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排序方式: 共有678条查询结果,搜索用时 15 毫秒
61.
Shintaro Nakano Nobuyoshi Saito Kentaro Miura Tatsunori Sakano Tomomasa Ueda Keiji Sugi Hajime Yamaguchi Isao Amemiya Masato Hiramatsu Arichika Ishida 《Journal of the Society for Information Display》2012,20(9):493-498
We have successfully reduced threshold voltage shifts of amorphous In–Ga–Zn–O thin‐film transistors (a‐IGZO TFTs) on transparent polyimide films against bias‐temperature stress below 100 mV, which is equivalent to those on glass substrates. This high reliability was achieved by dense IGZO thin films and annealing temperature below 300 °C. We have reduced bulk defects of IGZO thin films and interface defects between gate insulator and IGZO thin film by optimizing deposition conditions of IGZO thin films and annealing conditions. Furthermore, a 3.0‐in. flexible active‐matrix organic light‐emitting diode was demonstrated with the highly reliable a‐IGZO TFT backplane on polyimide film. The polyimide film coating process is compatible with mass‐production lines. We believe that flexible organic light‐emitting diode displays can be mass produced using a‐IGZO TFT backplane on polyimide films. 相似文献
62.
Phase relations in the composition range from to were studied by electrical-conductivity measurements and X-ray diffraction in the ranges and . The plot of log σ versus log showed straight lines with distinct slopes, which corresponded to four regions (, , and ). The existence of the hyperstoichiometric phase was suggested in the temperature range from 1025 to 1126°C. The peritectoid temperature () was estimated to be present between 1126 and 1131°C. The partial free enthalpies and entropies for the two-phase equilibrium (, and ) were calculated and compared with previous results. From the dependence of the electrical conductivity on the oxygen partial pressure the nonstoichiometric defect structures of and were interpreted as consisting of doubly charged oxygen interstitials (Oi'') and doubly charged oxygen vacancies (VO''). At room temperature, the homogeneity range of the U4O9 phase was investigated with a Debye-Scherrer camera. 相似文献
63.
Kanichi Kamiya Toshinobu Yoko Keiji Moroishi Kazumasa Matusita Sumio Sakka 《Journal of Materials Science》1986,21(1):131-136
The behaviour of copper ions in low thermal expansion glass-ceramics prepared from Cu2O · Al2O3 ·nSiO2 glasses, or in-spodumene type Cu2O · Ae2O3 ·nSiO2 crystals included in the glass-ceramics on heating in air was investigated. On hewing at 300 to 500° C, the copper ions behaved as in the corresponding glasses. Cuprous ions in the glass-ceramics or-spondumene type crystals were oxidized into the cupric state, and at the same time an equal amount of cuprous ions to those oxidized were expelled out of the specimen for the requirement of electrical charge neutrality and then reacted with oxygen to form CuO on the surface. The oxidation of cuprous ions and the decrease of the copper content of the-spondumene type crystals brought about a considerable decrease in the lattice spooings. 相似文献
64.
Shape identification analysis is carried out to obtain hitherto unknown defect shapes in a structure, based on the finite element and the adjoint variable methods. In this study, a test piece incorporating a known defect shape was employed to solve the shape identification problem. Also reported in this study is the shape identification problem of a cavity in a heated resin test piece made using a 3D printer by employing the temperature pattern observed on the surface of the test piece. The surface temperature of a test piece will not be uniformly distributed if it contains cavities. Practical experiments have confirmed that the characteristic of the temperature distribution depends on the size of the cavity. The thermal physical constants, i.e. the thermal conductivity and the convection coefficient, were identified for a model of the test piece incorporating a cavity based on the experimental data. Shape identification analysis was then carried out. Using numerical analysis, the finite element method was applied to simulate the temperature distribution in the test piece, and the adjoint variable method was employed to identify the cavity's shape. 相似文献
65.
We report on the recovery of population inversion in a CW-pumped erbium-doped fiber amplifier. Spontaneous emissions after the input of signal pulses were temporally resolved. The recovery time for population inversion was estimated to be a few hundred microseconds. The pump power and signal width dependences of the recovery were measured. We discuss the dependences by applying an analytical formula derived for the temporal evolution of population inversion. 相似文献
66.
