サポートされたグラフェン中の二次元フォノン輸送
Jae Hun Seol1, Insun Jo, Arden L Moore
1Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX 78712, USA.
Science (New York, N.Y.)
|April 10, 2010
まとめ
グラフェンはグラフェンです.
科学分野:
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
- ナノテクノロジー ナノテクノロジー
背景:
- グラフェンは非常に高い熱伝導性 (kappa) を表しており,ダイヤモンドやグラファイトを上回っています.
- この性質は,ナノエレクトロニクスの熱管理における潜在的な応用を示唆しています.
- しかし,基板の相互作用により,グラフェンの熱輸送特性が大幅に変化することがあります.
研究 の 目的:
- 二酸化シリコンの基板上の単層グラフェンの熱伝導性を実験的に決定する.
- 基板で支えられているグラフェンの熱性能を,懸浮グラフェンや他の材料と比較するために.
- 観測された熱伝導率の減少に起因するメカニズムを調査する.
主な方法:
- ナノスケール材料に適した技術を使用して,熱伝導性の実験的測定.
- シリコン二酸化物の基板に単層グラフェンの剥離.
- フォノン行動とインタフェース効果の分析.
主要な成果:
- シリコン二酸化物上の単層グラフェンは,室温近くで約600W/m·Kの熱伝導性を示しています.
- この値は,銅のような金属の値よりも高いままです.
- 測定された熱伝導性は,懸浮グラフェンよりも低い.
結論:
- グラフェンの高い熱伝導性は,二酸化シリコンのような基板によって支えられている場合でも部分的に保持されます.
- フォノン漏れとグラフェン・サポーター・インターフェースでのインターフェースの散乱は,熱伝送を減少させます.
- グラフェンは,基板に結合した構成でも,散熱アプリケーションの有望な材料であり続けています.
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