2次元半導体コンタクトで量子限界に近づく
Weisheng Li1, Xiaoshu Gong2, Zhihao Yu1
1National Laboratory of Solid State Microstructures, School of Electronic Science and Engineering and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.
Nature
|January 11, 2023
まとめ
2D電子機器の超低抵抗電気コンタクトを作成するためにアンチモンを用いた新しい方法を開発しました. この突破はモリブデン二酸化物トランジスタの性能と安定性を向上させ,シリコン技術を上回り,将来のロードマップの目標を達成します.
科学分野:
- 材料科学
- 電気工学
- ナノテクノロジー
背景:
- 次世代の電子機器には 超薄なチャネル材料と 低い接触抵抗が必要です
- 移行金属二カルコゲニドは,継続的なトランジスタスケーリングの可能性を秘めています.
- 2D素材の現在の接触技術は,バン・デル・ワールスのギャップと安定性の問題により制限されています.
研究 の 目的:
- 単層モリブデン・ジスルファイドの 量子限界に近い電気的接触を 達成する.
- 2D電子機器の性能と安定性を向上させる
- 2Dエレクトロニクスの新しい接触材料としてアンチモンを探索する.
主な方法:
- 強力なヴァン・ダー・ワールズ相互作用による半金属アンチモンの単層モリブデン・ディスルファイドのエネルギー帯の混合化.
- 短チャンネルモリブデンジスルファイドトランジスタとアンチモンのコンタクトの製造
- コンタクト抵抗,オン状態の電流,オン/オフ比率を含むデバイスの性能の特徴.
- 高温で装置の安定性をテストし,大面積の配列での変動性を評価する.
主要な成果:
- 42オームマイクロメートルの低接触抵抗を達成しました.
- 125°Cで 絶好の安定性を示した
- ショートチャネルトランジスタは1Vの電流飽和度,オン状態の電流1.23mA/μm,オン/オフ比>10^8,および固有遅延74fsを示した.
- 2028年のロードマップ目標を達成しました.
- 大面積の配列で重要なデバイスのパラメータの低変動を示した.
結論:
- アンチモンの接触は モリブデンジスルファイドの電気性能を 量子限界に近づけます
- 開発されたコンタクトは,優れた安定性と低変動性を提供し,実用的なアプリケーションに不可欠です.
- アンチモンは,シリコンの能力を超えた移行金属ディカルコゲン化物ベースの電子を進歩させるための有望な接触技術を提示しています.
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