有機分子半導体における断片量子ホール効果
1Bell Laboratories, Lucent Technologies, 600 Mountain Avenue, Murray Hill, NJ 07974, USA.
Science (New York, N.Y.)
|July 6, 2000
まとめ
高品質の有機半導体は,新しいデバイスで高電荷キャリアの移動性を達成しました. これらの材料は,断片的量子ホール状態を含む量子現象を示し,高度な電子学の道を開いた.
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
- オーガニック・エレクトロニクス
背景:
- 有機分子半導体は,新しい電子アプリケーションの可能性を秘めています.
- 高電荷キャリアの移動性を達成し,これらの材料における量子現象を観察することは,デバイスの進歩にとって極めて重要です.
研究 の 目的:
- 高品質のテトラセーンとペンタセンの結晶の電子特性を調査する.
- これらの有機半導体を使用した金属分離器半導体 (MIS) デバイスの製造と特徴付け.
- これらの有機フィールド効果トランジスタにおける量子現象の顕在化を探求する.
主な方法:
- 高品質のテトラセーンとペンタセンの単結晶の製造.
- メタル・インソレーター・セミコンダクター (MIS) 構造物の製造.
- モビリティ測定を含むデバイスの性能の電気的特徴.
- シュブニコフ・デ・ハース振動と量子ホール効果の調査.
主要な成果:
- MISデバイスで10^4cm^2/Vsを超える穴と電子の移動性を達成しました.
- ゲート電圧制御のキャリア濃度で実証された両極性フィールド効果行動.
- よく定義されたシュブニコフ・デ・ハースの振動と,10^11cm^-2.2の2Dキャリア密度で量子化されたホール高原を観測した.
- ~2ケルビンまでの温度でテトラセンの結晶で報告された分数量子ホール状態.
結論:
- 高品質の有機半導体は,高電荷キャリアの移動性をサポートすることができます.
- オーガニック・フィールド・エフェクト・トランジスタは,分数量子ホール状態を含む複雑な量子現象を現すことができます.
- これらの発見は,先進的な電子および量子アプリケーションのための有機材料の可能性を強調しています.
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