高晶单层二硫化物在六角化物上的分子束
Deyi Fu1,2, Xiaoxu Zhao2, Yu-Yang Zhang3,4
1SinBeRISE CREATE, National Research Foundation , CREATE Tower, 1 Create Way, Singapore 138602, Singapore.
Journal of the American Chemical Society
|June 22, 2017
概括
研究人员开发了一种可扩展的方法,用于在六角化物 (h-BN) 上合成高晶二硫化物 (MoS2) 薄膜. 这一突破使得先进的电子和光电子产品的统一大面积生产成为可能.
科学领域:
- 材料科学
- 凝聚物质物理学
- 纳米技术
背景情况:
- 原子薄的二硫化 (MoS2) 是电子和光电子的有前途的直带间隙半导体.
- 在实际应用中,高晶度MoS2薄膜的可扩展合成仍然是一个重大挑战.
研究的目的:
- 实现连续,均,高度结晶的单层MoS2膜的可扩展,表层生长.
- 在六角化物 (h-BN) 上研究和控制MoS2的核和生长机制.
主要方法:
- 使用分子光束表 (MBE) 的表生长.
- 使用六角化物 (h-BN) 作为MoS2生长的基质.
- 使用高生长温度和超低的前体流量.
- 通过原子力显微镜 (AFM) 和电子显微镜进行表征.
主要成果:
- 在h-BN上成功生长连续的,均的,高度结晶的单层MoS2膜.
- 在MoS2中识别了两个主要的核化颗粒类型 (0°和60°域).
- 通过优化生长条件 (高温,低流量) 抑制60°反对齐的域.
- 具有良好的空间均性的大规模 (2英寸晶圆) MoS2膜生长的演示.
结论:
- 这项研究在高质量的MoS2膜的可扩展合成方面取得了重大进展.
- 优化的MBE生长条件使得完美对齐的MoS2粒形成,从而形成高度晶体的薄膜.
- 这种方法为在电子和光电子设备中大规模集成MoS2铺平了道路.
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