著者
Park Wug-Dong Tanioka Kenkichi
出版者
Published by the Japan Society of Applied Physics through the Institute of Pure and Applied Physics
雑誌
Japanese journal of applied physics. Pt. 1, Regular papers & short notes (ISSN:00214922)
巻号頁・発行日
vol.42, no.4, pp.1954-1956, 2003-04-15
被引用文献数
11

In this paper, spectral responses of Te-doped a-Se HARP (High-gain Avalanche Rushing amorphous Photoconductor) thin films for a solid state image sensor have been reported. Te concentrations of Te-doped layer in a-Se HARP thin film were 15 wt.% and 26 wt.%, and thicknesses of Te-doped layer were 60 nm, 90 nm, and 120 nm. Spectral responses of Te-doped a-Se HARP films were investigated at bias voltages of 40 V and 60 V. Relative sensitivity and quantum efficiency of a-Se HARP films at 60 V were found to be improved by the increase of Te-doped layer thickness. This improvement is explained by the increased photogeneration efficiency at long wavelength region by the increase of Te-doped layer thickness and avalanche multiplication of the photogenerated carriers at a high electric field.
著者
MIURA Noboru KAWANISHI Mitsuhiro MATSUMOTO Hironaga NAKANO Ryotaro
出版者
社団法人応用物理学会
雑誌
Japanese journal of applied physics. Pt. 2, Letters (ISSN:00214922)
巻号頁・発行日
vol.38, no.11, pp.L1291-L1292, 1999-11-15
被引用文献数
63 94

The high-luminance blue emitting electroluminescent (EL) devices which have been satisfied with the requirement for full color displays were obtained. BaAl_2S_4:Eu thin-film EL devices as the new blue emitting EL phosphor was prepared by the two targets pulse-electron-beam evaporation. The maximum luminance level was 65 cd/m^2 under the 50 Hz-pulse voltage. The EL spectrum had a blue emission band with a peak around 475 nm due to the 5d-4f transition for Eu^<2+> ion. The Commission Internationale de l'Eclairage (CIE) color coordinates of BaAl_2S_4:Eu EL device were x=0.12 and y=0.10.
著者
YANG L. W. WRIGHT P. D. SHEN H. LU Y. BRUSENBACK P. R. KO S. K. CALDERON L. HARTZLER W. D. HAN W. Y. DUTTA M. CHANG W. H.
出版者
社団法人応用物理学会
雑誌
Japanese journal of applied physics. Pt. 2, Letters (ISSN:00214922)
巻号頁・発行日
vol.32, no.10, pp.L1400-L1402, 1993-10-01
被引用文献数
1

Submicron heterojunction bipolar transistors (HBTs) with maximum frequency of oscillation, f_<MAX>, of 91 GHz have been fabricated using a self-aligned technique and a very heavily carbon-doped (10^<20> cm^<-3>) base layer. Since the quenching of photoluminescence (PL) intensity in heavily-doped Cabs is mainly due to nonradiative recombination in the bulk material, while contribution from surface recombination is negligible, the use of a heavily carbon-doped base layer in AlGaAs/GaAs HBTs minimizes the influence of surface recombination in the extrinsic base region. Thus, for HBTs with a heavily doped base layer, the "emitter size effect" (degradation of HBT current gain) is greatly reduced when the emitter width is scaled down to submicron (0.6 μm) dimensions.
著者
Mohan Rajneesh Kim Sang-Jae
出版者
Published by the Japan Society of Applied Physics through the Institute of Pure and Applied Physics
雑誌
Jpn J Appl Phys (ISSN:00214922)
巻号頁・発行日
vol.50, no.4, pp.04DJ01-04DJ01-4, 2011-04-25
被引用文献数
4

In this paper, the resistive switching effects in ZnO whiskers are reported. The resistive switching properties were studied by current controlled current--voltage ($I$--$V$) sweeps. On increasing the biasing current value, the resistance of the ZnO whiskers switches from high resistance state (HRS) to low resistance state (LRS). Between the HRS and LRS, anomalous resistance fluctuations were observed during the resistive transition. These resistive switching effects were studied for ZnO whiskers of different diameters. It was observed that resistive switching depends on the diameter of the ZnO whisker. As the diameter of a ZnO whisker decreases, the resistance switching increases. The mechanism of the observed resistive switching is also proposed.
著者
Kobune Masafumi Teraoka Kenji Nishioka Hiroshi Yamaguchi Hideshi Honda Koichiro
出版者
Published by the Japan Society of Applied Physics through the Institute of Pure and Applied Physics
雑誌
Jpn J Appl Phys (ISSN:00214922)
巻号頁・発行日
vol.50, no.9, pp.09ND08-09ND08-5, 2011-09-25
被引用文献数
7

