bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analysis of Scattering Light from Magnetic Material with Land/Groove by Three-Dimensional Boundary Element Method
Authors: Ogawa Masatsugu , Nakada Masafumi , Katayama Ryuichi , Mitsuya Okada Mitsuya Okada , Masaki Itoh Masaki Itoh 
Published: October 2002

A calculation method with three-dimensional Boundary Element Method (BEM) has been developed for analyzing scattering light from a magnetic material, in order to determine the contribution of land/groove shapes and incident beam polarization to Kerr rotation. A product of scattering beam intensity and the Kerr rotation angle (R·θ
k
) has been calculated in the case that 680 nm wavelength Gaussian beam is focused on 680 nm or 1360 nm width land/groove, which has 85 nm depth or height. The land or groove shapes have been varied from rectangular shapes to V-shapes. Regardless of the land/groove shapes, the R·θ
k
of lands is larger than that of grooves in TM-polarization and smaller in TE-polarization. The results in verification experiments well met the calculated ones, i.e., the carrier level of lands is higher than that of grooves in almost the entire range of recording frequency for TM-polarization light, and it is lower for TE-polarization.
A Rigorous Series Solution for Diamond Heat Spreaders with Temperature-Dependent Thermal Conductivity Used in Microwave Power Devices
Authors: Hui Ping , Tso Chih Ping , Hong Siang Tan Hong Siang Tan 
Published: October 2002

In this paper we derive a rigorous series solution of the nonlinear heat transfer equation using the modified Kirchhoff transformation for a cylindrical diamond heat spreader with temperature-dependent thermal conductivity, situated on the top of a copper heat sink. We point out what we believe to be errors in two analytical approaches applied to the same problem which were published recently [Proc. R. Soc. Lond. A 441 (1993) 181; Proc. R. Soc. Lond. A 445 (1995) 375; and IEEE Trans. Microwave Theor. & Technol. 42 (1994) 573]. The basic difference between our work and these previous studies lies in the boundary condition (b.c.) of the transformed heat potential over the spreader-sink interface–we use nonlinear b.c. whereas the boundary conditions in the previous studies have been assumed to be linear. Calculations of change in the thermal resistance with the geometrical dimensions of the spreader, the input power, and the ambient temperature show up the profound influence which the assumed b.c. have on the problem. Our study has also revealed errors in numerical results presented in another paper [IEEE Semi-Therm Proc. (4th Annu. Semiconductor Thermal and Temperature Measurement Symp.), p. 113].
Anomalous Heat Evolution of Deuteron-Implanted Al upon Electron Bombardment
Authors: Kamada Kohji , Kinoshita Hiroshi , Takahashi Heishitiro 
Published: October 2002

Anomalous heat evolution was observed for the first time in deuteron-implanted Al foils upon 175 keV electron bombardment. Local regions with linear dimension of more than 100 nm showed simultaneous transformation from single-crystalline to polycrystalline structure within roughly one minute during the electron bombardment, indicating a temperature rise to above the melting point of Al from room temperature. The amount of energy evolved was estimated to be typically 160 MeV for each transformed region. The transformation was never observed in proton-implanted Al foils. Microstructures in the subsurface layer of the implanted Al, investigated by elastic recoil detection (ERD) method and transmission electron microscopy (TEM), were presented for numerical discussions of the experimental results. Possible causes of the surface melting, such as the heating effect of the electron beam, size effect of the melting point, difference in the implanted depth profiles between hydrogen and deuterium, and possible chemical reactions due to the electron bombardment in D2collections, were investigated. We consider that some kind of nuclear reaction occurring in the D2collections is the only explanation for the observed melting. The reaction was estimated to continue only for a short time, presumably less than 10-10s, and the energy gain, which is defined as the ratio between the amount of energy evolved and the energy loss of the impinging electros through the Al specimen, amounts to more than 1×105.
Development of Sub-Quarter-µm MONOS (metal/oxide/nitride/oxide/semiconductor) Type Memory Transistor
Authors: Thomas Böhm Thomas Böhm , Akihiro Nakamura Akihiro Nakamura , Hiroshi Aozasa Hiroshi Aozasa , Machio Yamagishi Machio Yamagishi , Yasutoshi Komatsu Yasutoshi Komatsu 
Published: October 2002

