マイクロクリスタリンポリマー半導体における電荷载波関数の現実的な記述
D L Cheung1, D P McMahon, A Troisi
1Department of Chemistry and Centre of Scientific Computing, University of Warwick, CV4 7AL Coventry, UK.
Journal of the American Chemical Society
|July 23, 2009
まとめ
コンピューティング化学は,多3ヘキシルチオフェン (P3HT) 半導体ポリマーの局所的な電荷キャリアと長寿命のトラップを明らかにします. これは,ポリマー相順に活性化された輸送を説明し,トラップ状態を初めて詳細に説明します.
科学分野:
- マテリアルサイエンス 材料科学
- コンピューティング・ケミストリー
- ポリマーサイエンスの科学
背景:
- ポリー ((3-ヘキシルチオフェン) (P3HT) は,広く使用されている半導体ポリマーです.
- チャージキャリアの振る舞いを理解することは,ポリマーエレクトロニクスにとって極めて重要です.
- 既存のモデルは,しばしば微細な詳細が欠けています.
研究 の 目的:
- P3HT.における電荷媒体の電子構造を解明する.
- オーダーされたポリマー相における活性化輸送の背後にあるメカニズムを説明する.
- 閉じ込められた状態の化学的詳細な説明を提供するために.
主な方法:
- 古典的および量子化学的計算方法の組み合わせ.
- 充電キャリアの位置の分析.
- 結晶P3HT.で閉じ込められた状態の調査.
主要な成果:
- P3HTの電荷キャリアは,長寿命のトラップにより局所化されています.
- これらの罠は,結晶段階でも存在します.
- オーダーされたP3HTでの活性化輸送は,ポラロンエネルギーに関係なく説明されます.
- 閉じ込められた状態は,前例のない化学的な詳細で記述されています.
結論:
- 計算化学は,ポリマーにおける電荷輸送の現象学的記述と顕微鏡学的記述の間のギャップを埋めます.
- この研究は,P3HT.の電荷キャリアの局所化と輸送メカニズムの詳細な理解を提供します.
- この研究は,改良された半導体ポリマーの設計のための基礎を提供します.
関連する概念動画
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The generation of electrical current in semiconductors is fundamentally driven by two mechanisms: drift and diffusion. These processes are essential for the functionality and performance of semiconductor-based devices.
Drift Current:
The drift of charge carriers is started by an external electric field (E). Charged particles, such as electrons and holes, experience an acceleration between collisions with lattice atoms. For electrons, this results in a drift velocity (vd) given by:
Drift Current:
The drift of charge carriers is started by an external electric field (E). Charged particles, such as electrons and holes, experience an acceleration between collisions with lattice atoms. For electrons, this results in a drift velocity (vd) given by:
01:22Semiconductors
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01:20Types of Semiconductors
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01:22Carrier Generation and Recombination
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Indirect generation involves an...
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Indirect generation involves an...
01:12Fermi Level Dynamics
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The work...
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The work...
01:18Fermi Level
The Fermi-Dirac function is represented by an S-shaped curve indicating the probability of an energy state being occupied by an electron at a given temperature. The Fermi level is the energy level at which there is a fifty percent chance of finding an electron, and it is positioned between the lower-energy valence band and the higher-energy conduction band.
At absolute zero temperature, electrons fill all energy states up to the Fermi level, leaving upper states empty. As the temperature rises,...
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