ナフトジチオフェン半導体ポリマーのトランジスタ性能に対する同位体構造の影響
Itaru Osaka1, Toru Abe, Shoji Shinamura
1Department of Chemistry, Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8527, Japan. iosaka@hiroshima-u.ac.jp
Journal of the American Chemical Society
|April 12, 2011
まとめ
ポリチオフェンバックボーンの角性ナフトジオフェン (NDT) は,有機半導体における電荷キャリアの移動性を著しく高めます. 角形のNDT3を持つポリマーは,強化された分子オーダーリングと電子デロカライゼーションにより優れた性能を示しました.
科学分野:
- オーガニック・エレクトロニクス
- マテリアルサイエンス 材料科学
- ポリマー化学 ポリマー化学
背景:
- ポリチオフェン半導体は,有機電子機器にとって極めて重要です.
- ナフトドチオフェン (NDT) は,半導体性能を改善するための構成要素として調査されています.
- 構造と性質の関係を理解することは,高性能材料の設計の鍵です.
研究 の 目的:
- ポリチオフェン半導体性能に対する線形および角形ナフトジオフェン (NDT) イソマーの影響を調査する.
- NDTベースのポリマーの分子構造と電荷キャリアの移動性を相関させるため.
- 高性能有機フィールド効果トランジスタのための有望なNDT構造を特定する.
主な方法:
- 4つの同位体NDTベースのポリチオフェン半導体の合成.
- チャージキャリアの移動性を含むフィールド効果トランジスタの性能の特徴.
- ポリマーの構造的順序と π スタッキングを決定するX線 difraktion 分析.
- 電子構造を分析するために分子軌道 (MO) 計算とイオン化ポテンシャル測定を行います.
主要な成果:
- 角型NDT3のポリマーは,最も高い流動性 (∼0.8cm2 V−1s−1) を示し,半導体ポリマーで報告されている中で最も高い流動性を示した.
- 予想に反して,角型NDTポリマーは,線形NDTポリマーよりも高い移動性を示した.
- X線 difraktionでは,線形NDTポリマーとは異なり,角形NDTポリマーでは,密接なπ-スタッキング (3.6 Å) を有する高度に秩序付けられた構造を明らかにしました.
- MO計算は,角型NDTポリマーの脊髄に沿って異地化されたHOMOを示し,効率的な電荷輸送を促進しました.
結論:
- 角型NDT,特にNDT3は,高性能半導体ポリマーのための有望なコアです.
- 分子形と電子構造は,高効率の電荷キャリア輸送をポリマーで設計するための重要な要因です.
- 角形のNDTによって与えられている擬似直線脊柱は,高度に秩序付けられた梱包と改善された移動性を促進します.
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