Perovskite-structured solid solutions with compositions of 0.9963{($1-x$)(Bi<sub>1/2</sub>Na<sub>1/2</sub>)TiO<sub>3</sub>--$x$Ba(Cu<sub>1.1/3</sub>Nb<sub>2/3</sub>)O<sub>3</sub>} + 0.0037MnO<sub>2</sub>, with $x = 0{\mbox{--}}0.06$ [abbreviated as ($1-x$)BNT--$x$BCN)], were fabricated by normal sintering, and their structural, and piezo- and ferroelectric properties were investigated in detail. The X-ray diffraction profiles of the ($1-x$)BNT--$x$BCN solid solutions with $x = 0{\mbox{--}}0.06$ suggested that the rhombohedral-tetragonal morphotropic phase boundary (MPB) in this material system is in the compositional region $x = 0.0425{\mbox{--}}0.0460$. The cross-sectional transmission electron microscopy (TEM) images and selected-area electron diffraction (SAED) patterns of the ($1-x$)BNT--$x$BCN samples with $x = 0.0475$ suggested that the present materials have a modulation structure arranged by a double period along the [111] direction. It is shown that the tetragonal BNT--BCN ($x = 0.0475$) solid solution with a composition of 0.9490BNT$\Cdot$0.0473BCN$\Cdot$0.0037MnO<sub>2</sub>near the MPB has a piezoelectric coefficient ($d_{33}$), a relative permittivity ($\varepsilon_{33}{}^{\text{T}}/\varepsilon_{0}$), and a remanent polarization ($P_{\text{r}}$) of approximately 1.8, 3.2, and 2.8 times larger, respectively, than those of the BNT solid solution without BCN substitution.
著者
FUNAKI Kazuo NIDOME Teruhide YAMAFUJI Kaoru
出版者
社団法人応用物理学会
雑誌
Japanese journal of applied physics. Pt. 1, Regular papers & short notes (ISSN:00214922)
巻号頁・発行日
vol.21, no.8, pp.1121-1126, 1982-08-20
被引用文献数
29

In a nonideal superconducting wire, a number of strange magnetic phenomena have been observed in an AC magnetic field superposed perpendicularly on a DC bias field. When the DC bias field is applied parallel to the wire axis, these strange phenomena are called longitudinal-field effects, while abnonnal transverse-field effects are observed when the DC bias field is perpendicular to the wire axis. In this paper, the conditions for the appearance of the abnormal transverse-field effect are investigated in detail for a superconducting Nb50%Ta ribbon. When the dimension ratios were changed, we observed a change in the magnetic behavior from the longitudinal-field to the abnormal transverse-field effect. It is suggested that such a change originates from a change in the pinning characteristics due to various motional styles of flux lines.
著者
Kim Jin-Soo Kim So-Jung Kim Ho-Gi LEE Duck-Chool UCHINO Kenji
出版者
社団法人応用物理学会
雑誌
Japanese journal of applied physics. Pt. 1, Regular papers & short notes (ISSN:00214922)
巻号頁・発行日
vol.38, no.3, pp.1433-1437, 1999-03-15
参考文献数
16
被引用文献数
16

