シリコン pn 接合点における摩擦の電子制御
Jeong Young Park1, D F Ogletree, P A Thiel
1Materials Sciences Division, Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720, USA.
Science (New York, N.Y.)
|July 15, 2006
まとめ
シリコンの摩擦力は,キャリア濃度を調整することによって電子的に制御できます. この発見は,半導体装置やナノスケールマシンにおける摩擦調節の可能性を広げています.
科学分野:
- マテリアルサイエンス 材料科学
- 固体物理 固体物理学
- トリボロジー トリボロジ トリボロジ
背景:
- 摩擦は,機械システムの性能と寿命の重要な要因です.
- ナノスケールでの摩擦を制御することは,高度なマイクロおよびナノ電気機械システム (MEMS/NEMS) の開発に不可欠です.
- 摩擦制御のための既存の方法は,しばしば精度や適応性が欠けている.
研究 の 目的:
- ドーピングされたシリコンにおけるキャリア濃度と摩擦力との関係を調査する.
- 半導体材料における摩擦の電子制御を実証する.
- ナノスケールデバイスにおける潜在的な応用を探求する.
主な方法:
- サンプルとしてドーピングされたシリコン基板 (n型Si100とp型ストライプ) を使った.
- 原子力顕微鏡 (AFM) の先端を,カウンター表面としてチタン窒化物でコーティングした.
- AFMの先端とサンプルに前方/逆のバイアス電圧を適用することによって,局所キャリア濃度を調節します.
主要な成果:
- ドーピングされたシリコンのキャリア濃度に対する摩擦力の有意な依存を観察した.
- 電荷の枯渇または蓄積が摩擦に直接影響することを実証した.
- 適用されたバイアス電圧による摩擦力の実質的な差異を定量化.
結論:
- 半導体装置における摩擦の電子制御は実現可能である.
- キャリア濃度は,摩擦力を調節するための重要なパラメータです.
- 潜在的な応用には,ナノスケールの機械やデバイスにおける摩擦調節が含まれます.
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