Study on electrical property control of pi- conjugated material by pyroelectricity and surface screening charge of polar material for environmental sensor applications

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K06284
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Electronic materials/Electric materials
• Research Institution: National Institute for Materials Science
• Principal Investigator: NAGATA Takahiro 国立研究開発法人物質・材料研究機構, 国際ナノアーキテクトニクス研究拠点, グループリーダー (10421439)
• Research Collaborator: Nakamura Tatsuru ; Yasuhara Yudai
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 焦電性 / 強誘電体 / ハイブリッド構造

Outline of Final Research Achievements

We investigated the effect of the pyroelectricity of LiNbO3 on the LiNbO3/graphene interface for the sensor application. With decreasing temperature, the resistivity increases by 2 to 3 digit and nonlinear current-voltage properties were confirmed at the single- and two-layer graphene, which is consistent with the tendency of the negative pyroelectric coefficient (-0.008 μC/Kcm2) of LiNbO3. Kelvin force microscope suggested that the electrical properties of the single-layer graphene was affected by the screen charge generated by the polarization of LiNbO3. For the three-layer graphene, the career scattering owing to the surface roughness increased the resistivity at the low temperature. The polarization and pyroelectricity of LiNbO3 has a potential for the electrical property control of graphene.

Free Research Field

無機材料物性

Academic Significance and Societal Importance of the Research Achievements

研究の特徴はLN表面のスクリーン電荷を制御し、π電子材料/強誘電体界面を用いたマイクロ・ナノエレクトロニクス素子の実現を目指す点にある。共有結合やイオン結合の強い結合で構成される無機材料のみで構成されるヘテロ接合素子では分極の影響のみの議論で問題ないが静電気力で形成されるπ電子材料/強誘電体界面においては、スクリーン電荷の影響を無視することはできない。これを制御することはπ電子材料/強誘電体界面の新たな機能を実現し、熱(焦電性)、光(光電効果)などの自然エネルギーをもちいた用いた環境センサーへ展開が可能となる。