Updated on 2024/04/01

写真a

 
Kobayashi Takashi
 
Organization
Graduate School of Engineering Division of Physics and Electronics Associate Professor
School of Engineering Department of Physics and Electronics
Title
Associate Professor
Affiliation
Institute of Engineering
Affiliation campus
Nakamozu Campus

Position

  • Graduate School of Engineering Division of Physics and Electronics 

    Associate Professor  2022.04 - Now

  • School of Engineering Department of Physics and Electronics 

    Associate Professor  2022.04 - Now

Degree

  • 博士（理学） （ Others ）

Research Areas

  • Manufacturing Technology (Mechanical Engineering, Electrical and Electronic Engineering, Chemical Engineering) / Electric and electronic materials

  • Manufacturing Technology (Mechanical Engineering, Electrical and Electronic Engineering, Chemical Engineering) / Electron device and electronic equipment

  • Natural Science / Semiconductors, optical properties of condensed matter and atomic physics

Research Interests

  • 有機半導体

  • デバイス物理

  • 光物理

  • 有機エレクトロニクス

Research subject summary

  • 有機半導体の光物性の解明

  • 有機電子デバイスの動作機構の解明

  • 有機太陽電池の開発および評価

Research Career

  • 有機デバイスの動作機構の解明

    有機太陽電池、変調分光、超高速分光 

  • 有機材料を用いたデバイス開発

    ポリチオフェン、ポリフルオレン、有機EL、有機トランジスタ、有機太陽電池 

  • π共役系高分子の光物性

    非線形分光、構造制御、共重合化 

Professional Memberships

  • 応用物理学会

    2001.04 - Now   Domestic

  • 応用物理学会有機分子バイオエレクトロニクス分科会

    2009.04 - Now   Domestic

  • 有機EL討論会

    2017.04 - Now   Domestic

  • 応用物理学会

Committee Memberships (off-campus)

  • 会計幹事   応用物理学会有機分子バイオエレクトロニクス分科会  

    2013.04 - 2015.03 

  • 監査   応用物理学会関西支部  

    2022.04 - Now 

  • 庶務幹事   応用物理学会関西支部  

    2015.04 - 2017.04 

  • 会計幹事   応用物理学会　有機ナノ界面制御素子研究会  

    2017.04 - Now 

  • プログラム委員   有機EL討論会  

    2017.04 - Now 

  • プログラム副委員長   有機EL討論会  

    2020.04 - 2021.03 

  • プログラム委員長   有機EL討論会  

    2021.04 - 2022.03 

▼display all

Job Career (off-campus)

  • Osaka Prefecture University   Graduate School of Engineering

    2004.04 - Now

  • 理化学研究所　基礎科学特別研究員

    2001.04 - 2004.03

Papers

  • Low Voltage Operation of Organic Phototransistor Memory with Organic Charge Storage Layer

    R. Hattori, T. Nagase, N. Nishida, T. Kobayashi, H. Naito

    Proceedings of the International Display Workshops   28   945 - 947   2021.12

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    Kind of work：Joint Work  

  • Organic Floating-Gate Memory for Image Sensing

    R. Hattori, T. Nagase, N. Nishida, T. Kobayashi, H. Naito

    Proceedings of the International Conference on Advanced Imaging   2021   42 - 45   2021.10

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    Kind of work：Joint Work  

  • Performance Improvement of Solution-Processed Organic Floating-Gate Transistor Memories via Tuning the Work Function of Gate Electrodes

    N. Nishida, R. Hattori, S. Tazuhara, M. Higashinakaya, T. Nagase, T. Kobayashi, H. Naito

    Proceedings of the 28th International Workshop on Active-Matrix Flatpanel Displays and Devices   120 - 121   2021.06

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    Kind of work：Joint Work  

  • Understanding the influence of contact resistances on short-channel high-mobility organic transistors in linear and saturation regimes Reviewed

    Shion Tazuhara, Takashi Nagase, Takashi Kobayashi, Yuichi Sadamitsu and Hiroyoshi Naito

    Appl. Phys. Express   14   2021.04

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    Kind of work：Joint Work  

  • Enhanced performance of solution-processable floating-gate organic phototransistor memory for organic image sensor applications Reviewed

    Hayato Abe, Reitaro Hattori, Takashi Nagase, Miho Higashinakaya, Shion Tazuhara, Fumiya Shiono, Takashi Kobayashi, Hiroyoshi Naito

    Applied Physics Express   14 ( 4 )   2021.04（ ISSN:1882-0778 ） （ eISSN:1882-0786 ）

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    Publishing type：Research paper (scientific journal)  

    This paper reports on the memory characteristics of solution-processed organic phototransistors (OPTs) based on poly(3-hexylthiophene) with organic semiconductor floating gates and their application to image sensors. The addition of a small amount of soluble fullerene to the floating-gate layer enhances the erasing characteristics, which helps increase the on- and off-current ratio of the OPT memories. Furthermore, the OPT memories can achieve a long extrapolated retention time (>109 s) and high photosensitivity upon illumination of as weak as 10 μW cm2. A black and white pattern printed on paper can be imaged using the solution-processed OPT memory array.

    DOI： 10.35848/1882-0786/abee9e

  • Electrically programmable multilevel nonvolatile memories based on solution-processed organic floating-gate transistors Reviewed

    M. Higashinakaya, T. Nagase, H. Abe, R. Hattori, S. Tazuhara, T. Kobayashi, H. Naito

    Applied Physics Letters   118   103301/1 - 103301/6   2021.03

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    Publishing type：Research paper (scientific journal)  

  • Revisiting open-circuit photovoltage decay in organic solar cells for the determination of bimolecular recombination constants Reviewed

    Emi Nakatsuka, Kiyohito Mori, Naoki Ueno, Takashi Kobayashi, Takashi Nagase, Hiroyoshi Naito

    Japanese Journal of Applied Physics   60 ( 3 )   2021.03（ ISSN:0021-4922 ） （ eISSN:1347-4065 ）

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    Publishing type：Research paper (scientific journal)  

    Open-circuit photovoltage decay from the steady state for the determination of bimolecular recombination constants has been studied in organic solar cells (OSCs) with three prototypical bulk heterojunctions including fullerene and non-fullerene acceptors. A simple theory for the determination of recombination constants from the initial decay rate of the open-circuit photovoltage was shown. The effective lifetimes were experimentally determined from the initial decay rates and were proportional to the −0.5 power of the excitation light intensity, indicating that the recombination process under the open-circuit condition in the OSCs is bimolecular. The experimental setup was also simple, and hence the experiment and the analysis are applicable to a variety of OSCs under operation. Information on the transport properties including bimolecular recombination constants is useful for the design and the optimization of the device architecture of OSCs.

    DOI： 10.35848/1347-4065/abdf15

  • Characterization of Electronic Transport Properties of Polymer Light-Emitting Diodes (PLEDs) by Impedance Spectroscopy

    FUJIMOTO Naoki, TAKADA Makoto, NAGASE Takashi, KOBAYASHI Takashi, NAITO Hiroyoshi

    NIHON GAZO GAKKAISHI (Journal of the Imaging Society of Japan)   60 ( 2 )   112 - 119   2021（ ISSN:1344-4425 ）

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    <p>Polymer light-emitting diodes (PLEDs) with four different emissive layers were fabricated. The current efficiencies of the optimized PLEDs with Spiro-Red (SR), Super Orange (SO), Spiro-Green (SG) and Super Yellow (SY), are 1.23, 4.33, 7.70, and 11.2cd/A, respectively. Electron and hole drift mobilities (<i>μ</i><sub>n</sub>, (<i>μ</i><sub>p</sub>), bimolecular recombination constants (<i>β</i>) of the emissive layers in working PLEDs were determined simultaneously using impedance spectroscopy (IS). The bimolecular recombination constants obtained by the IS measurement were found to be two orders of magnitude smaller than the Langevin recombination constants estimated from electron and hole drift mobilities. It is found that there is correlation between the quantum efficiency estimated from the bimolecular recombination constants and the external quantum efficiency of PLEDs.</p>

    DOI： 10.11370/isj.60.112

    CiNii Article

  • Enhancement of Optical Memory Characteristics of Solution-Processed Organic Transistor Memories with Polymer-Small-Molecule Composite Charge Storage Layers

    R. Hattori, T. Nagase, M. Higashinakaya, S. Tazuhara, T. Kobayashi, H. Naito

    Proceedings of the International Display Workshops   27   178 - 179   2020.12

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    Publishing type：Research paper (international conference proceedings)  

  • Organic Floating-Gate Transistors with Hole Trapping Characteristics for NAND-Like Memory Operation

    M. Higashinakaya, T. Nagase, R. Hattori, S. Tazuhara, T. Kobayashi, H. Naito

    Proceedings of the International Display Workshops   27   882 - 883   2020.12

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    Publishing type：Research paper (international conference proceedings)  

  • Operation mechanism and efficiency-limiting factors in solution-processed quantum-dots light-emitting diodes Reviewed

    Shoichi Sano, Takashi Nagase, Takashi Kobayashi, Hiroyoshi Naito

    Organic Electronics   86   2020.11（ ISSN:1566-1199 ）

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    Publishing type：Research paper (scientific journal)  

    Efficiency limiting factors of quantum dots light-emitting diodes (QLEDs) are studied by means of a machine learning approach using features taken from published data. Prototypical structure of QLEDs studied here is transparent conductive oxide (TCO) (anode)/hole injection layer (HIL)/hole transport layer (HTL)/quantum dots (QDs)/electron transport layer (ETL)/Al (cathode), which can be fabricated by printing processes. The most important efficiency limiting factor manifested from the machine learning is the hole injection barrier from HTL to QD layer, and the energy barrier reported in literature is about 1 eV in CdSe QDs based QLEDs. A mechanism of the hole injection in such QLEDs is examined by means of device simulation. Other efficiency limiting factors - the electron mobility of HTL and carrier balance in QD layer - are shown on the basis of the device simulation results. The importance of the efficiency limiting factors are experimentally confirmed, indicating that information concerning the electronic transport properties of HTL, QD layer and ETL is essential for the design of QLEDs by means of machine learning approach.