A MONOS (metal/oxide/nitride/oxide/semiconductor) type nonvolatile memory transistor with a gate length of 0.23 µm has been developed. This memory transistor offers high endurance, low programming voltage and a narrow distribution of programmed threshold voltages. By introducing a rapid thermal nitridation (RTN) step into the fabrication prosecc of the ONO (oxide/nitride/oxide) layer, an enhancement in erase speed of one order of magnitude is achieved. The RTN also improves the oxidation resistance of the nitride layer, so that scaling down the thickness of the ONO film in order to reduce the programming voltage is feasible.
A 4:1 MUX Circuit Using 1/4 Micron CMOS/SIMOX for High-Speed and Low-Power Applications
Authors: Sadayuki Yasuda Sadayuki Yasuda , Yusuke Ohtomo Yusuke Ohtomo , Masayuki Ino Masayuki Ino , Yuichi Kado Yuichi Kado , Hiroshi Inokawa Hiroshi Inokawa , Toshiaki Tsuchiya Toshiaki Tsuchiya 
Published: October 2002

We designed a new 4:1 multiplexer (MUX) circuit and fabricated it by 0.25-µm CMOS device process technology using Separation by IMplanted OXygen (SIMOX) wafer. This MUX circuit has a small number of fan-outs so that the SIMOX device, with smaller junction capacitance than a BULK device, effectively contributes to high-speed and low-power operation. We confirmed that the fabricated SIMOX MUX can operate at 2.7 GHz (@V
DD = 2.0 V), which is 25% faster than the BULK MUX, and the power consumption is 19% less at the same speed and V
DD. In addition, we confirmed that these improvements are mainly due to the reduced junction capacitance of SIMOX devices by estimating the gate speed in the critical path and the load capacitance in the SIMOX MUX circuit.
Room-Temperature Operation of DC Axially Discharged Fast Axial-Flow CO Laser
Authors: Yutaka Kodama Yutaka Kodama , Heihachi Sato Heihachi Sato 
Published: October 2002

A compact CO laser with a DC axially discharged fast-axial flow has been operated at room temperature (270 – 300 K), achieving ∼ 165 W per unit discharge length in CW mode under xenon (Xe) gas addition. A maximum power of 385 W per unit gain length (1 m) has been similarly achieved with Xe gas at 235 – 275 K. Dependence of output power on gas-flow velocity v , discharge current I
dis, and gas composition is examined experimentally and theoretically explained, and dependence of oscillation lines on v is also investigated. Moreover, the effect of gas-flow velocity on gas temperature is also examined.
Electron Energy-loss Spectroscopy Study of the Metal-insulator Transition in VO 2
Authors: Hiroyuki Abe Hiroyuki Abe , Masami Terauchi Masami Terauchi , Michiyoshi Tanaka Michiyoshi Tanaka , Shik Shin Shik Shin , Yutaka Ueda Yutaka Ueda 
Published: October 2002

Electron energy-loss spectra of VO2 have been measured from perfect single crystalline areas of 100–180 nm diameter in the metallic and insulating phases. A sharp peak has been observed at 1.2 eV in the valence electron excitation spectra of the metallic phase but not in those of the insulating phase. We assign the peak to an interband transition or d-d transition by inspecting the dielectric function derived from the present loss function with the help of an energy band diagram already given, although an excitation at about 1 eV already observed by optical measurement was assigned to the excitation of a free-carrier plasmon. The peak due to the O 1s → V 3d(t
2g
) transition in the O 1s excitation spectra decreased in intensity but increased in the full width at half-maximum (FWHM) at the transition from the metallic phase to the insulating phase. These changes are considered to have been due to the fact that the d
\varparallel band splits into the upper unoccupied and lower occupied d
\varparallel bands and the upper d
\varparallel band rises above the π* band in the insulating phase, but that the d
\varparallel band is unsplit and located within the π* band in the metallic phase.
Nucleation Control in the Growth of Bulk GaN by Sublimation Method
Authors: Satoshi Kurai Satoshi Kurai , Katsushi Nishino Katsushi Nishino , Shiro Sakai Shiro Sakai 
Published: October 2002

