera, setup is extremely simple and inexpensive, thereby making the method practical. The differential processing method and the inverse analysis method have been proposed as methods to use the optical intensity distribution of only one propagation mode. The mechanisms of these methods that use the optical intensity distribution are presented in detail here. As a consequence, a new method that overcomes the difficulties in the previous methods, to be called Improved Inverse Analysis Method with Fewer Parameters, is proposed. Further, by using this proposed method, the index profiles of the step‐index type optical fiber and the buried optical waveguide can be estimated in order for validity of the method to be studied.
Unified solutions of the scattering coefficients of E‐plane junctions in rectangular waveguides
Authors: Widarta Anton , Kuwano Shuzo , Kokubun Kinchi 
Published: July 2007

AbstractIn this paper, the scattering coefficients of the E‐plane right‐angle bend, T junction, and cross junction in a rectangular waveguide are derived by the mode‐matching method [12]. In this method, the electromagnetic fields in the junction section formed by a sectoral or a circular region are matched to those in the waveguide region. Since the T junction and the cross junction can be constructed with several right‐angle bends, their scattering coefficient solutions can be unified in the same form as those of the right‐angle bend. The expressions for these solutions are simple, convenient, and the numerical values are highly accurate over a wide frequency range. By using these values, the details of the scattering characteristics of the dominant and higher‐order modes at the junction can be obtained. The resonance phenomena of the dominant and the higher‐order modes in the high‐frequency range are important for the study of the fundamental characteristics of the microwave circuits.
Measuring system for diffusion length of photoactive compound in post‐exposure bake process
Authors: Sekiguchi Atsushi , Sensu Yoshihisa , Matsuzawa Toshiharu , Minami Youichi 
Published: July 2007

AbstractThe post‐exposure bake (PEB) characteristics of a photoresist can be examined with a method that estimates the diffusion length of a photoactive compound (PAC) in the photoresist PEB process. Diffusion lengths are estimated with development rate measurement equipment using PEB conditions at temperatures of 50°C, 100°C, 110°C, and 120°. An ultrahigh‐resolution i‐line photoresist THMR‐iP3000 is used in the research. The obtained values are input into a photolithography simulator PROLITH/2 to calculate photoresist profiles. Using a 365‐nm wavelength, 0.5 NA, and 0.6‐coherence factor conditions, resist profiles for a 0.4‐μm line space feature are calculated with varied focus. The simulated results are compared with SEM observations to evaluate the validity of the estimation method; they are found to be substantially consistent with experimental results, thus confirming the validity of the method.
Characteristics and growth processes of a surface oxidized layer formed on Al‐Y alloy films
Authors: Takeyama Mayumi , Noya Atsushi , Murakami Yoshitaka , Sasaki Katsutaka 
Published: July 2007

AbstractThe formation process as well as the characteristics of a surface oxidized layer formed on Al‐Y alloy films are examined. Al in the alloy forms a thin Al2O3 layer due to more oxidation at the alloy surface. In an alloy of Al‐rich composition, if the Al2O3 surface layer (which is comparable to that formed on pure Al) is formed, the layer maintains its ability to be a self‐passivating oxide layer. In those alloys that form an unduly thin Al2O3 surface layer, introduction of oxygen from the ambient environment cannot be curtailed. As a result, oxidation proceeds and the formation of Y2O3 and reduced Al is observed within the oxide layer. In the oxidized layer, the oxidation state of the lesser amount of oxide is affected by that of the greater amount oxide; this reflects a shift in binding energy of the XPS spectra for the minor element. It is shown that the formation process of the alloy is dominated by the differences of ionization potential, an element affinity, formation heat, a diffusing species and the transport behavior of cations and/or anions.
Equalization of the coupling loss of LD array modules for an optical frequency multiplexed communications system
Authors: Kaneko Shinichi , Adachi Akihiro , Yamashita Junichiro 
Published: July 2007

AbstractThis paper proposes a method of equalizing the coupling loss among different channels of liquid display (LD) arrays. In this method, a second lens is used to adjust the image points to the fiber positions, which then are aligned and the coupling losses among channels are equalized. In addition, the compensation for misalignments is achieved by changing the position of the second lens. This is made possible by the dependency of the angle of the output light ray on the object height. As a result, the requirements with respect to the distortions of the optical system are relaxed by half and the module‐yield with coupling loss fluctuations in the range of ±0.5 dB is improved by about three times.
Tracing of the Poynting flux in a Stratified Absorbing Medium: The Geometrical Optics Field
Authors: Tokumaru Shinobu 
Published: July 2007

