TRMC@Inerfaces: Electron Mobility Measurement at Conjugated Molecules-Insulators Interfaces

2016 Fiscal Year Final Research Report

• Project/Area Number: 26620104
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Polymer chemistry
• Research Institution: Kyoto University (2015-2016); Osaka University (2014)
• Principal Investigator: SEKI Shu 京都大学, 工学研究科, 教授 (30273709)
• Research Collaborator: CHOI Wookjin 京都大学, 大学院工学研究科, 研究員 ; TSUTSUI Yusuke 京都大学, 大学院工学研究科, 研究員 ; MATSUDA Wakana
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: Interfaces / マイクロ波 / 移動度 / 伝導度 / 高分子構造 / 界面

Outline of Final Research Achievements

Field-Induced Time-Resolved Microwave Conductivity (FI-TRMC) measurement technique has been developed to probe local motion of charge carriers at polymeric dielectrics-organic semiconductor interfaces. This technique revealed high potential of several isomers with BTBT or BBTBDT core unit as positive charge conductors. Structural analysis of the high potential isomers at the interfaces showed unique herringbone-type structures with 2D pathways stabilized by the Sulfur-Sulfur interactions for the charge carriers, which was also confirmed by the DFT based theoretical calculations. The carrier diffusion model over the 2D transport layers has successfully reproduced the transport mechanisms in the active layers based on not only the above compounds but also the other organic semiconductor molecules, showing wide applicability of the present models to deduce intrinsic value of mobility as well as the determinant processes including trap density, depth, and free/trapped charge carrier ratio.

Free Research Field

物性物理化学