Nucleation of GaN crystallites by sublimation method on sapphire (0001), scratched sapphire (0001), SiO2, Si (111), and metalorganic chemical vapor deposition(MOCVD)-GaN/sapphire (0001) was investigated. The density of the nuclei on SiO2 and Si (111) was estimated to be 6 × 103/cm2. On the other hand, a continuous film rather than discrete crystallites was obtained on both the MOCVD-GaN and the scratched sapphire. Growth nucleation control was performed by partly covering the MOCVD-GaN or scratched sapphire (0001) with SiO2. As a result, hexagonal columns about 200 µm in diameter and 200 µm high were selectively and uniformly grown at the window sites. The diameter of each hexagonal column was much larger than the width of each window. This method can be used for device processing utilizing the crystallites.
Characterization of Domain-Inverted Layers in LiTaO 3 by Line-Focus-Beam Acoustic Microscopy
Authors: Jun-ichi Kushibiki Jun-ichi Kushibiki , Masahito Miyashita Masahito Miyashita 
Published: October 2002

A characterization procedure of domain-inverted layers employed in LiTaO3 optoelectronic devices by line-focus-beam acoustic microscopy is explored. A special specimen of -Z-cut LiTaO3 with a domain-inverted layer of about 1.8 µm thickness, processed under the fabrication conditions for quasi-phase-matching second-harmonic-generation devices, was prepared for measurements of the leaky surface acoustic wave (LSAW) velocities in the frequency range 100 to 300 MHz. Intrinsic decreases in LSAW velocity were obtained with the rate of 0.127 m/s/MHz, which were in excellent agreement with the theoretical results. These resulted from formation of a domain-inverted layer on the -Z surface. Slight variations in domain-inverted depth on the specimen, caused by variation in process temperature, were also detected, with the measurement resolution of 0.01 µm at 225 MHz.
Defect Analysis in Bonded and H + Split Silicon-on-Insulator Wafers by Photoluminescence Spectroscopy and Transmission Electron Microscopy
Authors: Michio Tajima Michio Tajima , Atsushi Ogura Atsushi Ogura , Tomoki Karasawa Tomoki Karasawa , Atsushi Mizoguchi Atsushi Mizoguchi 
Published: October 2002

Defects in silicon-on-insulator wafers fabricated by bonding and H+
splitting technique
(Unibond wafers [Unibond is a registered trademark of SOITEC.]) were characterized by photoluminescence (PL)
spectroscopy
together with transmission electron microscopy (TEM).
PL from the superficial Si layer and that from the supporting substrate
were separately
analyzed using UV and visible light as an excitation source, respectively.
The deep-level PL band appeared around 0.8 eV both in the superficial
layer and the
substrate with a spectral shape similar to that often observed in oxygen
precipitated Si
crystals.
Correspondingly, TEM observation revealed precipitates and related
defects.
These results allow us to conclude that the defects in Unibond wafers originate in
oxygen precipitation during the two-step annealing in the wafer
fabrication process.
Confinement of Nonneutral Plasmas in a Trap Composed of a Cusped Magnetic Field and an Electrostatic Octapole Field
Authors: Akihiro Mohri Akihiro Mohri , Tetsumori Yuyama Tetsumori Yuyama , Yasuhito Kiwamoto Yasuhito Kiwamoto , Yohei Yamazawa Yohei Yamazawa , Toshinori Michishita Toshinori Michishita 
Published: October 2002

The field configuration formed by the superposition of a cusped
magnetic field and an electrostatic octapole field provides a closed
system of confinement for a charged particle. In a cusped magnetic
field, the Störmer region which constrains a charged particle is
open, but it is closed by adding a potential barrier made by the
octapole field. One-component plasmas are thus expected to be
confined in this configuration, preserving superior characteristics
of the cusp field for plasma stability. A preliminary experiment was performed on the confinement of electrons in this
field configuration. An electron plasma was confined
for 3 s in a magnetic field as weak as B=50 G at the
circular line cusp. The confinement time was roughly proportional
to B
2, suggesting that the confinement would be improved substantially in
a higher magnetic field.
Generation and Detection of Squeezed Light with Phase Tunable Fiber Loop Mirror using Polarization Beam Splitter
Authors: Norihiko Nishizawa Norihiko Nishizawa , Masaki Hashiura Masaki Hashiura , Takeo Horio Takeo Horio , Masakazu Mori Masakazu Mori , Toshio Goto Toshio Goto , Kazuo Yamane Kazuo Yamane 
Published: October 2002

