Research and Development Center for Semiconductor Lighting Technology, Institute of Semiconductors, Chinese Academy of Sciences, Beijing, 100083, P. R. China.
Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences, Beijing, 100049, P. R. China.
Adv Mater. 2023 May;35(18):e2211075. doi: 10.1002/adma.202211075. Epub 2023 Mar 20.
Beyond traditional heteroepitaxy, 2D-materials-assisted epitaxy opens opportunities to revolutionize future material integration methods. However, basic principles in 2D-material-assisted nitrides' epitaxy remain unclear, which impedes understanding the essence, thus hindering its progress. Here, the crystallographic information of nitrides/2D material interface is theoretically established, which is further confirmed experimentally. It is found that the atomic interaction at the nitrides/2D material interface is related to the nature of underlying substrates. For single-crystalline substrates, the heterointerface behaves like a covalent one and the epilayer inherits the substrate's lattice. Meanwhile, for amorphous substrates, the heterointerface tends to be a van der Waals one and strongly relies on the properties of 2D materials. Therefore, modulated by graphene, the nitrides' epilayer is polycrystalline. In contrast, single-crystalline GaN films are successfully achieved on WS . These results provide a suitable growth-front construction strategy for high-quality 2D-material-assisted nitrides' epitaxy. It also opens a pathway toward various semiconductors heterointegration.
除了传统的异质外延，二维材料辅助外延为未来的材料集成方法开辟了变革的机会。然而，二维材料辅助氮化物外延的基本原理仍不清楚，这阻碍了对其本质的理解，从而阻碍了其发展。在这里，我们从理论上建立了氮化物/二维材料界面的晶体学信息，并通过实验进一步证实了这一点。研究发现，氮化物/二维材料界面的原子相互作用与底层衬底的性质有关。对于单晶衬底，异质界面表现为共价键性质，外延层继承了衬底的晶格。而对于非晶衬底，异质界面倾向于范德华键性质，并且强烈依赖于二维材料的性质。因此，在石墨烯的调制下，氮化物的外延层是多晶的。相比之下，在 WS2 上成功地获得了单晶 GaN 薄膜。这些结果为高质量的二维材料辅助氮化物外延提供了合适的生长前沿构建策略。它也为各种半导体异质集成开辟了道路。
