GaN/NbN エピタキシアル半導体/超導体ヘテロ構造
Rusen Yan1, Guru Khalsa2, Suresh Vishwanath1
1School of Electrical and Computer Engineering, Cornell University, Ithaca, New York 14853, USA.
Nature
|March 9, 2018
まとめ
研究者は分子ビームエピタキシを用いて,ニオビウムニトリド (NbN) 超伝導体上に半導体ヘテロ構造を直接成長させました. 超伝導性と半導体の性質を組み合わせた 新しい電子装置が実現しました
科学分野:
- 材料科学
- 凝縮物質物理学
- 固体化学
背景:
- 半導体ヘテロ構造の結晶型超伝導体の直接的表軸成長は困難である.
- ニオビウム窒素 (NbN) は結晶型超伝導体である.
- ワイドバンドギャップ半導体には,炭化水素,ガリウム窒化物 (GaN),およびアルミニウムガリウム窒化物 (AlGaN) が含まれる.
研究 の 目的:
- 半導体ヘテロ構造が結晶型超伝導体で直接表軸的に成長することを実証する.
- ナイオビウム窒素 (NbN) ベースの超伝導体を広帯域半導体と統合する.
- 超伝導と半導体の性質を組み合わせた新しい電子機器の可能性を調査する.
主な方法:
- 分子ビームエピタキシ (MBE) が堆積に使用された.
- AlGaN/GaN量子ウェルヘテロ構造は,超薄結晶のNbN超伝導体上に直接培われた.
- 超伝導体をソースロードとして利用した半導体トランジスタの製造.
主要な成果:
- NbN超伝導体とAlGaN/GaNヘテロ構造の統合に成功した.
- 2次元電子ガスにおける量子振動の観測により,高移動性を示した.
- 超伝導体で製造されたマイナス差電阻 (NDR) の半導体トランジスタの実証.
結論:
- 高品質の半導体ヘテロ構造と装置の結晶性ニトリド超伝導体上の直接的表軸成長は可能である.
- この統合は,超伝導体のマクロスコーピック量子効果とIII-ニトリド半導体の電子,光子,およびピエゾ電気的性質を組み合わせる可能性を開きます.
- 開発された技術は,新しいタイプの増幅器や振動器につながる可能性があります.
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