高流动性二维半导体的最佳电子结构:二维反中异常高的孔流动性
Long Cheng1, Chenmu Zhang1, Yuanyue Liu1
1Texas Materials Institute & Department of Mechanical Engineering , The University of Texas at Austin , Austin , Texas 78712 , United States.
Journal of the American Chemical Society
|September 26, 2019
概括
研究人员发现单层 (Sb) 具有异常高的孔移动性,超过其他二维半导体. 这一发现为克服先进电子应用中的移动性限制提供了有希望的解决方案.
科学领域:
- 材料科学
- 凝聚物质物理学
- 固态化学
背景情况:
- 二维 (2D) 半导体为光电化学等应用提供独特的特性.
- 在室温下低电荷载体的移动性仍然是二维半导体开发的重大挑战.
研究的目的:
- 发现具有高内在电荷载体移动性的新型二维材料.
- 研究二维材料中的电子结构和移动性之间的关系.
- 确定未来高流动性二维半导体的设计原则.
主要方法:
- 使用博尔兹曼运输理论进行准确的移动计算.
- 使用第一原则计算来确定散射率.
- 分析了单层 (Sb) 的电子带结构.
主要成果:
- 在单层Sb中发现异常高的内在孔移动性 (∼1330 cm2 V-1 s-1) 在室温下.
- 单层Sb比MoS2,InSe和黑具有更高的流动性.
- 在 Γ 点确定了一个尖的,深厚的带谷作为高流动性的关键.
结论:
- 单层Sb是一种非常有前途的二维材料,用于需要高电荷载体移动性的应用.
- Sb 独特的电子结构可最大限度地减少散射,从而提高性能.
- 在 Γ 点的深带谷可以作为设计高流动性的 2D 半导体的目标特征.
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