HOME > Profile > YASUDA, Takeshi
- Address
- 305-0047 1-2-1 Sengen Tsukuba Ibaraki JAPAN [Access]
Research
- Keywords
organic semiconductors, π-conjugated polymers, molecular orientation
PublicationsNIMS affiliated publications since 2004.
Research papers
- 柳生 進二郎, 吉武 道子, 長田 貴弘, 安田 剛, 桑島 功, 劉 雨彬, 中島 嘉之. 有機半導体材料における光電子収量分光(PYS)データベース構築. Journal of Surface Analysis. 29 [3] (2023) 146-154 10.1384/jsa.29.146 Open Access
- Junhui Chen, Akito Ichige, Tianyi Cai, Junpei Kuwabara, Takeshi Yasuda, Takaki Kanbara. Synthesis of a thiazole N-oxide-based π-conjugated polymer via direct arylation polycondensation under mild conditions. Polymer. 337 (2025) 129006 10.1016/j.polymer.2025.129006
- Takeshi Yasuda, Ayako Omura Okano. Quantitative determination of built-in voltage in exciplex-type two-layer organic light-emitting diodes using a simple analytic equation. Organic Electronics. 158 (2026) 107481 10.1016/j.orgel.2026.107481
Books
- 筒井 哲夫, YASUDA, Takeshi. Physics and Technology of Organic Light-Emitting Diodes. Physics and Technology of Organic Light-Emitting Diodes. Wiley, 2026, 311.
- 筒井 哲夫, 安田 剛. 有機ELのデバイス物理. 有機ELのデバイス物理. 丸善出版, 2023, 362.
- 安田 剛. アモルファス有機薄膜を用いた有機太陽電池の開発. 有機薄膜太陽電池・ペロブスカイト太陽電池の開発最前線. 株式会社エヌ・ティー・エス, 2025, 8.
Proceedings
- Yutaka Moritomo, Tomotsugu Sugano, Yuya Fukuzumi, Hiroki Iwaizumi, Takeshi Yasuda. Rapid discharge process of polythiophene cast film as cathode material. JOURNAL OF ELECTROANALYTICAL CHEMISTRY. (2019) 210-213 10.1016/j.jelechem.2019.03.054
- Takeshi Yasuda. Triphenylamine-based amorphous polymers for bulk-heterojunction photovoltaic cells. IOP CONFERENCE SERIES:MATERIALS SCIENCE AND ENGIEERING. (2014) 012015-1-012015-6 10.1088/1757-899x/54/1/012015
- Takeshi Yasuda. Anisotropic Carrier Transport Properties of Stretch-Oriented pi-Conjugated Polymers in Organic Field-Effect Transistors. PHYSICA STATUS SOLIDI C-CURRENT TOPICS IN SOLID STATE PHYSICS. (2011) 604-606 10.1002/pssc.201000405
Presentations
- 安田 剛. アモルファス有機半導体の基礎物性 ~有機ELを中心として~. 第14回TIAナノグリーン・サマースクール. 2026 Invited
- 柳生 進二郎, 長田 貴弘, 安田 剛, 中島 嘉之. 情報量規準とシフト補正付両対数プロット直線化法に基づく光電子収量分光スペクトルの高精度自動解析. 2026年 第73回 応用物理学会 春季学術講演会. 2026
- 中出 凌央, 佐藤 亮太, 安田 剛, 神原 貴樹, 桑原 純平. n型有機半導体材料を指向した2,6-ジフェニルアントラセン誘導体の合成と特性評価. 第15回 CSJ化学フェスタ2025. 2025
Misc
- 安田 剛. 有機薄膜デバイス用高分子材料の高純度・高性能化. WEB Journal. (2019) 2-5
- 安田 剛. 高信頼性アモルファス薄膜を形成するトリフェニルアミン系ドナー材料. 有機薄膜太陽電池の研究最前線(CMC出版). (2012) 53-65
- 安田 剛. トリフェニルアミン系材料を用いたバルクヘテロ型有機薄膜太陽電池の開発. 月刊ディスプレイ 6月号. 18 [6] (2012) 13-20
Published patent applications
- 近接場光学観察装置、試料含有環境セル作製方法、走査電子光学顕微鏡及び走査電子光学顕微鏡の使用方法 (2015)
- デュアルゲート有機薄膜トランジスタ (2014)
- 組成物および光電変換素子 (2014)
Society memberships
応用物理学会, 高分子学会
Research Center for Macromolecules and Biomaterials
Development of new organic semiconductors and their application in thin-film devices
Organic semiconductors, conjugated polymers, and organic thin-film devices
Overview
Organic light-emitting diodes (OLEDs) based on organic thin films have been commercialized using small-molecule semiconductors that can be fabricated by vacuum deposition. However, further development of polymer semiconductors, which are suitable for solution-based film formation, is highly desired. In addition to OLEDs, the commercialization of organic thin-film transistors (OTFTs) and organic thin-film solar cells requires the development of advanced organic semiconductors. For successful materials development, it is essential to rapidly and efficiently evaluate the properties of new organic semiconductors and device characteristics, and to provide timely feedback to the synthesis process. In this research, we select the most appropriate organic thin-film device and optimize its structure according to the properties of the organic semiconductor.
Novelty and originality
● Fabrication of organic thin-film devices utilizing the unique properties of new organic semiconductors
● Performance enhancement through device structure optimization
● Carrier mobility measurements of organic semiconductor films via diode characterization
● Structural evaluation of organic semiconductor films through emission spectrum analysis
Details
A representative example of new organic semiconductors is the fabrication and evaluation of organic thin-film devices using anthracene derivatives. The n-type semiconductor 2,6-DPA-F, featuring a pentafluorophenyl group with strong electron-accepting properties, was employed in OTFTs. Optimizing the device structure by replacing Ag electrodes with low work-function Mg resulted in high electron mobility of 0.12 cm²V⁻¹s⁻¹.
In contrast, vacuum-deposited films of TAAnt1 showed amorphous characteristics and a fluorescence quantum yield of 29%. Employing TAAnt1 as the emissive material in OLEDs, and optimizing the device structure by sandwiching the emission layer between the hole (HTL) and electron (ETL) transport layers, led to improved emission efficiency.
A specialized textbook on device physics for high-performance OLEDs has also been published (Japanese edition: Maruzen Publishing 2023; English edition: Wiley 2026). The book explains the operating principles of multilayer OLEDs using glassy amorphous organic semiconductors, and covers key topics such as tandem structures, exciplexes, molecular orientation, as well as uniquely important aspects for OLEDs, such as luminance degradation and operational lifetime.
Summary
● Comprehensive evaluation of energy levels, fluorescence quantum yield, and crystallinity of organic semiconductors to fabricate optimal organic thin-film devices
● Enhancement of device performance through structural optimization of organic thin-film devices
● Further development of coating materials for OLEDs, OTFTs, and organic thin-film solar cells, which have not yet been commercialized