High-power piezoelectric materials are presently being extensively developed for applications such as ultrasonic motors and piezoelectric transformers. In this study, the piezoelectric and dielectric properties of Fe_2O_3-doped 0.57Pb(Sc_<1/2>Nb_<1/2>)O_3-0.43PbTiO_3 (hereafter 0.57PSN-0.43PT), which is the morphotropic phase boundary composition of the PSN-PT system, were investigated. The maximum dielectric constant (ε_<33>/ε_0=2551) and the minimum dielectric loss (tanδ = 0.51%) at room temperature were obtained at Fe_2O_3 additions of 0.1 wt% and 0.3 wt%, respectively. The temperature dependence of the dielectric constant and the dielectric loss was measured between room temperature and 350℃. With the addition of Fe_2O_3, the piezoelectric constant d_<33> and electromechanical coupling factor k_p were slightly decreased, but the mechanical quality factor Q_m was significantly increased. The highest mechanical quality factor (Q_m = 297) was obtained at 0.3 wt% Fe_2O_3, which is 4.4 times higher than that of nondoped 0.57PSN-0.43PT ceramics. The P-E and S-E loops of the samples at room temperature and at 1.0 Hz were measured at the same time using an automated polarization measuring system.
著者
Kuh Bong Jin Choo Woong Kil Brinkman Kyle KIM Jai-Hyun DAMJANOVIC Dragan SETTER Nava
出版者
社団法人応用物理学会
雑誌
Japanese journal of applied physics. Pt. 1, Regular papers & short notes (ISSN:00214922)
巻号頁・発行日
vol.41, no.11, pp.6765-6767, 2002-11-30
参考文献数
8
被引用文献数
4

Relaxor Pb(Sc_<1/2>Nb_<1/2>)O_3 (PSN) thin films without pyrochiore phase were proccssed from the modified alkoxide solution precursors. The preparation of single phase PSN thin films has a narrow processing window due to the appearance of an undesirable pyrochlore phase and volatility of PbO. Thin film processing has been improved through selection of precursor solutions, heat treatment and optimized deposition-condition are optimized. Especially, the effects of Pt substrates seeded with additional layers upper of TiO_2 and La_<0.5>Sr_<0.5>CoO_3 are investigated through the scanning electron microscopy (SEM) scanning of filmlelectrode interfaces. Dielectric behaviors of sal-gel derived PSN thin films on two different substrates are observed. They show the evidence of relaxor-like behaviors, i.e. the temperature dependence of the dielectric constant at different applied frequencies. Films on the TiO_2/Pt/TiO_2/SiO_2/Si substrates exhibit better dielectric properties, such as frequency saturation over transition temperature and much lower dielectric loss than those on the La_<0.5>Sr_<0.5>CoO_3/Pt/TiO_2/SiO_2/Si substrates. The differences of transition behaviors between PSN thin films and bulk ceramics are also discussed in relation to the processing temperature, interface phenomena between film and electrode, relatively small thickness and strain effect of films.
著者
Nakayama Kazuya Matsuda Hideo
出版者
社団法人応用物理学会
雑誌
Japanese journal of applied physics. Pt. 1, Regular papers & short notes (ISSN:00214922)
巻号頁・発行日
vol.37, no.9, pp.4751-4757, 1998-09-15
被引用文献数
3

A new high-power (4500 V) planar metal oxide semiconductor (MOS) device is fabricated and its properties are evaluated. It has low forward voltage drop and a large reverse bias safe operating area (RBSOA), and allows easy MOS control. These properties are superior to those of the conventional insulated gate bipolar transistor (IGBT) and the gate turn-off thyristor (GTO). This is due to the conductivity modulation enhancement effect resulting from an extremely wide gate electrode, which increases the hole storage and the electron injection. At the same time, the junction field effect transistor (JFET) resistance effect does not affect the forward voltage drop. The rate of increase of the off-state voltage (dV_D/dt) during the turn-off process affects RBSOA markedly, therefore, it is important to set the gate resistance to an appropriate value. The press pack device that includes 20 chips of this device and 10 fast recovery diode chips can turn off a current of 1200 A at 3600 V DC voltage supply without a snubber circuit.
著者
Nakatani Noriyuki Hara Naoyuki
出版者
社団法人応用物理学会
雑誌
Jpn J Appl Phys (ISSN:00214922)
巻号頁・発行日
vol.32, no.7, pp.3204-3208, 1993-07-20
被引用文献数
12