AbstractThis paper presents a method for tracing the flux line and Poynting flux amplitude in a geometrical optics field in relation to the circularly polarized absolute value ray when a plane wave is incident on a planar nondis‐persive layered lossy medium. For projected flux flow lines that are the projection of the Poynting flux flow lines onto the wavefront normal plane, it is shown that Format's principle holds for the projection flux flow lines if an anisotropic index of refraction of the projected flow lines related to the excitation method of the plane wave and dependent on the amplitude is introduced.
Analysis of nonreciprocal mode‐conversion properties of magnetooptic channel waveguides using the finite element method
Authors: Zhuang Xiu‐Ping , Koshiba Masanori , Tsuji Yasuhide 
Published: July 2007

AbstractTo evaluate nonreciprocal mode conversion characteristics in a magnetooptic channel waveguide, a finite dement analysis based on the scalar wave approximation is formulated for the first time. A simple iterative calculation method is conceived for solution of the nonlinear eigenvalue equations finally obtained in which the two polarizations are coupled. Specifically, the maximum isolation ratio in the mode‐conversion‐type magnetooptic rib guide was evaluated and the validity of the method is confirmed by comparison with published experimental results.
Vector basis functions in mixed‐potential integral equation method
Authors: Matsuhara Masanori , Angkaew Tuptim 
Published: July 2007

AbstractThe mixed potential integral equation (MPIE) is one of the principal numerical analysis methods used for the computer‐aided design of microwave and millimeter‐wave integrated circuits. In this paper, a systematic method for constructing the vector basis functions used in the MPEE is described and application examples are presented. A systematic technique for constructing the first‐ and second‐order vector basis functions is presented. This method is applied to the MPIE for numerical analysis of a patch antenna; the results demonstrate the validity and the effectiveness of the vector basis functions.
Realization of high‐performance MOSFETs with gate lengths of 0.1 μm or less
Authors: Momose Hisayo Sasaki , Ono Mizuki , Yoshitomi Takashi , Ohguro Tatsuya , Saito Masanobu , Iwai Hiroshi , Nakamura Shin‐Ichi 
Published: July 2007

AbstractThe reduction of gate length improves the performance of a MOSFET. However, this is difficult to do when the gate length is less than 0.1 μm for numerous reasons.This paper reports the results of improvement of the MOSFET performance employing various means. It was found that the current drive was only 30 percent higher with a gate length of 40 nm than with a gate length of 0.1 μm. Even when the gate oxide was 1.5 nm, which is half the oxide thickness for a direct tunneling leakage limit, it was found that the MOSFETs operate normally and the current drive was 1.6 times higher than when the gate oxide was 3 nm, because of the increase of gate capacitance.When a low‐doped thin Si epitaxial layer was used as the intrinsic channel, the channel drive was improved by 20 percent because of higher carrier mobility, compared with the current‐driving efficiency of a MOSFET formed by bulk material. The problem of source drain parasitic resistance increase in small‐geometry MOSFETs was solved by using a novel device structure, i.e., S4D. Using this new structure, the parasitic resistance was reduced by one order of magnitude. Combining the aforementioned techniques, the current‐driving efficiency could be improved further even when the gate length is in the sub‐0.1 μm region.
Boundary integral equations for computer aided design of near‐field optics
Authors: Tanaka Masahiro , Tanaka Kazuo 
Published: July 2007

AbstractNew forms of boundary integral equations are proposed for computer aided design (CAD) and simulation of near‐field optical circuits. These integral equations can be easily solved numerically by using the boundary element method or moment method without using complicated mode‐expansion techniques for open waveguide structures. As an example, the new equations are used to design a two‐dimensional optical particle manipulator, and the effectiveness and correctness are demonstrated by numerical results.
Reliability simulation of AC hot carrier degradation for deep sub‐micron MOSFETs
Authors: Shimizu Satoshi , Tanizawa Motoaki , Kusunoki Shigeru , Inuishi Masahide , Miyoshi Hirokazu 
Published: July 2007

AbstractHigh performance under low supply voltage is required for ULSIs in combination with the higher packing density that results from scaling down to the deep sub‐micron region. For this requirement, the conventional method, using the DC hot carrier lifetime of MOSFETs as measured by DC stress, overestimates the degradation caused by real circuit operation. As a result, the improvement of MOSFET performance is limited by attempting to satisfy the overestimated hot carrier criteria under DC stress. Therefore, it is strongly desired that the reliability simulation estimate accurately hot carrier degradation in real circuit operation. We have found that the degradation rate depends on the stress conditions and can be expressed in terms of the difference between the gate and drain voltages. Hence, in this paper, we propose a new method of modeling and calculation of hot carrier degradation that incorporates this dependence and will demonstrate improved accuracy in predicting degradation and life time for both AC and DC bias conditions. We also propose a new duty ratio extraction method that can be used to predict the lifetime for hot carrier degradation under actual circuit operation.
Dielectric properties of thermally aged poly aniline films doped with dilute sulfuric acid
Authors: Tsubakihara Hiroshi , Hasimoto Hideyuki , Okamura Hiroshi , Hayashi Kohtaku 
Published: July 2007