    DOI： 10.1016/j.orgel.2020.105865

  • Interpretation of the modulus spectra of organic field-effect transistors with electrode overlap and peripheral regions: Determination of the electronic properties of the gate insulator and organic semiconductor Reviewed

    Yu Suenaga, Miho Higashinakaya, Takashi Nagase, Takashi Kobayashi, Hiroyoshi Naito

    Japanese Journal of Applied Physics   59 ( 9 )   2020.09（ ISSN:0021-4922 ） （ eISSN:1347-4065 ）

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    Publishing type：Research paper (scientific journal)  

    The modulus spectra of organic field-effect transistors (OFETs) with electrode overlap and peripheral regions have been experimentally and theoretically investigated. The complex impedance of regioregular poly(3-hexylthiophene-2,5-diyl) (P3HT) OFETs with electrode overlap and peripheral regions was measured with a frequency response analyzer. The complex modulus was derived from an equivalent circuit of OFETs with overlap and peripheral regions using a four-terminal matrix approach. The modulus spectra of the P3HT OFETs were successfully fitted by those calculated using the expression derived from the equivalent circuit. Three structures were found in the modulus spectra of the P3HT OFETs owing to the dielectric properties of the gate insulator, transport properties of the organic semiconductor, and contact resistance from the low to high frequency ranges. The resistivity of the gate insulators and the field-effect mobility of working OFETs were determined using the values of the circuit components of the equivalent circuit obtained by fitting.

    DOI： 10.35848/1347-4065/ababb9

  • Modulated photocurrent spectroscopy study of the electronic transport properties of working organic photovoltaics: Degradation analysis Reviewed

    Emi Nakatsuka, Yo Kumoda, Kiyohito Mori, Takashi Kobayashi, Takashi Nagase, Hiroyoshi Naito

    Materials   13 ( 11 )   2020.06（ eISSN:1996-1944 ）

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    Publishing type：Research paper (scientific journal)  

    Electronic transport measurement using modulated photocurrent (MPC) spectroscopy is demonstrated herein in working organic photovoltaics (OPVs) before and after AM1.5G irradiation. OPVs with bulk heterojunction (BHJ) using prototypical donor and acceptor materials, poly[4,8-bis[(2-ethylhexyl)oxy]benzo[1-2-b:4,5-b0]dithiophene-2,6-diyl][3-fluoro-2-[(2-ethylhexyl) carbonyl] = hieno [3-4-b]thiophenediyl] (PTB7) and [6,6]-phenyl-C71-butyric acid methyl ester (PC BM), were fabricated. The OPVs had inverted structures (BHJs are formed on transparent conductive oxide substrates). The photovoltaic performance of PTB7:PC BMOPVs was characterized and the best power conversion efficiency was obtained at PTB7 content of 40 wt%. Electron and hole mobility were determined with MPC spectroscopy in PTB7:PC BM OPVs and were well balanced at PTB7 content of 40 wt%. Degradation of the photovoltaic performance of PTB7:PC BM OPVs with PTB7 content of 40 wt% caused by AM1.5G irradiation was studied. MPC spectroscopy showed that the well-balanced mobility was not affected by AM1.5G irradiation. The degradation of OPVs was not due to changes in the electronic transport properties, but mainly to the reduced short circuit current (J ) and fill factor (FF). The origin of this reduction is discussed. 71 71 71 71 sc

    DOI： 10.3390/ma13112660

  • Simultaneous determination of electron and hole drift mobilities in working inverted organic solar cells: modulated photocurrent spectroscopy versus impedance spectroscopy Reviewed

    Yo Kumoda, Emi Nakatsuka, Kiyohito Mori, Hiroki Nojima, Takashi Kobayashi, Takashi Nagase, Hiroyoshi Naito

    59   064002/1 - 6   2020.06

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    Kind of work：Joint Work  

  • Intersystem Crossing Rate in Thermally Activated Delayed Fluorescence Emitters Reviewed

    Takashi Kobayashi, Daisuke Kawate, Akitsugu Niwa, Takashi Nagase, Kenichi Goushi, Chihaya Adachi, Hiroyoshi Naito

    Physica Status Solidi (A) Applications and Materials Science   217 ( 3 )   1900616/1 - 1900616/6   2020.02（ ISSN:1862-6300 ） （ eISSN:1862-6319 ）

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    Publishing type：Research paper (scientific journal)  

    © 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim For a better understanding of the exciton decay process in thermally activated delayed fluorescence (TADF) emitters, the intersystem crossing rate, kISC, is one of the important physical constants that have to be determined. Herein, a method to calculate the kISC value from photoluminescence (PL) measurements is reconsidered. The kISC value can be determined at very low temperatures where delayed fluorescence (DF) is completely suppressed, as well as around room temperature where triplet excitons mainly decay into the ground state by emitting DF. However, there is a temperature range where the kISC value cannot be determined accurately because the influences of nonradiative decay paths can be neither ignored nor corrected. For such a temperature range, an alternative approach, which utilizes the temperature dependence of an observed PL decay rate, is presented. In this way, kISC values from 300 to 10 K are determined for thin films of two TADF emitters, i.e., 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene and 1,2-bis(carbazol-9-yl)-4,5-dicyanobenzene, which are known as 4CzIPN and 2CzPN, respectively.

    DOI： 10.1002/pssa.201900616

  • Interpretation of modulus spectra in organic field-effect transistors: Equivalent-circuit approach Reviewed

    Yu Suenaga, Takashi Nagase, Takashi Kobayashi, Hiroyoshi Naito

    Japanese Journal of Applied Physics   59 ( SD )   SDDA06/1 - SDDA06/5   2020.01（ ISSN:0021-4922 ） （ eISSN:1347-4065 ）

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    Publishing type：Research paper (scientific journal)  

    © 2019 The Japan Society of Applied Physics. Complex modulus spectra of organic field-effect transistors (OFETs) with electrode overlap regions were investigated both experimentally and theoretically. Complex modulus spectra in a poly(3-hexylthiophene-2,5-diyl) (P3HT) FET were measured using an impedance analyzer. An equivalent-circuit of OFETs with the overlap between gate and source/drain electrodes was proposed to interpret the experimentally-obtained complex modulus spectra. The complex modulus spectra calculated from the equivalent circuit were successfully fitted to the experimentally-obtained spectra of P3HT FETs. It is shown that the dielectric properties of the gate insulator, the field-effect mobility of the organic semiconductor, and the contact resistance are obtained by means of the fitting of the theoretically-obtained modulus spectra to the experimentally-obtained spectra.

    DOI： 10.7567/1347-4065/ab4ee0

  • Equivalent Circuit of Organic Field-effect Transistors with Interface States Reviewed

    Journal of the Imaging Society of Japan   59 ( 1 )   18 - 27   2020（ ISSN:1344-4425 ）

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  • Modulated Photocurrent Spectroscopy for Determination of Electron and Hole Mobilities in Working Organic Solar Cells Reviewed

    Hiroki Nojima, Takashi Kobayashi, Takashi Nagase, Hiroyoshi Naito

    Scientific Reports   9 ( 1 )   20346/1 - 20346/8   2019.12（ eISSN:2045-2322 ）

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    Publishing type：Research paper (scientific journal)  

    © 2019, The Author(s). Carrier drift mobility is an important physical constant in the charge transport process of organic solar cells (OSCs). Although time-of-flight and space-charge-limited current techniques have been frequently utilized for mobility measurements, the validity of a new method using modulation photocurrent spectroscopy is discussed in this contribution. The advantages of this method are its applicability to working OSCs with optimized device structures and the simultaneous determination of the electron and hole mobilities. These features make it possible to study the relation between the mobility balance and the solar cell characteristics, such as the power conversion efficiency, using only a single working OSC; hence, it is not necessary to fabricate electron-only and hole-only devices for mobility measurements. After carrying out numerical simulations to examine the validity of this method for mobility determination, the dependence of the mobility balance on the mixing ratio of the electron-donor and –acceptor materials is presented.

    DOI： 10.1038/s41598-019-56945-3

    PubMed

  • Mechanisms of operation in quantum-dot light-emitting diodes

    Shoichi Sano, Takashi Nagase, Takashi Kobayashi, Hiroyoshi Naito

    Proceedings of the International Display Workshops   26   947 - 948   2019.12（ ISSN:1883-2490 ） （ ISBN:9781713806301 ）

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    Publishing type：Research paper (international conference proceedings)  

    Mechanisms of operation in quantum-dot light-emitting diodes (QLEDs) have been investigated theoretically and experimentally. Important factors governing the current efficiency of QLED were examined using a machine learning approach. High hole injection barrier to QD is the dominant efficiency limiting factor, and the machine learning result was confirmed experimentally. A mechanism of high current efficiency even in the presence of high hole injection was discussed in terms of device simulation.

  • Effect of non-chlorinated solvents on the enhancement of field-effect mobility in dioctylbenzothienobenzothiophene-based top-gate organic transistors processed by spin coating Reviewed

    Shoya Sanda, Ryousuke Nakamichi, Takashi Nagase, Takashi Kobayashi, Kazuo Takimiya, Yuichi Sadamitsu, Hiroyoshi Naito

    Organic Electronics   69   181 - 189   2019.06（ ISSN:1566-1199 ）

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    Publishing type：Research paper (scientific journal)  

    © 2019 Elsevier B.V. The use of non-chlorinated solvents for film deposition in organic field-effect transistors (OFETs) is highly desirable to fabricate flexible and printable electronic circuits by environmentally friendly processes. Here, we investigate the influence of the use of non-chlorinated solvents, such as toluene, p-xylene, cyclohexanone, and mesitylene, for the deposition of 2,7-dioctyl[1]benzothieno[3,2-b][1]benzothiophene (C8-BTBT) films by spin coating on the morphologies of these semiconductor films and the electrical characteristics of OFETs with a top-gate configuration. The results show that the size of polycrystalline domains in spin-coated C8-BTBT films tends to increase as the boiling point (b.p.) of the solvent increases, whereas an improvement in the field-effect mobility is restricted by the decrease in the extent to which the C8-BTBT film covers the substrate due to the long evaporation time of high b.p. solvents. The addition of the high b.p. solvent p-xylene to toluene allows a significant increase in polycrystalline domain sizes in spin-coated C8-BTBT films. Further, spin coating C8-BTBT using the high b.p. solvent mesitylene at a high spin rate is effective for the production of thinner C8-BTBT films with diminished surface roughness. Top-gate C8-BTBT FETs processed by spin coating using a mixed binary solvent and by high-speed spin coating achieved high average field-effect mobilities of 4.9 and 5.4 cm2 V−1 s−1, respectively.

    DOI： 10.1016/j.orgel.2019.02.004

  • Modulated photocurrent spectroscopies for characterization of the charge transport process in organic photovoltaics Reviewed

    Hiroki Nojima, Takashi Kobayashi, Takashi Nagase, Hiroyoshi Naito

    Journal of Physics: Conference Series   1220 ( 1 )   012018/1 - 012018/4   2019.05（ ISSN:1742-6588 ） （ eISSN:1742-6596 ）

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    Publishing type：Research paper (international conference proceedings)  

    © Published under licence by IOP Publishing Ltd. Modified modulation photocurrent (MPC) measurements were carried out to investigate the carrier transport process in organic photovoltaics based on polymer and fullerene derivatives. In conventional MPC measurements, a photocurrent component modulating at the same frequency as the modulated incident light is recorded; however, in this study, a component modulating at twice the modulation frequency was detected. A linear process does not contribute to the detected signals; thus, this technique allows for focus on a process that converts incident photons into photocurrent in a nonlinear manner. An analysis using rate equations suggested that the nonlinearity resulted from the carrier density dependence of the internal electric field, which is the driving force of the carriers under the short-circuit condition. Furthermore, features due to both electron and hole transports were more clearly observed in the modified MPC measurements than in the conventional MPC measurements.