Squeezed light generation is demonstrated using a new scheme of nonlinear
fiber loop mirror.
The squeezed light can be generated stably in a compact setup
and the phase difference can be changed arbitrarily.
Using a 100 ps mode-locked pulse laser at 1.064 µm and 0.85 µm
single-mode fiber, the quantum noise reduction of 2.0 dB below the shot noise level
is observed in the frequency range of 25–35 MHz.
Accounting for the detection efficiency, this corresponds to 2.9 dB squeezing.
Lithography Simulator for Electon Beam/Deep UV Intra-Level Mix & Match
Authors: Ryoichi Inanami Ryoichi Inanami , Tetsuro Nakasugi Tetsuro Nakasugi , Shinji Sato Shinji Sato , Shoji Mimotogi Shoji Mimotogi , Satoshi Tanaka Satoshi Tanaka , Kazuyoshi Sugihara Kazuyoshi Sugihara 
Published: October 2002

We have developed an electron beam/deep UV (EB/DUV) intra-level
mix & match (IL M&M) lithography simulator.
In the simulator,
for EB and DUV exposure pattern to be exposed in the same resist layer
in IL M&M lithography process,
(1) energy distributions deposited by the EB and the DUV exposures
are calculated in respective simulators separately.
(2) The two energy distributions are blurred respectively
by the Gaussian convolution whose standard deviation is called
a lithography process parameter, ΔL.
(3) The two blurred energy distributions are superposed on each other.
(4) Development calculation is performed.
The propriety of these calculations was confirmed by contrast
with a corresponding experiment.
By demonstrating two examples of the application of the simulator,
the simulator is shown to be a helpful tool for precognition of
results obtained by applying the EB/DUV IL M&M lithography process.
The simulator is essential for optimizing the various conditions
in the EB/DUV IL M&M lithography.
Magnetic Damping of the Temperature-Driven Convection in NaCl Aqueous Solution Using a Static and Homogeneous Field of 10 T
Authors: D. Durbin Gen Sazaki , Satoru Miyashita Satoru Miyashita , Toru Ujihara Toru Ujihara , Kazuo Nakajima Kazuo Nakajima , Mitsuhiro Motokawa Mitsuhiro Motokawa 
Published: October 2002

Temperature-driven convection in 25 wt% NaCl
aqueous solution was observed in situ under a static and homogeneous
magnetic field of 10 T.
The convection in the solution was visualized using polystyrene latex particles
of 5 µm diameter.
A magnetic field of 10 T reduced the velocity of convection by a factor of two.
Magnetic damping of convection in an electrolyte solution could be a useful
technique to control the growth of crystals such as proteins.
Sub-10 nm Linewidth and Overlay Performance Achieved with a Fine-Tuned EBPG-5000 TFE Electron Beam Lithography System
Authors: Bernd E. Maile Bernd E. Maile , Wolfgang Henschel Wolfgang Henschel , Heinrich Kurz Heinrich Kurz , Bert Rienks Bert Rienks , Roelof Polman Roelof Polman , Piet Kaars Piet Kaars 
Published: October 2002

A Leica EBPG-5000 TFE electron beam lithography system has been evaluated and optimized. Sources of beam positional noise have been eliminated, resulting in an effectively useable spot size of less than 6 nm. Hydrogen silsesquioxane (HSQ) negative resist shows excellent resolution in combination with the fine-tuned instrument. Linewidths smaller than 8 nm have been reproducibly achieved at 100 kV under relaxed processing conditions, making HSQ an excellent test vehicle for system benchmarking in the nanometer regime. Using ultra-small vernier patterns exposed in HSQ resist, the intrinsic overlay accuracy of the system has been determined. A |mean| + 2 σ value better than 4 nm has been obtained.
Characteristics of Interface-Modified Josephson Junctions Fabricated under Various Etching Conditions
Authors: Masahiro Horibe Masahiro Horibe , Yukitoshi Inagaki Yukitoshi Inagaki , Kazuhiro Yoshida Kazuhiro Yoshida , Gen-ichiro Matsuda Gen-ichiro Matsuda , Noriyoshi Hayashi Noriyoshi Hayashi , Akira Fujimaki Akira Fujimaki , Hisao Hayakawa Hisao Hayakawa 
Published: October 2002

