半金属と単層半導体間の超低コンタクト抵抗
Pin-Chun Shen1, Cong Su2,3,4,5, Yuxuan Lin6,7
1Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology (MIT), Cambridge, MA, USA. pcshenc@tsmc.com.
Nature
|May 13, 2021
まとめ
研究者はビスムスを用いて二次元半導体の超低抵抗オームコンタクトを達成しました. この突破は エネルギー障壁をなくし 高性能トランジスタを可能にし 進化した電子機器のムーアの法則を 拡張する可能性があります
科学分野:
- 材料科学
- 凝縮物質物理学
- ナノテクノロジー
背景:
- 先進的な電子機器には 新しいチャネル材料と シリコン以外の超低抵抗コンタクトが必要です
- 二次元 (2D) 半導体は高性能デバイスの可能性を秘めているが,金属誘発のギャップ状態 (MIGS) に起因する高接触抵抗によって制限されている.
研究 の 目的:
- 2D半導体トランジスタのための超低抵抗オームコンタクトを開発する.
- 金属半導体界面における金属誘発のギャップ状態によって課される制限を克服する.
主な方法:
- 半金属ビスムスと半導体単層移行金属二カルゴニド (TMD) の間のオーム接触形成を調査した.
- MIGSを抑制し,インターフェイスでTMDの変性状態を誘導するためにビスムスを利用しました.
主要な成果:
- モノレイヤ MoS2のビスムート接触でショットキーバリアの高さゼロを達成しました.
- 123 Ω·μmの記録的な低い接触抵抗と1,135 μA/μmの記録的な高いオン状態の電流密度を示した.
- MoS2,WS2,およびWSe2を含む様々な単層半導体でオームコンタクトを成功裏に形成しました.
結論:
- 開発されたビスマスコンタクトは,2D半導体のコンタクト抵抗を大幅に改善し,量子限界に近づいています.
- この技術は,最先端の3D半導体に匹敵する高性能単層トランジスタを可能にします.
- この発見により デバイスの縮小や ムーアの法則の拡張が 可能になりました
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