    DOI： 10.1088/1742-6596/1220/1/012018

  • Characterization of carrier transport properties in working polymer light-emitting diodes

    Makoto Takada, Takashi Nagase, Takashi Kobayashi, Hiroyoshi Naito

    Digest of Technical Papers - SID International Symposium   50 ( Book 1 )   263 - 266   2019.05（ ISSN:0097-966X ） （ eISSN:2168-0159 ）

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    Publishing type：Research paper (conference, symposium, etc.)  

    © 2019 SID. Charge carrier transport properties of polymer semiconductors (electron and hole drift mobilities, localized-tail-state distributions, and bimolecular recombination constants) in working polymer light-emitting diodes (PLEDs) are determined simultaneously using impedance spectroscopy (IS). The IS technique is also applicable to degradation analysis of the PLED.

    DOI： 10.1002/sdtp.12906

  • Optical memory characteristics of solution-processed organic transistors with self-organized organic floating gates for printable multi-level storage devices Reviewed

    Fumiya Shiono, Hayato Abe, Takashi Nagase, Takashi Kobayashi, Hiroyoshi Naito

    Organic Electronics   67   109 - 115   2019.04（ ISSN:1566-1199 ）

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    Publishing type：Research paper (scientific journal)  

    © 2019 Elsevier B.V. Exploring optical memory functions in nonvolatile organic field-effect transistor (OFET) memories with top-gate/bottom-contact (TG/BC) configurations can offer effective routes for developing printable, high-density organic memory circuits capable of multi-level data storage. Here, we use a solution process to fabricate TG/BC OFET devices with organic floating-gate structures and investigate their memory characteristics under light illumination. A solution-processable organic composite of 6,13-bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene) and poly(methylmethacrylate) is employed to self-organize organic floating-gate structures on a solution-processed semiconductor layer composed of poly(3-hexylthiophene) (P3HT). The floating-gate OFET devices programmed with blue, green, and red light exhibit large threshold voltage (Vth) shifts of approximately 30 V and stable charge retention characteristics even under light illumination. The devices also exhibit high sensitivity to incident light during programming, and the degree of Vth shift and the on-state current can be tuned using light and programming voltage to facilitate distinct storage and readout of multi-level data.

    DOI： 10.1016/j.orgel.2019.01.009

  • Determination of bimolecular recombination constants in organic double-injection devices using impedance spectroscopy Reviewed

    Makoto Takada, Takahiro Mayumi, Takashi Nagase, Takashi Kobayashi, Hiroyoshi Naito

    Applied Physics Letters   114 ( 12 )   123301/1 - 123301/5   2019.03（ ISSN:0003-6951 ）

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    Publishing type：Research paper (scientific journal)  

    © 2019 Author(s). A method for determination of the bimolecular recombination constant in working double-injection diodes such as organic light-emitting diodes (OLEDs) and organic photovoltaics (OPVs) using impedance spectroscopy is proposed. The proposed method is based on the theory that was developed to interpret the negative capacitance that has previously been observed in both OLEDs and OPVs. The determination of the bimolecular recombination constants is demonstrated using working polymer light-emitting diodes based on poly(9,9-dioctylfluorene-alt-benzothiadiazole). These impedance spectroscopy measurements thus allow us to 8determine the required bimolecular recombination coefficients along with the electron and hole drift mobilities in working organic double-injection diodes.

    DOI： 10.1063/1.5066605

  • Synthesis and Characterization of Soluble Directly 2,2′-Linked Tetracene Dimer Reviewed

    Tasuku Honda, Masaya Nagahara, Naohiro Taka, Jun ichi Nishida, Takeshi Kawase, Katsuhiko Ono, Takashi Kobayashi, Hiroyoshi Naito, Chitoshi Kitamura

    European Journal of Organic Chemistry   2019   2107 - 2114   2019.03（ ISSN:1434-193X ）

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    © 2019 WILEY-VCH Verlag GmbH &amp; Co. KGaA, Weinheim A soluble directly 2,2′-linked tetracene dimer was synthesized. Dimerization of 8-bromo-2,3-dihexyl-5,12-tetracenequinone afforded the corresponding bitetracenequinone, which was converted into a tetracene dimer by sequential addition of 1-hexynyllithium and SnCl 2 /HCl. The synthesized tetracene dimer with four hexyl and four 1-hexynyl groups was highly soluble in CH 2 Cl 2 and THF, and the solutions were unstable under air and room light. The compound was studied by X-ray single crystal analysis, UV/Vis, and fluorescence spectroscopy, cyclic voltammetry, and density functional theory (DFT) calculations. In the crystal, two tetracene rings take a coplanar conformation although DFT calculations demonstrated that such a molecular structure is energetically unfavorable. The tetracene dimer had red-shifted absorption maxima and large molar extinction coefficients compared with the corresponding tetracene monomer. The tetracene dimer also showed amphoteric redox properties and p-type semiconducting behavior.

    DOI： 10.1002/ejoc.201801333

  • Full characterization of electronic transport properties in working polymer light-emitting diodes via impedance spectroscopy Reviewed

    Makoto Takada, Takashi Nagase, Takashi Kobayashi, Hiroyoshi Naito

    Journal of Applied Physics   125 ( 11 )   115501/1 - 115501/9   2019.03（ ISSN:0021-8979 ） （ eISSN:1089-7550 ）

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    Publishing type：Research paper (scientific journal)  

    © 2019 Author(s). The electron and hole drift mobilities of organic semiconductor layers, localized tail state distributions, and bimolecular recombination constants in working polymer light-emitting diodes (PLEDs) are determined simultaneously using impedance spectroscopy (IS). The organic light-emitting layers of these PLEDs are composed of poly(9,9-dioctylfluorene-alt-benzothiadiazole). Electron and hole transit time effects are observed in the capacitance-frequency characteristics of the PLEDs, and their drift mobilities are determined over wide temperature and electric field ranges. The drift mobilities exhibit thermally activated behavior, and the localized tail state distributions from the conduction band and valence band mobility edges are then determined from analysis of the electric field dependences of the activation energies. The bimolecular recombination constants are determined from the inductive response of the impedance-frequency characteristics. The IS technique is also applicable to degradation analysis of the PLEDs; changes in the mobility balance, the localized tail state distributions, and the bimolecular recombination constant caused by aging are all shown.

    DOI： 10.1063/1.5085389

  • Photoinduced changes in electronic transport properties of PTB7:PC<sub>71</sub>BM inverted organic photovoltaics

    Kumoda Yo, Kobayashi Takashi, Nagase Takashi, Naito Hiroyoshi

    JSAP Annual Meetings Extended Abstracts   2019.1   2492 - 2492   2019.02（ eISSN:2436-7613 ）

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  • Effect of non-chlorinated solvents on the enhancement of field-effect mobility in dioctylbenzothienobenzothiophene-based top-gate organic transistors processed by spin coating Reviewed

    S. Sanda, R. Nakamichi, T. Nagase, T. Kobayashi, K. Takimiya, Y. Sadamitsu, H. Naito

    Organic Electronics 雑誌   69   181 - 189   2019.02

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    Kind of work：Joint Work  

  • Interfacial charges and electroluminescence in bilayer organic light-emitting diodes with different hole transport materials Reviewed

    Shuri Sato, Makoto Takada, Daisuke Kawate, Masashi Takata, Takashi Kobayashi, Hiroyoshi Naito

    Japanese Journal of Applied Physics   58   SFFA012/1 - SFFA012/5   2019.01（ ISSN:0021-4922 ）

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    Publishing type：Research paper (scientific journal)  

    © 2019 The Japan Society of Applied Physics. The performance of organic light-emitting diodes (OLEDs) and their interfacial charge density have been studied in tris-(8-hydroxyquinolate) aluminum (Alq3)-based OLEDs with four different hole transport layers (HTLs). The four HTLs have almost identical highest occupied molecular orbital (HOMO) energy levels. The performance of the four OLEDs is not greatly changed. The interfacial charge density is determined from the hole injection voltage in the capacitance - voltage characteristics of the OLEDs. Determination of the interfacial charge density is verified by device simulation. The interfacial charge density is dependent on the HTL materials in Alq3-based OLEDs, and is proportional to the difference in dipole moments between the HTLs and electron transport layers including Alq3

    DOI： 10.7567/1347-4065/ab0de7

  • Optical memory characteristics of solution-processed organic transistors with self-organized organic floating gates for printable multi-level storage devices Reviewed

    F. Shiono, H. Abe, T. Nagase, T. Kobayashi, H. Naito

    Organic Electronics 雑誌   67   109 - 115   2019.01

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    Kind of work：Joint Work  

  • Temperature dependence of the intersystem crossing rate in thermally activated delayed fluorescence emitters

    Takashi Kobayashi, Daisuke Kawase, Akitsugu Niwa, Atsumi Kayamyo, Takashi Nagase, Kenichi Goushi, Chihaya Adachi, Hiroyoshi Naito

    2019 COMPOUND SEMICONDUCTOR WEEK (CSW)   2019

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    Publishing type：Research paper (international conference proceedings)  

  • Enhanced field-effect mobility of top-gate organic transistors with channel length of 5 μm using solution-processed MoO3 hole injection layers Reviewed

    T. Aiba, T. Nagase, T. Kobayashi, Y. Sadamitsu, H. Naito

    Proceedings of the International Display Workshops 雑誌   25   721 - 722   2018.12

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    Kind of work：Joint Work  

  • Enhanced Performance of Solution-Processable Organic Floating-Gate Transistor Memories using Binary Small Molecules Dispersed Polymer Storage Layers Reviewed

    H. Abe, T. Nagase, T. Kobayashi, H. Naito

    Proceedings of the International Display Workshops 雑誌   25   403 - 404   2018.12

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    Kind of work：Joint Work  

  • Equivalent-Circuit Approach for the Interpretation of Modulus Spectra of Organic Field-Effect Transistors Reviewed

    H. Naito, Y. Suenaga, T. Nagase, T. Kobayashi

    Proceedings of the International Display Workshops 雑誌   25   253 - 256   2018.12

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    Kind of work：Joint Work  

  • 塗布形成した三酸化モリブデン正孔注入層を用いたトップゲート有機電界効果トランジスタの移動度改善 Reviewed

    饗庭智也, 永瀬 隆, 小林隆史, 貞光雄一, 内藤裕義

    日本画像学会誌 雑誌   57   537 - 542   2018.10

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  • Influence of Substrate Modification with Dipole Monolayers on the Electrical Characteristics of Short-Channel Polymer Field-Effect Transistors Reviewed

