シリコンフォトニックバンドギャップ結晶のオンチップの自然組成
Y A Vlasov1, X Z Bo, J C Sturm
1NEC Research Institute, 4 Independence Way, Princeton, New Jersey 08540, USA.
Nature
|November 20, 2001
まとめ
研究者らは,コロイド球のセルフアセンブリを用いた単結晶シリコン光学結晶を開発した. これらの構造は強固な光子帯域ギャップを示し,全光学集積回路への道を開く.
科学分野:
- マテリアルサイエンス 材料科学
- オプティクスは光学です.
- ナノテクノロジー ナノテクノロジー
背景:
- フォトニック・バンドギャップ・クリスタルは,光伝播の制御を提供しており,これは全光学集積回路にとって極めて重要です.
- フォトニック結晶の従来の製造方法は複雑で高価です.
- コロイド球の自然組立は,より簡単な経路を提供しますが,光子帯域のギャップを損なう欠陥をもたらします.
研究 の 目的:
- 高品質の単結晶シリコン光学結晶を作成する方法を開発する.
- これらの構造における光子帯域ギャップの存続を証明するために.
- デバイスの応用の可能性を,さらなる製造段階を通して探求する.
主な方法:
- シリコン基板上のコロイド球の自己組み立てにより,平らな単結晶構造を形成します.
- フォトニックバンドギャップ特性と欠陥密度の特徴.
- ドーピングやパターニングなどの追加の製造ステップの実証.
主要な成果:
- 欠陥密度が低い平面,単結晶のシリコン光学結晶を達成しました.
- 特定の結晶方向で約1.3マイクロメートルの単位反射率が観測され,生き残った光子帯間隙が確認されました.
- ドーピングとパターニングを成功裏に実行し,デバイス製造に適していることを示しました.
結論:
- コロイド球の自己組み立て法により,光学アプリケーションに適した高品質のシリコン光学結晶が得られます.
- 構造と特性に対する実証された制御は,高度な光子装置の可能性を開きます.
- このアプローチは,光子結晶の製造に潜在的によりシンプルでより費用対効果の高い経路を提供します.
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