Single crystals of ferroelectric triglycine sulfate (TGS) have been grown from aqueous solution containing 10 mol% of sarcosine. The crystal, referred to as SarTGS, shows a quite different habit from undoped TGS. The concentration of sarcosine incorporated in the crystal is, at most, 1/500 of the solution concentration. Although sarcosine is not chiral, an internal bias field $E_{\text{b}}$ of 40–140 kV/m is produced. The direction and intensity of $E_{\text{b}}$, as well as the domain structure, vary according to the crystal growth sector. The directions of $E_{\text{b}}$ in matching sectors in both $b$ sides of the seed crystal are opposite to each other. In the sectors where the growing surface is parallel to the $b$-axis, no bias field is produced. The cause of such a feature of $E_{\text{b}}$ in the SarTGS crystal is discussed in terms of symmetry considerations.
著者
Yamamoto Tetsuya Katayama-Yoshida Hiroshi
出版者
社団法人応用物理学会
雑誌
Japanese journal of applied physics. Pt. 2, Letters (ISSN:00214922)
巻号頁・発行日
vol.38, no.2, pp.L166-L169, 1999-02-15
被引用文献数
28 523

We have investigated the electronic structures of n- or p-type doped ZnO based on ab initio electronic band structure calculations. We find unipolarity in ZnO; n-type doping using Al, Ga or In species decreases the Madelung energy while p-type doping using N species increases the Madelung energy, in addition to causing substantial localization of the N states. Codoping using reactive codopants, Al, Ga or In, enhances the incorporation of N acceptors in p-type codoped ZnO. We find the delocalized states of N for p-type ZnO codoped with N and Al (Ga).
著者
Xiao Deng M. Liu Hong L. Qin Ling
出版者
社団法人応用物理学会
雑誌
Japanese journal of applied physics. Pt. 2, Letters (ISSN:00214922)
巻号頁・発行日
vol.38, no.8, pp.L875-L877, 1999-08-01
被引用文献数
2

The Townsend first ionization coefficient α, electron attachment coefficient η and effective ionization coefficient α^^- (=α-η) in SF_6 and xenon gas mixtures were measured by the steady-state Townsend method for 22.6 &les; E/p &les; 94 V・mm^<-1>kPa^<-1> and mixture ratios of 10:90, 25:75, 50:50, 75:25 and 90:10. The limiting E/p in SF_6-Xe, (E/p)_<lim>, which represents E/p for α/P=n/P, was derived from the pre-breakdown current growth measurements, which varies approximately linearly with SF_6 concentration in the SF_6-Xe gas mixtures.
著者
SASAKI Hitoshi IKARI Atsushi TERASHIMA Kazutaka KIMURA Shigeyuki
出版者
社団法人応用物理学会
雑誌
Japanese journal of applied physics. Pt. 1, Regular papers & short notes (ISSN:00214922)
巻号頁・発行日
vol.34, no.7, pp.3426-3431, 1995-07-15
被引用文献数
6 55 63

The temperature dependence of the electrical resistivity of molten silicon was measured based on the direct-current four-probe method in the temperature range from the melting point (1,415℃) to 1,630℃. The variation of the resistivity in this temperature region was less than 0.7%, which is much smaller than previously reported values. The measured resistivity near the solodification point was about 72×10^<-6>Ωcm, which is about 8% smaller than previously reported values. The resistivity of molten silicon showed a local minimum in the range from 1,450℃ to 1,500℃. The resistivity of molten silicon was calculated based on Ziman's formula. The temperature dependence of the measured resistivity was not reproduced when the structure factor S (Q) calculated by a simple hard-sphere model was substituted into Ziman's formula, but was reproduced by using the experimental data of S (Q) measured by Waseda which shows the first peak of asymmetric shape. This result suggests that the specific melt structure of molten silicon has a significant effect on the resistivity.
著者
Miyazaki Yuzuru Kudo Kazutaka Akoshima Megumi ONO Yasuhiro KOIKE Yoji KAJITANI Tsuyoshi
出版者
社団法人応用物理学会
雑誌
Japanese journal of applied physics. Pt. 2, Letters (ISSN:00214922)
巻号頁・発行日
vol.39, no.6, pp.L531-L533, 2000-06-01
被引用文献数
27 248