    T. Nagase, T. Hirose, T. Kobayashi, R. Ueda, A. Otomo, H. Naito

    Applied Sciences 雑誌   8   2018.08

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    Kind of work：Joint Work  

  • Triplet-triplet annihilation in a thermally activated delayed fluorescence emitter lightly doped in a host Reviewed

    A. Niwa, S. Haseyama, T. Kobayashi, T. Nagase, K. Goushi, C. Adachi, H. Naito

    Applied Physics Letters 雑誌   113   2018.08

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    Kind of work：Joint Work  

  • Determination of Interface-State Distributions in Polymer-Based Metal-Insulator-Semiconductor Capacitors by Impedance Spectroscopy Reviewed

    H. Hatta, Y. Miyagawa, T. Nagase, T. Kobayashi, T. Hamada, S. Murakami, K. Matsukawa, H. Naito

    Applied Sciences 雑誌   8   2018.08

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  • Effective Europium Coordination Luminophores Linked with Bi-and Tridentate Carbazole Phosphine Oxides for Organic Electroluminescent Devices Reviewed

    Y. Hasegawa, S. Natori, J. Fukudome, T. Nagase, T. Kobayashi, T. Nakanishi, Y. Kitagawa, K. Fushimi, and H. Naito

    Journal of Physical Chemistry C 雑誌   122   9599 - 9605   2018.04

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    Kind of work：Joint Work  

  • High-performance didodecylbenzothienobenzothiophene-based top-gate organic transistors processed by spin coating using binary solvent mixtures Reviewed

    S. Sanda, T. Nagase, T. Kobayashi, K. Takimiya, Y. Sadamitsu, H. Naito

    Organic Electronics 雑誌   58   306 - 312   2018.04

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    Kind of work：Joint Work  

  • Emission properties of thermally activated delayed fluorescence emitters: analysis based on a four-level model considering a higher triplet excited state Reviewed

    T. Kobayashi, A. Niwa, S. Haseyama, K. Takaki, T. Nagase, K. Goushi, C. Adachi, H Naito

    Journal of Photonics for Energy 雑誌 SPIE   8   2018.02

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    Kind of work：Joint Work  

  • Solution-Processed Nonvolatile Optical Transistor Memory for Multi-Level Data Storage Devices

    F. Shiono, T. Nagase, T. Kobayashi, H. Naito

    Proceedings of the International Display Workshops 雑誌 International Display Workshops   24   1575 - 1576   2017.12

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    Kind of work：Joint Work  

  • Enhanced Mobility of Top-Gate Dialkyl BTBT Transistors by Spin Coating from Non-Halogen Sol-vents

    S. Sanda, T. Nagase, T. Kobayashi, K. Takimiya, Y. Sadamitsu, H. Naito

    Proceedings of the International Display Workshops 雑誌 International Display Workshops   24   371 - 372   2017.12

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    Kind of work：Joint Work  

  • Solution-processed organic field-effect transistors based on dinaphthothienothiophene precursor with chemically modified electrodes Reviewed

    T. Nagase, S. Abe, T. Kobayashi, Y. Kimura, A. Hamaguchi, Y. Ikeda, and H. Naito

    Journal of Physics: Conference Series 雑誌 Institute of Physics   924   2017.12

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    Kind of work：Joint Work  

  • Relation between active-layer thickness and power conversion efficiency in P3HT:PCBM inverted organic photovoltaics Reviewed

    S. Nakami, T. Narioka, T. Kobayashi, T. Nagase, H. Naito

    Journal of Physics: Conference Series 雑誌 Institute of Physics   924   2017.12

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  • Electron injection in inverted organic light-emitting diodes with poly (ethyleneimine) electron injection layers Reviewed

    M Takada, T Nagase, T Kobayashi, H Naito

    Organic Electronics 雑誌 Elsevier   50   290 - 295   2017.11

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  • 異なる構造を有するポリエチレンイミンを電子注入層とした塗布型逆構造有機発光ダイオードの作製と特性評価 Reviewed

    真弓隆洋、高田 誠、森井克行、永瀬 隆、小林隆史、内藤裕義

    日本画像学会誌 雑誌 日本画像学会   56   483 - 488   2017.10

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  • Photoluminescence Properties of Polymorphic Modifications of Low Molecular Weight Poly(3-hexylthiophene) Reviewed

    T. Kobayashi, K. Kinoshita, A. Niwa, T. Nagase, H. Naito

    Nanoscale Resarch Letters 雑誌 Springer   12   2017.05

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    Kind of work：Joint Work  

  • Control of the singlet-triplet energy gap in a thermally activated delayed fluorescence emitter by using a polar host matrix Reviewed

    S. Haseyama, A. Niwa, T. Kobayashi, T. Nagase, K. Goushi, C. Adachi, H. Naito

    Nanoscale Resarch Letters 雑誌 Springer   12   2017.04

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    Kind of work：Joint Work  

  • Contributions of a higher triplet excited state to the emission properties of a thermally activated delayed-fluorescence emitter Reviewed

    T. Kobayashi, A. Niwa, K. Takaki, S. Haseyama, T. Nagase, K. Goushi, C. Adachi, H. Naito

    Physical Review Applied 雑誌 Americaln Physical Society   7   2017.03

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  • High mobility and operational stability of top-gate organic transistors based on solution-processable organic semiconductors

    T. Nagase, K. Takagi, R. Nakamichi, T. Kobayashi, H. Naito

    Proceedings of the International Display Workshops 雑誌 International Display Workshops   23   1380 - 1383   2016.12

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    Kind of work：Joint Work  

  • Organic floating-gate transistor memory based on solution-processed organic films

    F. Shiono, T. Nagase, T. Kobayashi, H. Naito

    Proceedings of the International Display Workshops 雑誌 International Display Workshops   23   1440 - 1441   2016.12

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    Kind of work：Joint Work  

  • Inverted organic light-emitting diodes with an electrochemically deposited zinc oxide electron injection layer Reviewed

    M. Takada, S. Furuta, T. Kobayashi, T. Nagase, T. Shinagawa, M. Izaki, H. Naito

    Journal of Applied Physics 雑誌 American Institute of Physics   120   2016.11

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    Kind of work：Joint Work  

  • High operational stability of solution-processed organic field-effect transistors with top-gate configuration Reviewed

    K. Takagi, T. Nagase, T. Kobayashi, H. Naito

    Organic Electronics 雑誌 Elsevier   32   64 - 69   2016.05

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    Kind of work：Joint Work  

  • Photoluminescence in a thermally activated delayed fluorescence emitter for organic light-emitting diodes Reviewed

    A. Niwa, K. Takaki, T. Kobayashi, T. Nagase, K. Goushi, C. Adachi, and H. Naito

    Journal of the Imaging Society of Japan 雑誌 The Imaging Society of Japan   55   143 - 148   2016.04

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    Kind of work：Joint Work  

  • Effects of bimolecular recombination on impedance spectra in organic semiconductors: Analytical approach Reviewed

    M. Takata, K. Takagi, T. Nagase, T. Kobayashi, H. Naito

    Journal of Nanoscience and Nanotechnology 雑誌 American Scientific Publisher   16   3322 - 3326   2016.04

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    Kind of work：Joint Work  

  • Fabrication of vertical molecular junction devices with conductive polymer contacts using a peeling method Reviewed

    Y. Konishi, T. Nagase, T. Kobayashi, R. Ueda, T. Terui, A. Otomo, H. Naito

    Journal of Nanoscience and Nanotechnology 雑誌 American Scientific Publisher   16   3307 - 3311   2016.04

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    Kind of work：Joint Work  

  • Simple Calculation of Power Conversion Efficiency of PC61BM and PC71BM Based Organic Solar Cells—Good Agreement with Experiments in Donor Materials with Different Band Gap Energies Reviewed

    T. Otsura, E. Nakatsuka, T. Nagase, T. Kobayashi, H. Naito

    Journal of Nanoscience and Nanotechnology 雑誌 American Scientific Publisher   16   3349 - 3354   2016.04

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    Kind of work：Joint Work  

  • Determination of deep trapping lifetime in organic semiconductors using impedance spectroscopy Reviewed

    K. Takagi, T. Nagase, T. Kobayashi, and H. Naito

    Appl. Phys. Lett 雑誌 American Institute of Physics   108   2016.02

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    Kind of work：Joint Work  

  • 塗布プロセスにより製膜した金属酸化物を有する有機発光ダイオードの作製 Reviewed

    高田 誠、古田 卓、小林隆史、永瀬 隆、品川 勉、伊崎昌伸、内藤裕義

    日本画像学会誌 雑誌 日本画像学会   55   3 - 8   2016.02

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    Kind of work：Joint Work  

  • Write-once memory effects observed in Ga-doped ZnO/organic semiconductor/MoO3/Au structures

    J. Hasegawa, T. Nagase, T. Kobayashi, and H. Naito

    Jpn. J. Appl. Phys. 雑誌 The Japan Society of Applied Physics   55   2016.02

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    Kind of work：Joint Work  

  • Inverted organic light-emitting diodes using different transparent conductive oxide films as a cathode

    M. Takada, T. Kobayashi, T. Nagase, and H. Naito

    Jpn. J. Appl. Phys. 雑誌 The Japan Society of Applied Physics   55   2016.02

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    Kind of work：Joint Work  

  • Effects of silica nanoparticle addition on polymer semiconductor wettability and carrier mobility in solution-processable organic transistors Reviewed

    T. Nagase, M. Yoshikawa, S. Yamazaki, T. Kobayashi, Y. Michiwaki, S. Watase, M. Watanabe, K. Matsukawa, and H. Naito

    J. Poly. Sci. Part B 雑誌 Wiley   54   509 - 516   2016.01

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  • 塗布プロセスにより作製した高性能トップゲート型有機薄膜トランジスタ

    高木謙一郎、永瀬 隆、小林隆史、内藤裕義

    電気材料技術雑誌 雑誌 電気材料技術懇談会   24   16 - 23   2015.12

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  • Control and improvement of electrical performance of solution-processable organic transistors by spin coating from mixed organic solvents

    R. Nakamichi, T. Nagase, T. Kobayashi, Y. Sadamitsu and H. Naito

    Proceedings of the 22nd International Display Workshop 雑誌 International Display Workshops   1419 - 1423   2015.12

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    Kind of work：Joint Work  

  • Fabrication of multi-layer inverted organic light emitting diodes by a spin coating method

    J. Hasegawa, M. Takada, T. Nagase, T. Kobayashi, and H. Naito

    Proceedings of the 22nd International Display Workshop 雑誌 International Display Workshops   706 - 709   2015.12

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    Kind of work：Joint Work  

  • Characterization of transport properties of organic semiconductors using impedance spectroscopy Reviewed