We have studied the influence of process parameters on electrical properties for interface-modified junctions (IMJs) based on YBa2Cu3Ox.
Tunnel barriers are produced by an electron cyclotron resonance (ECR) plasma etching process and subsequent vacuum annealing.
We have found that time and accelerating voltage (V
acc) in the etching sequence,
in which the ramp-edge geometry is defined, are very important parameters for the barrier formation.
Increasing the etching time and accelerating voltage lead to the reduction of critical current densities.
By setting these parameters at appropriate values, we can control the critical current of the IMJs.
We have also found that the IMJs with high junction resistance, which are fabricated at higher accelerating voltages above 700 V, have transport mechanisms via localized states for quasi particles.
The X-ray photo spectroscopy analysis suggests that accelerating voltages above 700 V enhance the thickness of the barrier, while those below 700 V affect both barrier resistivity and thickness.
Photoinduced Valence Changes of Samarium Ions Inside a Silica-Based Glass with Near- Infrared Femtosecond-Laser Pulses: Materials for Three-Dimensional Optical Memory
Authors: Koji Fujita Koji Fujita , Kazuyuki Hirao Kazuyuki Hirao 
Published: October 2002

We report photoinduced valence changes of samarium ions inside a silica-based glass using focused femtosecond-laser pulses of 800 nm wavelength. Photoluminescence spectra reveal that femtosecond-laser irradiation reduces Sm3+ in the vicinity of the focal point of the laser beam to Sm2+. The mechanism of the photoinduced reduction of Sm3+ is discussed based on optical absorption and electron spin resonance spectra.
Radio Emission from Supernovae and Gamma-Ray Bursters
Authors: Weiler Kurt W. , Panagia Nino , Montes Marcos J. , Sramek Richard A. 
Published: October 2002

▪ Abstract  Study of radio supernovae over the past 20 years includes two dozen detected objects and more than 100 upper limits. From this work it is possible to identify classes of radio properties, demonstrate conformance to and deviations from existing models, estimate the density and structure of the circumstellar material and, by inference, the evolution of the presupernova stellar wind, and reveal the last stages of stellar evolution before explosion. It is also possible to detect ionized hydrogen along the line of sight, to demonstrate binary properties of the stellar system, and to show clumpiness of the circumstellar material. More speculatively, it may be possible to provide distance estimates to radio supernovae. Over the past four years the afterglow of gamma-ray bursters has occasionally been detected in the radio, as well in other wavelengths bands. In particular, the interesting and unusual gamma-ray burst GRB980425, thought to be related to SN1998bw, is a possible link between supernovae and gamma-ray bursters. Analyzing the extensive radio emission data avaliable for SN1998bw, one can describe its time evolution within the well-established framework available for the analysis of radio emission from supernovae. This allows relatively detailed description of a number of physical properties of the object. The radio emission can best be explained as the interaction of a mildly relativistic (Γ ∼ 1.6) shock with a dense preexplosion stellar wind–established circumstellar medium that is highly structured both azimuthally, in clumps or filaments, and radially, with observed density enhancements. Because of its unusual characteristics for a Type Ib/c supernova, the relation of SN1998bw to GRB980425 is strengthened and suggests that at least some classes of GRBs originate in massive star explosions. Thus, employing the formalism for describing the radio emission from supernovae and following the link through SN1998bw/GRB980425, it is possible to model the gross properties of the radio and optical/infrared emission from the half-dozen GRBs with extensive radio observations. From this we conclude that at least some members of the “slow-soft” class of GRBs can be attributed to the explosion of a massive star in a dense, highly structured circumstellar medium that was presumably established by the preexplosion stellar system.
Contributions of Subregions of the Prefrontal Cortex to Working Memory: Evidence from Brain Lesions in Humans
Authors: Müller Notger G. , Machado Liana , Knight Robert T. 
Published: October 2002

AbstractWe investigated working memory in patients with focal brain damage involving subregions of the prefrontal cortex (PFC). Lesions in the dorsal portion of lateral PFC or the ventromedial portion of orbital PFC did not impair performance in tasks that required maintenance and monitoring of object or spatial information. Larger lesions involving both ventral and dorsal parts of the lateral PFC impaired maintenance and monitoring of spatial and object information, with more severe deficits observed in the spatial tasks. The results support a distributed localization of function in lateral PFC during working memory.