Elucidation of charge injection process of self-contact organic transistor using accumulated charge method

2019 Fiscal Year Final Research Report

• Project/Area Number: 17K18020
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Functional solid state chemistry; Device related chemistry
• Research Institution: University of Hyogo
• Principal Investigator: Kadoya Tomofumi 兵庫県立大学, 物質理学研究科, 助教 (70759018)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 有機トランジスタ / 分子性導体 / 有機半導体 / 有機結晶

Outline of Final Research Achievements

Crystal structure of organic semiconductor Br-BTBT-4 was analyzed and transistor characteristics were evaluated. The BTBT-C4 in the previous study formed a bi-layer type herringbone arrangement, whereas Br-BTBT-C4 formed a conventional herringbone array. It should be noted that the molecular packing in the herringbone was more dense in Br-BTBT-C4 than in BTBT-C4. We have succeeded in developing new molecular conductors (BSBS)2AsF6 and (BSBS)2SbF6 using benzoselenobenzoselenophene (BSBS), a molecule in which sulfur of benzothienobenzothiophene (BTBT) is replaced by selenium. Single crystal structure analysis, electric conductivity and thermoelectric power measurements were performed. These complexes have isomorphic structures with the previously reported (BTBT)2XF6 complexes. The conductivity was 850 S/cm for the AsF6 complex and 650 S/cm for the SbF6 complex. The thermoelectric power was about 15-17 microV/K, and the power factor was 15-24 microW/K2.

Free Research Field

有機材料化学

Academic Significance and Societal Importance of the Research Achievements

トランジスタ分子を含む分子性導体の物性から、分子軌道計算でしか評価できなかった分子間相互作用の値を実験によって見積もることができる手法を拡大した。関連分野に強いインパクトを与えると考えられる。今後は新たな熱電素子を探索しながら、類縁体の分子のトランスファー積分を見積もる。また、分子性導体の分野で主流であったTTF骨格ではない分子を用いて、二次元電子構造をもつ強相関電子系を開発できたことは非常に稀である。このことは、今回用いた、BEDT-BDT骨格が新しい分子性導体の開発に有望な骨格であることを示しており、熱電性能だけではない、新しい物性開拓が期待される。