    K. Takagi, S. Abe, T. Nagase, T. Kobayashi, and H. Naito

    J. Mater. Sci.: Mater. Electron. 雑誌 Springer   26   4463 - 4474   2015.07

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    Kind of work：Joint Work  

  • High mobility and operational stability of polymer field-effect transistors based on a top-gate configuration

    K. Takagi, T. Nagase, T. Kobayashi, and H. Naito

    Proceedings of the 1st International Conference on Advanced Imaging 雑誌 International Conference of Advanced Imaging   217 - 220   2015.06

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    Kind of work：Joint Work  

  • Photoluminescence in a thermally activated delayed fluorescence emitter for organic light-emitting diodes

    A. Niwa, K. Takaki, T. Kobayashi, T. Nagase, K. Goushi, C. Adachi, and H. Naito

    Proceedings of the 1st International Conference on Advanced Imaging 雑誌 International Conference of Advanced Imaging   221 - 224   2015.06

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    Kind of work：Joint Work  

  • Optical properties of three differently colored crystal modifications of a 2,3-dicyanopyrazine dye Reviewed

    N. Okada, R. Eto, E. Horiguchi-Babamoto, T. Kobayashi, H. Naito, M. Shiro, H. Takahashi, and S. Matsumoto

    Bull. Chem. Soc. Jpn 雑誌 The Chemical Society of Japan   88   716 - 721   2015.05

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    Kind of work：Joint Work  

  • 非ハロゲン系溶媒を用いたベンゾチエノベンゾチオフェン有機電界効果トランジスタの高性能化 Reviewed

    中道諒介、木村 友、永瀬 隆、小林隆史、瀧宮和男、濱田雅裕、内藤裕義

    日本画像学会誌 雑誌 日本画像学会   54   109 - 114   2015.04

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    Kind of work：Joint Work  

  • High-performance and electrically stable solution-processed polymer field-effect transistors using a top-gate configuration Reviewed

    K. Takagi, T. Nagase, T. Kobayashi, T. Kushida, H. Naito

    Jpn. J. Appl. Phys 雑誌 The Japan Society of Applied Physics   54   2015.01

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    Kind of work：Joint Work  

  • Soluble Organic Semiconductor Precursor with Specific Phase Separation for High-Performance Printed Organic Transistors Reviewed

    Y. Kimura, T. Nagase, T. Kobayashi, A. Hamaguchi, Y. Ikeda, T. Shiro, K. Takimiya, H. Naito

    Adv. Mater. Wiley   27   727 - 732   2015.01

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  • High-mobility solution-processed organic field-effect transistors with channel length of 5 μm

    R. Nakamichi, T. Nagase, T. Kobayashi, Y. Sadamitsu, H. Naito

    Proceedings of the 21st International Display Workshop 雑誌 International Display Workshops   2014.12

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    Kind of work：Joint Work  

  • Stable electrical characteristics of solution processed amorphous InZnO thin-film transistors with organic passivation layers

    J. Okada, T. Nagase, T. Kobayashi, H. Naito

    Proceedings of the 21st International Display Workshop 雑誌 International Display Workshops   2014.12

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  • 塗布型有機電界効果トランジスタの移動度の温度依存性に関する一考察 Reviewed

    岡田 純、永瀬 隆、小林隆史、瀧宮和男、池田征明、内藤裕義

    日本画像学会誌 雑誌 日本画像学会   53   392 - 397   2014.10

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  • Electrical characterization of thieno[3,4-b]thiophene and benzodithiophene copolymer using field-effect transistor configuration Reviewed

    K. Takagi, T. Nagase, T. Kobayashi, and H. Naito

    Jpn. J. Appl. Phys 雑誌 The Japan Society of Applied Physics   53   2014.05

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    Kind of work：Joint Work  

  • Temperature dependence of photoluminescence properties in a thermally activated delayed fluorescence emitter Reviewed

    A. Niwa, T. Kobayashi, T. Nagase, K. Goushi, C. Adachi, and H. Naito

    Appl. Phys. Lett 雑誌 American Institute of Physics   104   2014.05

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    Kind of work：Joint Work  

  • 光誘導吸収測定による有機薄膜太陽電池の移動度評価

    小林隆史、永瀬 隆、内藤裕義

    応用物理学会 有機分子・バイオエレクトロニクス分科会会誌 雑誌 応用物理学会　有機分子・バイオエレクトロニクス分科会   25   141 - 144   2014.05

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  • Third-order optical susceptibility in polythiophene thin films prepared by spin-coating from high-boiling-point solvents Reviewed

    T. Kobayashi, W. Shinke, T. Nagase, S. Murakami, H. Naito

    Thin Solid Films 雑誌 Elsevier   554   2014.03

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  • Impedance spectroscopy for high resolution measurements of energetic distributions of localized states in organic semiconductor Reviewed

    H. Hase, T. Okachi, S. Ishihara, T. Nagase, T. Kobayashi, H. Naito

    Thin Solid Films 雑誌 Elsevier   554   2014.03

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  • Continuous-wave photoinduced absorption study on trapped carriers in bulk-heterojunction solar cells connected to load Reviewed

    Y. Terada, T. Kobayashi, E. Nakatsuka, T. Nagase, H. Naito

    Thin Solid Films 雑誌 Elsevier   554   2014.03

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  • 埋め込み電極を用いた塗布型有機電界効果トランジスタの高性能化 Reviewed

    木村 友, 永瀬 隆, 小林 隆史, 瀧宮 和男, 池田 征明, 内藤 裕義

    日本画像学会誌 雑誌 日本画像学会   53   3 - 8   2014.02

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  • Effect of contact resistance on mobility determination by impedance spectroscopy Reviewed

    M. Takata, N. Kouda, S. Ishihara, T. Nagase, T. Kobayashi, H. Naito

    Japanese Journal of Applied Physics 雑誌 The Japan Society of Applied Physics   53   2014.02

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  • High performance top-gate field-effect transistors based on poly(3-hexylthiophene) with different alkyl chain lengths Reviewed

    K. Takagi, T. Nagase, T. Kobayashi, H. Naito

    Organic Electronics 雑誌 Elsevier   15   372 - 377   2014.02

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  • Low Voltage Operation of Organic Field-Effect Transistors with Embedded Electrodes

    Y. Kimura, T. Nagase, T. Kobayashi, K. Takimiya, M. Ikeda, H. Naito

    Proceedings of the 20th International Display Workshop 雑誌 International Display Workshops   2013.12

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  • Highly oriented polymer field-effect transistors with high electrical stability Reviewed

    T. Endo, T. Nagase, T. Kobayashi, H. Naito

    Japanese Journal of Applied Physics 雑誌 The Japan Society of Applied Physics   52   2013.12

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  • Device performance of benzothienobenzothiophene-based top-gate organic field-effect transistors with embedded electrodes

    Y. Kimura, F. Mochizuki, T. Nagase, T. Kobayashi, K. Takimiya, M. Ikeda, and H. Naito

    Proceedings of the 19th International Display Workshops 雑誌 International Display Workshops   901 - 904   2012.12

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  • Effect of MoO3 hole-injection layers on the performance of top-gate organic transistors based on soluble benzothienobenzothiophene derivatives

    F. Mochizuki, Y. Miyata, T. Nagase, T. Kobayashi, K. Takimiya, M. Ikeda, and H. Naito

    Proceedings of the 19th International Display Workshops 雑誌 International Display Workshops   1129 - 1132   2012.12

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    Kind of work：Joint Work  

  • Charge transport in solution-processed top-gate organic thin-film transistors with different gate insulators

    K. Takagi, T. Nagase, T. Kobayashi, and H. Naito

    Proceedings of the 19th International Display Workshops 雑誌 International Display Workshops   905 - 908   2012.12

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  • J-aggregate structure in a chloroform solvate of a 2, 3-dicyanopyrazine dye -Separation of two-dimensional stacking dye layers by solvate formation- Reviewed

    S. Matsumoto, E. H. Babamoto, R. Eto, S. Sato, T. Kobayashi, H. Naito, M. Shiro, H. Takahashi

    dyes and pigments 雑誌 Elsevier   95   2012.11

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  • Third-order optical susceptibility of ordered and disordered polyfluorene thin films Reviewed

    T. Kobayashi, T. Endo, T. Nagasea, S. Murakami, and H. Naito

    J. Non-Crystalline Solids 雑誌 Elsevier   358   2530 - 2533   2012.09

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  • 2, 6-Dimethoxy-9, 10-anthraquinone Reviewed

    A. Ohta, K. Hattori, T. Kobayashi, H. Naito, T. Kawase, and C. Kitamura

    Acta Cryst. 雑誌 Wiley   E68   2012.09

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  • Effects of Alkoxy Substitution on the Optical Properties of 9, 10-Anthraquinone and Anthracene: 2, 3, 6, 7-Tetrapropoxy-substituted vs. 2, 6-Dipropoxy-substituted Derivatives Reviewed

    A. Ohta, K. Hattori, Y. Kusumoto, T. Kawase, T. Kobayashi, H. Naito, and C. Kitamura

    Chemistry Letters 雑誌 The Chemical Society of Japan   41   674 - 676   2012.07

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  • 2, 3, 6, 7-Tetramethoxy-9, 10-anthraquinone Reviewed

    A. Ohta, K. Hattori, T. Kawase, T. Kobayashi, H. Naito and C. Kitamura

    Acta Cryst. 雑誌 Wiley   E68   2012.07

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  • 17,17-Dialkyltetrabenzo[a,c,g,i]fluorenes with extremely high solid-state fluorescent quantum yields: Relationship between crystal structure and fluorescent properties Reviewed

    C. Kitamura, Y. Tanigawa, T. Kobayashi, H. Naito, H. Kurata, and T. Kawase

    Tetrahedron 雑誌 Elsevier   68   1688 - 1694   2012.02

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  • Determination of carrier lifetime in bulk-heterojunction solar cells by continuous-wave photoinduced absorption spectroscopy Reviewed

    T. Kobayashi, Y. Terada, T. Nagase, and H. Naito

    Appl. Phys. Express 雑誌 The Japan Society of Applied Physics   4   2011.12

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  • Enhancement of Charge Mobility in Solution-Processed Organic Field-Effect Transistors Using Top-Gate Configurations

    T. Nagase, K. Takagi, T. Kobayashi, T. Kushida, and H. Naito

    Proceedings of the 18th International Display Workshops 雑誌 International Display Workshops   125 - 128   2011.12

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  • High Hole Mobility Exceeding 4 cm2/Vs in Top-Gate C8-BTBT Field-Effect Transistors Processed by Spin Coating

    F. Mochizuki, T. Endo, T. Nagase, T. Kobayashi, K. Takimiya, M. Ikeda, and H. Naito

    Proceedings of the 18th International Display Workshops 雑誌 International Display Workshops   85 - 88   2011.12

