ドーピングされていないCVDダイヤモンドフィルムの電気輸送特性
まとめ
マイクロ波による化学蒸気堆積 (MACVD) は,高移動性の多結晶ダイヤモンドフィルムを生成しました. しかし,粒子の内部に欠陥があるため,キャリア・ドリフトの長さは制限され,全体的な性能に影響を及ぼします.
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
- ナノテクノロジー ナノテクノロジー
背景:
- 多結晶ダイヤモンドフィルムは,マイクロ波補助化学蒸気堆積 (MACVD) を含む様々な技術を使用して合成されます.
- キャリアモビリティや寿命などの電気輸送特性を理解することは,ダイヤモンドフィルムの品質と潜在的なアプリケーションを評価するために不可欠です.
研究 の 目的:
- MACVDで合成された多結晶ダイヤモンドフィルムの電気伝送特性を調査する.
- キャリアの移動性と寿命を測定し,これらの性質に影響を与える要因を分析する.
主な方法:
- ダイヤモンドフィルムを研究するために,一時的な光伝導性測定が採用されました.
- キャリアの移動性と寿命は,実験データから決定された.
主要な成果:
- 最も高い測定されたキャリアモビリティは,低キャリア密度 (<1015cm−3) で50cm2/Vsであった.
- 電子穴の散乱により,より高い密度でキャリアの移動性が低下した.
- キャリア寿命は約40ピコ秒と推論され,キャリア漂流の長さは粒内欠陥によって制限された.
結論:
- MACVDで合成された多結晶ダイヤモンドフィルムは,低品質のDCプラズマフィルムと比較して有望なキャリアモビリティを示しています.
- これらのフィルムの性能は,粒子のサイズと粒子の内欠陥によって大きく影響され,キャリア輸送を制限します.
- 単結晶天然ダイヤモンドの電気的性質に近づくためには,合成条件のさらなる最適化が必要である.
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