超快的范德瓦尔斯二极管使用石墨烯量子电容和费米级解脱
Sungjae Hong1, Chang-Ui Hong2, Sol Lee1,3
1Department of Physics, Van der Waals Materials Research Center, Yonsei University, Seoul 03722, Republic of Korea.
Science advances
|July 19, 2023
概括
在垂直二极管中插入石墨烯显著提高了超高频率的性能. 这种增强是由于石墨烯.
科学领域:
- 材料科学 材料科学 材料科学
- 电气工程 电气工程
- 凝聚物质物理学 凝聚物质物理学
背景情况:
- 石墨烯的电气特性使其在堆叠的设备中变得有用.
- 它在金属半导体连接处的作用是众所周知的低频.
- 石墨烯插入的高频应用尚未得到充分探索.
研究的目的:
- 研究石墨烯在超高频率下对垂直二极管的影响.
- 使用MoSe2和石墨烯演示二极管操作.
- 分析石墨烯半导体接口的依赖频率的行为.
主要方法:
- 垂直Pt/n-MoSe2/石墨烯/Au二极管结构的制造.
- 测量设备性能高达200 GHz的频率.
- 分析电荷传输机制和电容效应.
主要成果:
- 在~200 GHz的截止频率 (fC) 实现了二极管运行.
- 由于量子电容,石墨烯的电荷调制在几GHz以上就会结.
- 转换了欧米石墨烯/MoSe2 连接到一个没有固定的 Schottky 连接.
- 与没有石墨烯的设备相比,总容量显著降低.
结论:
- 插入石墨烯可以提高超高频二极管的性能.
- 量子电容效应是高频操作的关键.
- 石墨烯是用于高频电子设备的有希望的材料.
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