Reversible and Precisely Controllable p/n‐Type Doping of MoTe2 Transistors through Electrothermal Doping 下载免费PDF全文
Yuan‐Ming Chang Shih‐Hsien Yang Che‐Yi Lin Chang‐Hung Chen Chen‐Hsin Lien Wen‐Bin Jian Keiji Ueno Yuen‐Wuu Suen Kazuhito Tsukagoshi Yen‐Fu Lin 《Advanced materials (Deerfield Beach, Fla.)》2018,30(13)
Precisely controllable and reversible p/n‐type electronic doping of molybdenum ditelluride (MoTe2) transistors is achieved by electrothermal doping (E‐doping) processes. E‐doping includes electrothermal annealing induced by an electric field in a vacuum chamber, which results in electron (n‐type) doping and exposure to air, which induces hole (p‐type) doping. The doping arises from the interaction between oxygen molecules or water vapor and defects of tellurium at the MoTe2 surface, and allows the accurate manipulation of p/n‐type electrical doping of MoTe2 transistors. Because no dopant or special gas is used in the E‐doping processes of MoTe2, E‐doping is a simple and efficient method. Moreover, through exact manipulation of p/n‐type doping of MoTe2 transistors, quasi‐complementary metal oxide semiconductor adaptive logic circuits, such as an inverter, not or gate, and not and gate, are successfully fabricated. The simple method, E‐doping, adopted in obtaining p/n‐type doping of MoTe2 transistors undoubtedly has provided an approach to create the electronic devices with desired performance. 相似文献
67.
Ino T Hayashi T Fukuda T Ueno K Shirai H 《Journal of nanoscience and nanotechnology》2011,11(9):8035-8039
Highly-conductive poly(3,4-ethylene dioxythiophene):poly(styrene sulfonic acid) (PEDOT:PSS) films obtained by the addition of dimethylsulfoxide (DMSO) and the argon plasma exposure were used as a transparent conductive anode (TCA) for copper-phthalocyanine (CuPc)/C60 organic thin-film solar cells (OSCs). The CuPc/C60 OSCs on as-grown DMSO added PEDOT:PSS layer showed a power efficiency of 0.6%, whereas it was improved markedly to 1.34% after the atmospheric-pressure argon plasma exposure, which was comparable to that formed on indium-tin-oxide layer. Effects of the DMSO addition and the argon plasma exposure in the spin-coated PEDOT:PSS films is demonstrated in terms of the in-depth characterization of optical and electrical properties. 相似文献
68.
Shiro Yamamoto Keiji Saeki Kazunari Takebayashi Yasunori Tashiro Masatoshi Kawasaki 《International Journal of Cast Metals Research》2013,26(1):1-8
The exacting quality required of hemispherical heavy-walled steel castings, used in nuclear power applications, has been remarkably improved by the adoption of a newly developed metal-mould process. This technique is dependent on the use of a metal core. The optimum conditions for solidification were determined by the finite element analytical method. The appropriate wall-thickness of the chill elements was also investigated using data based on actual experience. The core was designed in such a manner that the surface carried a series of concave “dimples” in the manner of a golf-ball, the pattern being intended to prevent the formation of cracks, generated on the casting surface when in contact with a metal mould. Stresses caused by solidification shrinkage were reduced by splitting the core. In the event, the casting structure conformed well to the results of the solidification analysis. Radiographic examination revealed a high level of soundness, with no trace of internal defects. No anisotropy was detected in mechanical properties. It is shown that this process is being currently employed in the manufacture of actual products. 相似文献
69.
Kazufumi Yogo Ryoichi Shinkuma Taku Konishi Satoko Itaya Shinichi Doi Keiji Yamada Tatsuro Takahashi 《International Journal of Network Management》2012,22(1):1-11
We have developed an incentive‐rewarding mechanism that stimulates activities in social networking services (SNSs), including content uploading and link establishment. We particularly focus on changing the reward assignment ratio based on the different risks users perceive when uploading content with different privacy settings: public‐open and friend‐limited. Learning‐based simulation allowed us to observe that SNS activity, which we measured as the amount of browsed content within a certain period, can be controlled by a rewarding assignment ratio. We then analyzed how the amount of uploaded content and the increase of established links affect SNS activity. Results suggested that the optimal reward assignment ratio to maximize SNS activity changes depending on the total amount of available reward resources. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献