AbstractAn experimental study of the frequency‐dependent dielectric properties of thermally aged polyaniline (pAn) films as a function of the concentration of the sulfuric acid solution used for dipping was performed. Inferring the morphological changes of the films from the results of ultraviolet‐visible (UV‐vis) and infrared (IR) absorption spectra and differential scanning calorimetry (DSC) ther‐mograms, the dependency of the dielectric properties of thermally aged films on the protonation level is discussed. The effects of thermal aging on dielectric properties may be subdivided into two temperature regions. In the temperature range lower than 170°C, the dielectric constant was decreased, especially at high frequencies, and the tan δ‐peak was shifted to lower frequencies with increasing aging temperature. The mobility of pAn chains and electric dipole appears to be gradually restricted with increasing temperature. In the range higher than 210°C, pAn cannot be protonated and the dielectric properties are unaltered by dipping in dilute sulfuric acid (pH = 2), owing to crosslink‐ing and oxidation of imine nitrogens.
Fabrication of SiN films at low temperature by RF biased coaxial‐line microwave plasma CVD
Authors: Morita Yoshinori , Kato Isamu , Nakajima Tatsuji 
Published: July 2007

AbstractThis paper discusses the influence of ion bombardment on the characteristics of SiN films. In this study, the double‐tube coaxial‐line microwave plasma CVD system, which is suitable for the investigation of ion bombardment, is used to deposit SiN films. The ion bombardment energy is varied by varying die RF bias at constant ion density. As the RF bias is increased, the film density increases and the hydrogen concentration decreases, but the dangling bond density increases. The increase in the film density and decrease of hydrogen concentration are caused by the increase in film surface temperature, while the increase of the dangling bond density is caused by bond breakage due to me N+ ion implantation. When the substrate temperature is 200°C and the RFbias is −175 V, the film density is 3 g/cm3 and the hydrogen concentration is 9 at.% because of the film surface heating effect of ion bombardment and also due to substrate heating. Substrate heating at 200°C suppresses the increase in the dangling bond density. It is also demonstrated that the film surface temperature is about 200°C when RF bias is −70–80 V and the substrate is unheated by any heater.
A synthesis of an LC simulation—type double‐tuned circuit adjustable by a single parameter
Authors: Nakamura Masataka , Okine Mitsuo , Shigehiro Takanori , Unehara Takashi 
Published: July 2007

AbstractIn this paper we derive a double‐tuned, narrow‐band transfer function and illustrate its LC simulation‐type active realization with low element sensitivity. First, a new double‐tuned function that is adjustable by a single parameter is derived for a circuit using mutual induction. Next, the basic circuit that generates negative feedback with RLC elements and controlled sources is derived. This basic circuit can have a low element sensitivity within the passband, as confirmed by the numerical analysis. As an example of the implementation for the basic circuit, an active RC circuit with the center frequency f0 = 455 kHz and Q = 30 is constructed; transistor gyrators are used for L element simulation; and a single variable resistor is used for the coupling coefficient adjustment. The experimental tuned characteristics for several coupling coefficients are in good agreement with the calculated values.
Experiments on transmitting and receiving an ultrasonic pulse train with stacked piezoceramic transducers
Authors: Imano Kazuhiko , Kawazu Hidekatsu , Inoue Hiroshi 
Published: July 2007

AbstractIn ultrasonic flaw detection and medical diagnosis, shorter pulses tend to be used for improvement of the time resolution. It is then necessary that the transmitting and receiving systems have large bandwidth. In order to obtain information from the ultrasonic wave in the propagation direction over a long distance, a pulse with high peak power needs to be used so that the S/N is enhanced. However, it is not simple to attain the requirements for both large bandwidth and high S/N. In this paper, a system is proposed in which, instead of using short pulses, the transmitted pulses are combined into a pulse train and pulse compression is carried out on the receiving side by a correlation process, so that short pulse transmission is realized effectively. First, we describe the generation of an ultrasonic pulse train using a stacked piezoceramic transducer made of several piezo‐ceramic resonators without complex electronic circuits. We next describe the principle of the reception correlation process, using stacked transducers with the same characteristics. We fabricated stacked transducers for transmission and reception of an ultrasonic pulse train with a Barker code of length 7. Transmission and reception experiments show that both the transmission of the pulse train and the correlation process are possible. Transmission and reception experiments were carried out under different S/N conditions by adding external noise to the input. When the S/N ratio of the transmitting pulse train was 0 dB, a gain of 4.6 dB was obtained. The gain margin was found to be 7.2 dB. Hence, it was demonstrated that the present method is effective under low S/N conditions.
A voltage‐controlled resistor for a linear voltage‐controlled oscillator
Authors: Teramura Masahiro , Miyazaki Tomoyuki , Hone Yuuji , Takeishi Taisuke 
Published: July 2007