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    Kind of work：Joint Work  

  • Frequency Characteristics of Polymer Field-Effect Transistors with Self-Aligned Electrodes Investigated by Impedance Spectroscopy Reviewed

    H. Hatta, T. Nagase, T. Kobayashi, M. Watanabe, K. Matsukawa, S. Murakami, and H. Naito

    IEICE Transactions on Electronics 雑誌 IEICE   E94-C   2011.11

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  • 1,7-Diethyl-4,10- diisopropyltetracene Reviewed

    C. Kitamura, H. Kano, T. Kawase, T. Kobayashi, and H. Naito

    Acta Crystallographica Section 雑誌 Wiley   E67   2011.10

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  • Highly Oriented J-Aggregates of Bisazomethine Dye on Aligned Poly(tetrafluoroethylene) Surfaces Reviewed

    T. Tanaka, S. Matsumoto, T. Kobayashi, M. Satoh, and T. Aoyama

    J. Phys. Chem. C 雑誌 American Chemical Society   115   19598 - 19605   2011.09

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  • Enhancement of third-order optical susceptibility in polythiophene thin films fabricated by drop casting using anhydrous solvent Reviewed

    T. Kobayashi, T. Endo, W. Shinke, T. Nagase, S. Murakami, and H. Naito

    Jpn. J. Appl. Phys 雑誌 The Japan Society of Applied Physics   50   2011.07

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  • Synthesis and Properties of anti/syn-Regioisomeric Mixtures of Alkyl-Substituted Tetracenes Reviewed

    C. Kitamura, H. Kano, H. Tsukuda, T. Kawase, T. Kobayashi, and H. Naito

    Heterocycles 雑誌 The Japan Institute of Heterocyclic Chemistry   83   1621 - 1629   2011.07

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  • Octaalkyl tetracene-1,2,3,4,7,8,9,10-octacarboxylates: synthesis by twofold [2+2+2] cocyclization and crystallochromy Reviewed

    C. Kitamura, A. Takenaka, T. Kawase, T. Kobayashi, and H. Naito

    Chem. Commun 雑誌 Royal Society of Chemistry   47   6653 - 6655   2011.04

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    Kind of work：Joint Work  

  • Oscillatory structure in the electroabsorption spectrum of π-conjugated polymer thin films: how to identify the Franz-Keldysh oscillation Reviewed

    T. Kobayashi, T. Endo, S. Ikame, T. Nagase, S. Murakami, and H. Naito

    J. Phys. Soc. Jpn. 雑誌 Physical Society of Japan   80   2011.03

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  • Synthesis and Solid-state Optical Properties of 2,3-Dialkyl- and 2,3,8,9-Tetraakyltetracenes Reviewed

    C. Kitamura, T. Ohara, A. Yoneda, T. Kawase, T. Kobayashi, H. Naito

    Chemistry Letters 雑誌 The Chemical Society of Japan   40   58 - 59   2011.01

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  • Continuous-wave photoinduced absorption studies in polythiophene and fullerene blended thin films Reviewed

    T. Kobayashi, K. Kinoshita, T. Nagase, and H. Naito

    Physcal Review B 雑誌 American Physica Society   83   2011.01

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  • Organic-Inorganic Hybrid Materials for Flexible Thin-Film Transistors

    H. Naito, T. Nagase, M. Yoshikawa, T. Kobayashi, Y. Michiwaki, K. Matsukawa

    Proceedings of the 17th International Display Workshops 雑誌 International Display Workshops   1693 - 1696   2010.12

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  • Solution-processed dioctylbenzothienobenzothiophene-based top-gate organic transistors with high mobility, low threshold voltage, and high electrical stability Reviewed

    T. Endo, T. Nagase, T. Kobayashi, K. Takimiya, M. Ikeda, H. Naito

    Applied Physics Express 雑誌 The Japan Society of Applied Physics   3   2010.12

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  • Frequency Characteristics of Solution-Processed Organic Field-Effect Transistors with Self-Aligned Electrodes

    T. Nagase, H. Hatta, Y. Miyagawa, T. Kobayashi, S. Murakami, M. Watanabe, K. Matsukawa, and H. Naito

    Proceedings of the 17th International Display Workshops 雑誌 International Display Workshops   739 - 742   2010.12

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  • Wettability Improvement by Silica Nanoparticle Addition in Solution-Processed TIPS-Pentacene Field-Effect Transistors

    K. Matsukawa, S. Yamazaki, S. Tokai, M. Yoshikawa, T. Nagase, T. Kobayashi, Y. Michiwaki, S. Watase, M. Watanabe, and H. Naito

    Proceedings of the 17th International Display Workshops 雑誌 International Display Workshops   869 - 872   2010.12

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  • A low-temperature and highly reproducible fabrication process for high-mobility solution-processed small molecule field-effect transistors

    T. Endo, T. Nagase, T. Kobayashi, K. Takimiya, M. Ikeda, and H. Naito

    Proceedings of the 17th International Display Workshops 雑誌 International Display Workshops   2235 - 2238   2010.12

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  • Low-Temperature Processable Organic-Inorganic Hybrid Gate Dielectrics for Solution-Based Organic Field-Effect Transistors Reviewed

    T. Nagase, T. Hamada, K. Tomatsu, S. Yamazaki, T. Kobayashi, S. Murakami, K. Matsukawa, and H. Naito

    Advanced Materials 雑誌 Wiley   22   4706 - 4710   2010.11

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  • 1,4,5,8-Tetra-n-butylanthracene Reviewed

    C. Kitamura, H. Tsukuda, T. Kawase, T. Kobayashi, and H. Naito

    Acta Cryst. 雑誌 Wiley   E66   2010.09

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  • Drastic Improvement in Wettability of 6,13-Bis(triisopropylsilylethynyl)pentacene by Addition of Silica Nanoparticles for Solution-Processable Organic Field-Effect Transistors Reviewed

    S. Yamazaki, T. Hamada, T. Nagase, S. Tokai, M. Yoshikawa, T. Kobayashi, Y. Michiwaki, S. Watase, M. Watanabe, K. Matsukawa, and H. Naito

    Applied Physics Express 雑誌 The Japan Society of Applied Physics   3   2010.09

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  • Crystal Structure of 1,4,5,8-Tetrapentylanthracene Reviewed

    C. Kitamura, H. Tsukuda, T. Kawase, T. Kobayashi, and H. Naito

    Analytical Sciences: X-ray Structure Analysis Online 雑誌 The Japan Society for Analytical Chemistry   26   65 - 66   2010.09

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  • Device characteristics of short-channel polymer field-effect transistors Reviewed

    T. Hirose, T. Nagase, T. Kobayashi, R. Ueda, A. Otomo, and H. Naito

    Appl. Phys. Lett 雑誌 American Institute of Physics   97   2010.08

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  • 1,4,5,8-Tetraisopropylanthracene Reviewed

    C. Kitamura, H. Tsukuda, T. Kawase, T. Kobayashi, and H. Naito

    Acta Cryst. 雑誌 Wiley   E66   2010.08

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  • Photoinduced absorption in P3HT/PCBM bulk heterostructures Reviewed

    K. Kinoshita, T. Kobayashi, T. Nagase, and H. Naito

    Materials Science Forum 雑誌 Trans Tech Publications   658   503 - 506   2010.07

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    Kind of work：Joint Work  

  • Improvement of Wettability of Soluble Organic Semiconductors by Silica Nanoparticle Addition for Solution-Processable Organic Transistors

    S. Yamazaki, T. Hamada, S. Tokai, M. Yoshikawa, T. Nagase, T. Kobayashi, Y. Michiwaki, S. Watase, M. Watanabe, K. Matsukawa, and H. Naito

    Digest of Technical Papers of Active-Matrix Flatpanel Display and Devices 雑誌 The Japan Society of Applied Physics   2010.07

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  • 1,4,7,10-Tetraisoalkyltetracenes: Tuning of Solid-State Optical Properties and Fluorescence Quantum Yields by Peripheral Modulation Reviewed

    C. Kitamura, H. Tsukuda, A. Yoneda, T. Kawase, T. Kobayashi, and H. Naito

    Eur. J. Org. Chem. 雑誌 Wiley   13   3033 - 3040   2010.06

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  • Synthesis, Optical Properties, and Crystal Structure of 1,4-Dipropyltetracene Reviewed

    C. Kitamura, C. Matsumoto, A. Yoneda, T. Kobayashi, H. Naito, T. Komatsu

    Eur. J. Org. Chem. 雑誌 Wiley   13   2571 - 2575   2010.05

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  • High-mobility organic field-effect transistors based on soluble small molecules dispersed polymers

    S. Wakuta, H. Hatta, M. Yoshikawa, T. Nagase, T. Kobayashi, M. Ikeda, K. Takimiya, and H. Naito

    Proceeding of the 31st International Congress on Imaging Science 雑誌 Imaging Society of Japan   699 - 702   2010.05

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    Kind of work：Joint Work  

  • Poly (3-hexylthiophene)-based field-effect transistors with silsesquioxane gate insulators

    K. Tomatsu, T. Hamada, T. Nagase, S. Yamazaki, T. Kobayashi, S. Murakami, K. Matsukawa, and H. Naito

    Proceeding of the 31st International Congress on Imaging Science 雑誌 Imaging Society of Japan   743 - 746   2010.05

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  • Photodegradation dynamics of polyfluorene derivative studied by means of photoluminescence spectroscopy

    M. Nakagawa, T. Kobayashi, T. Nagase, and H. Naito

    Proceeding of the 31st International Congress on Imaging Science 雑誌 Imaging Society of Japan   775 - 778   2010.05

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  • Photovoltaic properties of bisazomethine dye thin films Reviewed

    T. Hosokai, T. Aoyama, T. Kobayashi, A. Nakao, S. Matsumoto

    Chemical Physics Letter 雑誌 Elsevier   487   77 - 80   2010.02

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  • Electroabsorption study of ordered polyfluorene thin films: Origin of oscillatory structure near the bottom of the continuum state Reviewed

    T. Endo, S. Ikame, T. Kobayashi, T. Nagase, S. Murakami, and H. Naito

    Physcal Review B 雑誌 American Physica Society   81   2010.01

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  • Synthesis and Crystallochromy of 1,4,7,10-Tetraalkyltetracenes: Tuning of Solid-State Optical Properties of Tetracenes by Alkyl Side-Chain Length Reviewed

    C. Kitamura, Y. Abe, T. Ohara, A. Yoneda, T. Kawase, T. Kobayashi, H. Naito, and T. Komatsu

    Chemistry A European Journal 雑誌 Wiley   16   890 - 898   2010.01

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  • Determination of Localized-State Distributions in Polyfluorene-based Light-Emitting layer by Impedance Spectroscopy

    H. Hase, T. Okachi, T. Nagase, T. Kobayashi, and H. Naito

    Proceedings of The 16th International Display Workshops 雑誌 International Display Workshops   1069 - 1072   2009.12