Electric resistivity, thermoelectric power and thermal conductivity of a polycrystalline sample of the composite crystal[Ca_2CoO_<3.34>]_<0.614>[CoO_2], also known as Ca_3Co_4O_9, have been measured below 300K. Metallic conductivity accompanied by large thermoelectric power has been observed down to 50K. At 300K, the sample exhibits a thermoelectric power of S = 133μV・K^<-1> resistivity of ρ = 15mΩ・cm and thermal conductivity of κ = 9.8mW・K^<-1>・cm^<-1>. The resulting dimensionless figure of merit becomes ZT_<300>=3.5×10^<-2> which is comparable to the value reported for a polycrystalline sample of NaCo_2O_4, indicating that the title compound is a potential candidate for a thermoelectric material.
著者
SAITO Yasuyuki SUGA Toru INOUE Kazuhiko MITANI Tatsuro TOMIZAWA Yutaka
出版者
社団法人応用物理学会
雑誌
Japanese journal of applied physics. Pt. 1, Regular papers & short notes (ISSN:00214922)
巻号頁・発行日
vol.30, no.9, pp.1940-1941, 1991-09-15
被引用文献数
1

We report on the drain-current (Id) Deep-level transient s-pectroscopy (DLTS) spectra of Si-implanted metal-semiconductor field effect transistors (MESFETs) with strong or weak Id low-frequency oscillations (LFOs) under the condition of high drain voltages (3 V-7 V). We found no distinguishing features directly related to the Id-LFO in these spectra having large peaks characteristic of the DLTS spectrum. These results imply that deep centers in the MESFET channel layer are not the direct origin of the Id-LFO.
著者
Miao X.S. Chong T.C. Shi L.P. TAN P.K. LI J.M. LIM K.G. QIANG W. MENG H.
出版者
社団法人応用物理学会
雑誌
Japanese journal of applied physics. Pt. 1, Regular papers & short notes (ISSN:00214922)
巻号頁・発行日
vol.41, no.3, pp.1679-1682, 2002-03-30
被引用文献数
1

The mechanism of the initialization-free phase-change optical disk was discussed. The computer simulation about the optical and thermal properties of the initialization-free disk was carried out. The results showed that Sb_2Te_3 film was a suitable additional layer of initialization-free phase-change optical disk for Ge_2Sb_<2+x>Te_5 phase-change media.
著者
HOSODA Masahiro WADA Tatsuo GARITO Anthony F. SASABE Hiroyuki
出版者
社団法人応用物理学会
雑誌
Japanese journal of applied physics. Pt. 2, Letters (ISSN:00214922)
巻号頁・発行日
vol.31, no.3, pp.L249-L251, 1992-03-01
被引用文献数
8

The third-order optical susceptibilities |x^<(3)>_<1111>(-3ω;ω,ω,ω)| for spin-coated films of free-base (H_2) and MnCl-octaethyl[18]porphyrins, and N,N',N",N&tprime;-tetramethyl-octaethyl[26]porphyrin-bistrifluoroacetate are determined by optical third-harmonic generation measurements at a wavelength of 1907 nm. The |x^<(3)>| values are 1.9 x 10^<-12>,2.6 x 10^<-12>, and 1.0 x 10^<-11> esu for H_2-[18]porphyrin, MnCl-[18]porphyrin, and [26]porphyrin, respectively. The enhancement of third-order nonlinear properties in macrocyclic compounds is discussed in terms of an extended π-electron system.
著者
AMANO Hiroshi KITO Masahiro HIRAMATSU Kazumasa AKASAKI Isamu
出版者
社団法人応用物理学会
雑誌
Japanese journal of applied physics. Pt. 2, Letters (ISSN:00214922)
巻号頁・発行日
vol.28, no.12, pp.L2112-L2114, 1989-12-20
被引用文献数
103 1589

Distinct p-type conduction is realized with Mg-doped GaN by the low-energy electron-beam irradiation (LEEBI) treatment, and the properties of the GaN p-n junction LED are reported for the first time. It was found that the LEEBI treatment drastically lowers the resistivity and remarkably enhances the PL efficiency of MOVPE-grown Mg-doped GaN. The Hall effect measurement of this Mg-doped GaN treated with LEEBI at room temperature showed that the hole concentration is 〜2・10^<16>cm^<-3>, the hole mobility is 〜8 cm^2/ V・s and the resistivity is 〜35 Ω・cm. The p-n junction LED using Mg-doped GaN treated with LEEBI as the p-type material showed strong near-band-edge emission due to the hole injection from the p-layer to the n-layer at room temperature.