AbstractTo realize a linear voltage‐controlled oscillator (VCO), a voltage‐controlled resistor (VCR) whose reciprocal resistance is linear with respect to the control voltage Vcwas fabricated and tested. The VCR was composed of an analog multiplier (AM) and an operational amplifier (OA). The. static effective resistanceReof the VCR varied asR−1e=R−1(1 + αVc), whereRis the feedback resistance used in the VCR and α the scale factor of the AM. As for die dynamic characteristics, the reciprocal of the effective resistance of the VCR was not linear with respect toVcat high frequencies or for low control voltages, which resulted from an equivalent reactance of the VCR caused by the time lag at both the AM and the OA. Experimental testing of the Wien bridge oscillator with the VCRs showed that the oscillation was stable and that the frequency of oscillation varied linearly withVc.
Impact of high‐temperature rapid thermal annealing in deep‐submicrometer CMOSFET design
Authors: Shimizu Akihiro , Ohki Nagatoshi , Ishida Hiroshi , Yamanaka Toshiaki , Kikushima Ken‐Ichi , Okuyama Kousuke , Kubota Katsuhiko , Koike Atsuyoshi 
Published: July 2007

AbstractWe investigated the impact of high‐temperature rapid thermal annealing (HT‐RTA) for CMOSFET design in the deep‐submicrometer regime. HT‐RTA (>1000 °C) carried out immediately after ion implantation can reduce the transient enhanced diffusion of implanted impurities and suppress interactions between these impurities, both of which are usually observed in low‐temperature furnace annealing processes. HT‐RTA is definitely effective in CMOSFET design optimization, since it can control impurity profiles more precisely than conventional thermal processes, leading to improvements in the short‐channel effects, current drivability, and reliability of MOSFETs. We also show that HT‐RTA serves as a methodology for analyzing the RSCE (reverse short‐channel effects) and ESCE (enhanced short‐channel effects) taking place simultaneously in deep‐submicrometer MOSFETs.
The flawed four‐level evaluation model
Authors: Holton Elwood F. 
Published: July 2007

AbstractThe lack of research to develop further a theory of evaluation is aglaring shortcoming for human resource development (HRD). In this paper, 1 argue that the four‐level system of training evaluation is really a taxonomy of outcomes and is flawed as an evaluation model Research is needed to develop a fully specified and researchable evaluation model. Such a model needs to specify outcomes correctly, account for the effects of intervening variables that affect outcomes, and indicate causal relationships. I propose a new model based on existing research and accounts for the impact of the primary intervening variables such as motivation to learn, trainability, job attitudes, personal characteristics, and transfer of training conditions. A new role for participant reactions is specified. Key studies supporting the model are reviewed and a research agenda proposed.
The Relationship Between Organizational Factors and the Transfer of Training in the Electronics Industry in Shenzhen, China
Authors: Xiao Jin 
Published: July 2007

AbstractThis study was conducted in four electronics companies in Shenzhen, China. It employs a transfer model that argues that training develops only potential capacity in trainees. The transfer of training in the workplace depends on organizational factors that facilitate the utilization of knowledge, skills, and attitudes (KSA) gained in the training setting.Analyses indicate that training, recently adopted nationwide in industry in China, is related to transfer behavior. In addition, organizational variables that encourage application of KSA in the workplace promote the transfer of training. Among the organizational variables, supervision appears to be the most influential.The study's findings also suggest that management concepts and practices for organizing a modern workplace are important in improving productivity in a newly developed industria! zone in China.
How executive women learn corporate culture
Authors: Bierema Laura L 
Published: July 2007

AbstractThis article reports on a qualitative case study that investigated how executive women learn corporate culture. This study was inspired by the fact that jew female executives inhabit corporate America and representation of women at the highest levels of American business has remained stagnant. The study indicated that women see organizational culture as male‐centered and use learning as a strategy to negotiate through this sometimes inhospitable environment. The women who participated in the study learned cognitively, experientially, and collaboratively about organizational culture, implications for executive female development and HRD are discussed.