オキシードナノ構造の自発的なオーダーリング
1Department of Materials and Nuclear Engineering, Department of Physics, University of Maryland, College Park, MD 20742, USA. Flat Panel Display Division, Motorola Inc., 7700 South River Parkway, Tempe, AZ 85284, USA.
まとめ
酸化過程で薄いパラジウム膜に,オキシードパラジウム"チップ"の均一な配列が自発的に形成されます. 膜の厚さと加工条件は,先端のサイズと密度に影響し,フィールドエミッションアプリケーションの可能性を示唆しています.
科学分野:
- マテリアルサイエンス 材料科学
- 表面科学とは,地表科学である.
- ナノテクノロジー ナノテクノロジー
背景:
- パラジウム (Pd) 薄膜は,様々な電子的および触媒的アプリケーションにおいて不可欠です.
- 薄膜のナノ構造の形成を制御することは,高度な材料特性にとって不可欠です.
研究 の 目的:
- パラジウム薄膜酸化中のナノ構造物の自発的形成を調査する.
- フィルムの特性,加工条件,ナノ構造体形態学の関係を理解する.
- これらのナノ構造物の潜在的な応用を探求する.
主な方法:
- 厚さが異なる (40-200 nm) パラジウム薄膜の酸化.
- 結果となるナノ構造物の特徴化 (尖端/ヒロック).
- 薄膜の厚さ,粒度,アニリング,酸化条件の影響の分析.
- フォトエレクトロン放出特性の測定.
主要な成果:
- 円筒状のパラジウム酸化物尖端の均一な配列が自発的に形成された.
- 尖端の高さはフィルム厚さの増加とともに0.5から1.2μmに増加した.
- 尖端の密度は55x10^6から12x10^6cm^-2に減った.
- 厚いフィルムで観察されたより広い高さ分布.
結論:
- パラジウム膜の厚さと酸化条件が,酸化先の形成と形状を決定する.
- 観測された先端は,光電子の放出が強化されたことを示している.
- これらのパラジアム酸化物の先端は,フィールドエミッションデバイスのアプリケーションに希望を示しています.
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