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  • Device Characteristics of Nanoscale Organic Field-Effect Transistors

    T. Nagase, T. Hirose, S. Nishigami, T. Kobayashi, R. Ueda, A. Otomo, and H. Naito

    Proceedings of The 16th International Display Workshops 雑誌 International Display Workshops   1785 - 1788   2009.12

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  • Preparation, Crystal Structure, and Solid-state Fluorescence of a CH2Cl2 Solvate Crystal of 6,13-Bis(t-butylphenyl)-2,3,9,10-tetrapropoxypentacene Reviewed

    C. Kitamura, T. Naito, A. Yoneda, T. Kobayashi, H. Naito, T. Komatsu

    Chemistry Letters 雑誌 The Chemical Society of Japan   38   600 - 601   2009.06

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  • Determination of localized-state distributions in organic light-emitting diodes by impedance spectroscopy Reviewed

    T. Okachi, T. Nagase, T. Kobayashi, H. Naito

    Appl. Phys. Lett 雑誌 American Institute of Physics   94   2009.01

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  • Simultaneous determination of localized-state distributions and charge-carrier mobility in organic light-emitting diodes by impedance spectroscopy

    T. Okachi, T. Nagase, T. Kobayashi, H. Naito

    Proceedings of The 15th International Display Workshops 雑誌 International Display Workshops   1021 - 1024   2008.12

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  • Chemical design of polysilsesquioxane as a gate insulator for organic thin-film transistors

    T. Hamada, S. Yamazaki, T. Nagase, K. Tomatsu, Y. Ueda, M. Watanabe, S. Watase, T. Tamai, T. Kobayashi, S. Murakami, H. Naito, K. Matsukawa

    Proceedings of The 15th International Display Workshops 雑誌 International Display Workshops   1665 - 1668   2008.12

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  • Determination of charge-carrier mobility in organic light-emitting diodes by impedance spectroscopy in presence of localized states Reviewed

    T. Okachi, T. Nagase, T. Kobayashi, H. Naito

    Jpn. J. Appl. Phys. 雑誌 The Japan Society of Applied Physics   47   8965 - 8972   2008.12

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  • Correlation between the crystallization of polyfluorene and the surface free energy of substrates Reviewed

    T. Kobayashi, H. Uda, T. Nagase, M. Watanabe, K. Matsukawa, H. Naito

    Thin Solid Fiｌｍｓ 雑誌 Elsevier   517   1340 - 1342   2008.09

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  • Anisotropic optical properties of aligned b-phase polyfluorene thin films Reviewed

    T. Endo, T. Kobayashi, T. Nagase, H. Naito

    Thin Solid Fiｌｍｓ 雑誌 Elsevier   517   1324 - 1326   2008.09

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  • Influence of injection barrier on the determination of charge-carrier mobility in organic light-emitting diodes by impedance spectroscopy Reviewed

    T. Okachi, T. Nagase, T. Kobayashi, and H. Naito

    Thin Solid Fiｌｍｓ 雑誌 Elsevier   517   1331 - 1334   2008.09

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  • Equivalent circuits of polymer light-emitting diodes with hole-injection layer studied by impedance spectroscopy Reviewed

    T. Okachi, T. Nagase, T. Kobayashi, and H. Naito

    Thin Solid Fiｌｍｓ 雑誌 Elsevier   517   1327 - 1330   2008.09

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  • Electrical characteristics of polymer field-effect transistors with poly(methylsilsesquioxane) gate dielectrics on plastic substrates Reviewed

    S. Yamazaki, T. Hamada, K. Tomatsu , Y. Ueda , T. Nagase, T. Kobayashi, S. Murakami, K. Matsukawa , H. Naito

    Thin Solid Fiｌｍｓ 雑誌 Elsevier   517   1343 - 1345   2008.09

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  • Effective Control of Surface Property on Polysilsesquioxane Films by Chemical Modification Reviewed

    T. Hamada, T. Nagase, T. Kobayashi, K. Matsukawa, and H. Naito

    Thin Solid Fiｌｍｓ 雑誌 Elsevier   517   1335 - 1339   2008.09

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  • Study on a Facile Synthesis, Crystal Structure, and the Solid-State Fluorescence of Dicyclohexane-Annelated Anthracene Reviewed

    C. Kitamura, C. Matsumoto, N. Kawatsuki, A. Yoneda, K. Asada, T. Kobayashi, and H. Naito

    Bull Chem Soc Jpn 雑誌 The Chemical Society of Japan   81   2008.06

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  • Fabrication of poly (3-hexylthiophene) field-effect transistors with poly(methylsilsesquioxane) gate dielectrics on plastic substrates

    S. Yamazaki, T. Hamada, K. Tomatsu, Y. Ueda, T. Nagase, T. Kobayashi, S. Murakami, K. Matsukawa, H. Naito

    Digest of Technical Papers of Active-Matrix Flatpanel Display and Devices 雑誌 The Japan Society of Applied Physics   149 - 152   2008.06

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  • Device characteristics in polymer field-effect transistors with poly(methyl silsesquioxane) gate insulators

    K. Tomatsu, T. Hamada, S. Yamazaki, T. Nagase, T. Kobayashi, S. Murakami, K. Matsukawa, H. Naito

    Proceedings of Pan-Pacific Imaging Conference ’08 雑誌 The Imaging Society of Japan   372 - 374   2008.06

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  • Analysis of time-of-flight transient photocurrent in organic semiconductors with coplanar-blocking-electrodes configuration Reviewed

    T. Yoshikawa, T. Nagase, T. Kobayashi, S. Murakami, and H. Naito

    Thin Solid Fiｌｍｓ 雑誌 Elsevier   516   2595 - 2599   2008.05

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  • 共役系高分子の結晶化と光学応答

    小林隆史、永瀬 隆、内藤裕義

    応用物理学会　有機分子・バイオエレクトロニクス分科会会誌 雑誌 応用物理学会　有機分子・バイオエレクトロニクス分科会   19   77 - 80   2008.05

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  • A study of a- and b-phase poly(9, 9-dioctylfluorene) by electroabsorption spectroscopy Reviewed

    T. Endo, S. Ikame, Y. Suzuki, T. Kobayashi, S. Murakami, and H. Naito

    Thin Solid Fiｌｍｓ 雑誌 Elsevier   516   2537 - 2540   2008.05

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  • Fabrication and characterization of poly(3-hexylthiophene)-based field-effect transistors with silsesquioxane gate insulators Reviewed

    K. Tomatsu, T. Hamada, T. Nagase, T. Kobayashi, S. Murakami, K. Matsukawa, and H. Naito

    Jpn. J. Appl. Phys. 雑誌 The Japan Society of Applied Physics   47   3196 - 3199   2008.04

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  • Preparation and optical properties of aligned beta-phase polyfluorene thin films Reviewed

    T. Endo, T. Kobayashi, T. Nagase, and H. Naito

    Jpn. J. Appl. Phys. 雑誌 The Japan Society of Applied Physics   46   1093 - 1095   2007.12

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  • Influence of alkyl chain length on the solid-state packing and fluorescence of 1, 4, 5, 8-Tetra(alkyl)anthracenes Reviewed

    C. Kitamura, Y. Abe, N. Kawatsuki, A. Yoneda, K. Asada, T. Kobayashi, and H. Naito

    Molecular Crystals and Liquid Crystals 雑誌 Taylor and Francis group   474   119 - 135   2007.12

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  • Optical Properties of Air-stable Semiconducting Copolymer Based on Polythiophene Reviewed

    Y. Shimizu, T. Kobayashi, T. Nagase, and H. Naito

    Appl. Phys. Lett. 雑誌 American Institute of Physics   91   2007.10

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  • Conformational Polymorphism and Optical Properties in the Solid State of 1, 4, 7, 10-Tetra(n-butyl)tetracene Reviewed

    C. Kitamura, T. Ohara, N. Kawatsuki, A. Yodeda, T. Kobayashi, H. Naito, T. Komatsu, and T. Kitamura

    CrystEngComm 雑誌 ROYAL SOC CHEMISTRY   9   644 - 647   2007.08

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  • Influence of the liquid carbazole concentration on charge trapping in C60 sensitized photorefractive polymers Reviewed

    J. C. Ribierre, T. Aoyama, T. Kobayashi, T. Sassa, T. Muto, and T. Wada

    J. Appl. Phys. 雑誌 American Institute of Physics   102   2007.08

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  • Amplified spontaneous emission in α-phase and β-phase polyfluorene waveguides Reviewed

    H. Azuma, T. Kobayashi, Y. Shim, N. Mamedov, and H. Naito

    Organic Electronics 雑誌 Elsevier   8   184 - 188   2007.04

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  • Electronic structure of a glassy poly(9,9-dioctylfluorene) thin film determined using linear and nonlinear spectroscopies Reviewed

    S. Ikame, T. Kobayashi, S. Murakami, H. Naito

    Physcal Review B 雑誌 American Physica Society   75   035209 - 1   2007.01

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  • Impedance spectroscopy and equivalent circuits of polymer light-emitting diodes

    T. Okachi, H. Azuma, T. Nagase, T. Kobayashi, H. Naito

    Proceedings of The 13th International Display Workshops 2006 雑誌 Elsevier   1323 - 1326   2006.12

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  • Optical nonlinearity of J-aggregates in vapor-deposited films of bisazomethine dye Reviewed

    T. Kobayashi, S. Matsumoto, T. Aoyama, and T. Wada

    Thin Solid Fiｌｍｓ 雑誌 Elsevier   509   145 - 148   2006.05

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  • Photoluminescence properties of facial- and meridional-Ir(ppy)3 thin films Reviewed

    N. Ide, N. Matsusue, T. Kobayashi, and H. Naito

    Thin Solid Fiｌｍｓ 雑誌 Elsevier   509   164 - 167   2006.05

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  • Fabrication of α- and β-phase poly(9,9-dioctylfluorene) thin films Reviewed

    H. Azuma, K. Asada, T. Kobayashi, and H. Naito

    Thin Solid Fiｌｍｓ 雑誌 Elsevier   509   182 - 184   2006.05

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  • Temperature dependence of photoluminescence in polyfluorene thin films - Huang-Rhys factors of as-coated, annealed and crystallized thin films - Reviewed

    K. Asada, T. Kobayashi, and H. Naito

    Thin Solid Fiｌｍｓ 雑誌 Elsevier   499   192 - 195   2006.03

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  • Crystal Structure of 5,12-Diphenyltetracene Reviewed

    C. Kitamura, C. Matsumoto, N. Kawatsuki, A. Yoneda, T. Kobayashi, and H. Naito

    Analytical Sciences: X-ray Structure Analysis Online 雑誌 The Japan Society for Analytical Chemistry   22   2006.03

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  • Control of effective conjugation length in polyfluorene thin films Reviewed

