グラフェン・バッファリングされたサファイア上のストレスのないAlNの急速な成長
Yue Qi, Yunyu Wang1,2, Zhenqian Pang3,4
1Research and Development Center for Solid State Lighting , Institute of Semiconductors, Chinese Academy of Sciences , Beijing 100083 , China.
Journal of the American Chemical Society
|September 4, 2018
まとめ
グラフェンバッファレイヤは,欠陥とストレスを軽減することによって,サファイアのアルミニウム窒化物 (AlN) 膜の成長を大幅に改善します. これは,発光ダイオードアプリケーションの AlN 品質を向上させます.
科学分野:
- 材料科学
- ナノテクノロジー
- 半導体物理学
背景:
- サファイア基板は,アルミニウムニトリド (AlN) 膜の成長のために一般的に使用されます.
- AlNとサファイルの間の格子と熱膨張の不一致は,高い欠陥密度とストレスを引き起こす.
- グラフェンのユニークな性質は,新しいバッファレイヤの応用の可能性を提供します.
研究 の 目的:
- 石英のAlN膜の成長のためのバッファー層としてのグラフェンの役割を調査する.
- グラフェンがAlNの核形成,成長率,欠陥形成にどのように影響するかを理解する.
- AlN/サファイア系におけるストレスの緩和に対するグラフェンの影響を評価する.
主な方法:
- 薄いグラフェンフィルムは,サファイア基板と成長するAlNフィルムの間のインターレイヤーとして使用されました.
- AlN膜の成長は,核形成密度,成長率,および脱位進化を分析する技術を用いて特徴づけられました.
- AlNとサファイアの両方のストレンス状態は,グラフェン中間層の効果を評価するために測定されました.
主要な成果:
- グラフェンはAlN核の密度を低下させましたが,個々の核の成長率を増加させました.
- グラフェンの存在は,凝結境界でのスレッド変位の減少につながった.
- グラフェンは格子と熱膨張の不一致を効果的に取り入れ,AlNとサファイアの両方のストレスを大幅に緩和しました.
- ストレスの緩和は,AlNフィルムの全体的な欠陥密度が低い結果となりました.
結論:
- グラフェンは効果的な緩衝層として機能し,サファイアに育てられたAlNフィルムの品質を大幅に改善します.
- この研究は,高性能の光電子機器に不可欠な,ストレスを軽減し,欠陥を軽減するグラフェンの役割を強調しています.
- これらの発見は,III-ニトリドの成長と高度な発光ダイオードの開発におけるグラフェンの適用のための貴重な洞察を提供します.
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