    K. Asada, T. Kobayashi, and H. Naito

    Jpn. J. Appl. Phys. 雑誌 The Japan Society of Applied Physics   45   247 - 249   2006.03

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  • Transient photocurrent of (silicon nanocrystals)-(organic polysilane) composites-detection of surface states of silicon nanocrystals Reviewed

    M. Ando, T. Kobayashi, H. Naito, T. Nagase, and Y. Kanemitsu

    Thin Solid Fiｌｍｓ 雑誌 Elsevier   499   119 - 122   2006.03

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  • Impedance spectroscopy of polymer light-emitting diodes

    H. Azuma, T. Okachi, N. Watanabe, T. Kobayashi and H. Naito

    Proceedings of The 12th International Display Workshops in conjunction with Asia Display 2005 雑誌 Elsevier   757 - 760   2005.12

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  • Spectral shape of photoluminescence in luminescent p conjugated polymers Reviewed

    T. Kobayashi, T. Endo, M. Rikukawa, K. Sanui, H. Kunugita, and K. Ema

    Synth. Metals 雑誌 Elsevier   154   129 - 132   2005.09

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  • Two-Beam Coupling Gain and Trap Density in Liquid Carbazole-Based Photorefractive Polymers Reviewed

    T. Aoyama, J.-C. Ribierre, T. Sassa, T. Kobayashi, T. Muto, and T. Wada

    Nonlinear Opt. Quant. Opt. 雑誌 Old City Publishing   34   151 - 154   2005.08

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  • Morphological characteristics of J-aggregate films of bisazomethine dyes Reviewed

    S. Matsumoto, M. Satoh, D. Tsuchida, T. Kobayashi, T. Aoyama, and T. Wada

    Trans. MRS-J 雑誌 The Materials Research Society of Japan   30   345 - 348   2005.04

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  • Temperature dependence of photoluminescence lifetime and quantum efficiency in neat Ir(ppy)3 Thin Films Reviewed

    T. Kobayashi, N. Ide, N. Matsusue, and H. Naito

    Jpn. J. Appl. Phys. 雑誌 The Japan Society of Applied Physics   44   1966 - 1969   2005.04

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  • Photoluminescence properties of vapor deposited films of a bisazomethine dye Reviewed

    T. Kobayashi, S. Matsumoto, T. Tanaka, H. Kunugita, K. Ema, T. Aoyama, and T. Wada

    Phys. Chem. Chem. Phys. 雑誌 ROYAL SOC CHEMISTRY   7   1726 - 1731   2005.04

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  • Optical properties of J-aggregates in vapor deposited films of a bisazomethine dye Reviewed

    S. Matsumoto, T. Kobayashi, T. Aoyama and T. Wada

    Trans. MRS-J 雑誌 The Materials Research Society of Japan   29   3171 - 3174   2004.11

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  • 9-(2-ethylhexyl)carbazole for carrier transport and photorefractive materials

    T. Aoyama, J. -C. Ribierre, T. Sassa, T. Kobayashi, T. Muto, and T. Wada

    Proceeding of SPIE 雑誌 SPIE   5521   2004.08

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  • J-aggregates in vapor deposited films of a bisazomethine dye Reviewed

    S. Matsumoto, T. Kobayashi, T. Aoyama, and T. Wada

    Chem. Comm. 雑誌 Royal Society of Chemistry   1910 - 1911   2003.07

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  • Coexistence of photoluminescence from two intrachain states in polythiophene films Reviewed

    T. Kobayashi, J. Hamazaki, H. Kunugita, K. Ema, T. Endo, M. Rikukawa, and K. Sanui

    Physcal Review B 雑誌 American Physica Society   67   205214 - 1   2003.05

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  • Time-resolved photoluminescence measurement on polythiophene derivative Reviewed

    T. Kobayashi, T. Wada, H. Kunugita, and K. Ema

    RIKEN Review 雑誌 RIKEN   49   47 - 51   2002.11

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  • Photoluminescence from the even-parity state in polythiophene derivative Reviewed

    T. Kobayashi, J. Hamazaki, M. Arakawa H. Kunugita, T. Endo, M. Rikukawa, K. Sanui, and K. Ema

    J. Phys. Soc. Jpn. 雑誌 Physical Society of Japan   70   2517 - 2520   2001.09

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    Kind of work：Joint Work  

  • Radiative transition from even-parity state in conjugated polymer

    T. Kobayashi, J. Hamazaki, M. Arakawa, H. Kunugita, K. Ema, K. Ochiai, M. Rikukawa, K. Sanui

    Conference on Lasers and Electro-Optics Europe - Technical Digest 雑誌 IEEE   295 - 296   2001.05

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    Kind of work：Joint Work  

  • Self-trapped exciton dynamics in highly ordered and disordered films of polythiophene derivative Reviewed

    T. Kobayashi, J. Hamazaki, M. Arakawa, H. Kunugita, K. Ema, K. Ochiai, M. Rikukawa, and K. Sanui

    Physcal Review B 雑誌 American Physica Society   62   8580 - 8583   2000.10

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    Kind of work：Joint Work  

  • Photoluminescence dynamics in polythiophene derivative

    T. Kobayashi, J. Hamazaki, M. Arakawa, H. Kunugita, K. Ema, K. Ochiai, M. Rikukawa, K. Sanui

    IQEC, International Quantum Electronics Conference Proceedings 雑誌   2000.09

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    Kind of work：Joint Work  

  • Self-trapped exciton dynamics in highly ordered and disorder films of polythiophene derivative

    T. Kobayashi, J. Hamazaki, M. Arakawa, H. Kunugita, K. Ema, K. Ochiai, M. Rikukawa, K. Sanui

    Nonlinear Optics: Materials, Fundamentals, and Applications, 2000. Technical Digest 雑誌 IEEE   377 - 379   2000.08

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    Kind of work：Joint Work  

  • Distribution of the effective conjugation length of polythiophene determined by its absorption and |c(3)| spectra Reviewed

    T. Kobayashi, J. Hamazaki, H. Kunugita, K. Ema, K. Ochiai, M. Rikukawa, and K. Sanui

    J. Nonlinear Opt. Phys. Mat. 雑誌 WORLD SCIENTIFIC PUBL CO PTE LTD   9   55 - 61   2000.03

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    Kind of work：Joint Work  

  • Spectra of |c(3)(w: w, w,- w)| at excitonic resonance in poly(3-[2-((S)-2-methylbutoxy) ethyl]thiophene) Reviewed

    S. Kishino, T. Kobayashi, H. Kunugita, K. Ema, K. Ochiai, M. Rikukawa, and K. Sanui

    Nonlinear Optics 雑誌 Gordon and Breach Science publishers   22   361 - 364   1999.09

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    Kind of work：Joint Work  

  • Estimation of effective conjugation length in Poly(3-[2-((S)-2-methylbutoxy)ethyl] thiophene) by DFWM Reviewed

    S. Kishino, Y. Ueno, K. Ochiai, M. Rikukawa, K. Sanui, T. Kobayashi, H. Kunugita, and K. Ema

    Physcal Review B 雑誌 American Physica Society   58   13430 - 13433   1998.11

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    Kind of work：Joint Work  

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Books and Other Publications

  • Organic semiconductors for optoelectronics

    （ Role： Contributor）

    John Wiley & Sons Ltd  2021  （ ISBN:9781119146100 ）

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    Total pages：xviii, 364 p.   Responsible for pages：93-136   Book type：Scholarly book

    CiNii Books

  • Optical Properties of Materials and Their Applications (2nd edition)

    T. Kobayashi, H. Naito（ Role： Contributor ,  Ch.11 "Optical Properties of Organic Semiconductors"）

    John Wiley & Sons Ltd  2020.01  （ ISBN:111950631X ）

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    Total pages：672   Responsible for pages：295-322   Book type：Scholarly book

    Edited by J. Singh

    ASIN

  • Electronic structures of planar and nonplanar polyfluorene

    T. Kobayashi, T. Nagase, H. Naito（ Role： Joint author）

    Springer  2015  （ ISBN:978-981-287-130-5 ）

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    Responsible for pages：63-80  

  • 塗布型ゲート絶縁膜の開発と塗布型有機FETの特性

    永瀬 隆, 濱田 崇, 小林隆史, 松川公洋, 内藤裕義（ Role： Joint author）

    シーエムシー出版  2012.04 

  • 有機エレクトロニクスの展開　最新開発状況と実用化への課題

    小林隆史、内藤裕義（ Role： Joint author）

    情報機構  2007.09 

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    Responsible for pages：162-171  

  • 有機エレクトロニクスにおける分子配向技術

    小林隆史、内藤裕義（ Role： Joint author）

    シーエムシー出版  2007.04 

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    Responsible for pages：73-80  

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MISC

Collaborative research (seeds) keywords

  • 熱活性化遅延蛍光材料

  • 有機太陽電池

  • π共役系高分子

  • 超高速分光

  • 非線形光学分光

Outline of collaborative research (seeds)

  • 有機デバイスの動作機構に関する研究

  • 有機材料を用いたデバイス開発

  • 有機材料の基礎物性評価

Charge of on-campus class subject

  • 電磁気学2A

    2023   Weekly class   Undergraduate

  • 有機光物理特論

    2023   Weekly class   Graduate school

  • 電子物理工学概論1

    2023   Weekly class   Undergraduate

  • 電子物理系特別演習第1（電子物性）

    2023   Intensive lecture   Graduate school

  • 電子物理工学実験1（電子物性）

    2024   Weekly class   Undergraduate

  • 電子物理工学概論1

    2024   Weekly class   Undergraduate

  • 有機光物理特論

    2024   Weekly class   Graduate school

  • 電子物理系特別研究第1（電子物性）

    2024   Intensive lecture   Graduate school

  • 電子物理系特別演習第1（電子物性）

    2024   Intensive lecture   Graduate school

  • 電子物理系特別演習（電子物性）

    2024   Intensive lecture   Graduate school

  • 電子物理系特別研究第1（電子物性）

    2023   Intensive lecture   Graduate school

  • 電子物理系特別研究第2（電子物性）

    2023   Intensive lecture   Graduate school

  • 電子物理系特別演習第2（電子物性）

    2023   Intensive lecture   Graduate school

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Faculty development activities

  • 工学FDセミナー「高等学校における学習指導要領改定に伴う情報科教育の今」  2023

Other

  • 研究職歴

    2013.04 - 2022.03

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    大阪府立大学大学院　工学研究科　電子・数物系専攻　電子物理工学分野　准教授

  • 研究職歴

    2007.04 - 2013.03

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    大阪府立大学大学院　工学研究科　電子・数物系専攻　電子物理工学分野　助教

  • 研究職歴

    2004.04 - 2007.03

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    大阪府立大学大学院　工学研究科　電子・数物系専攻　電子物理工学分野　助手