Growth, structure, and morphology of van der Waals epitaxy Cr1+δTe2 films

Nanoscale Research Letters

Research

Hui-Qiong Wang¹  Xiaodan Wang²  Lihui Bai³  Hua Zhou³ 

[1] Engineering Research Center of Micro-Nano Optoelectronic Materials and Devices, Ministry of Education; Fujian Key Laboratory of Semiconductor Materials and Applications, CI Center for OSED, and Department of Physics, Xiamen University, 361005, Xiamen, People’s Republic of China;Engineering Research Center of Micro-Nano Optoelectronic Materials and Devices, Ministry of Education; Fujian Key Laboratory of Semiconductor Materials and Applications, CI Center for OSED, and Department of Physics, Xiamen University, 361005, Xiamen, People’s Republic of China;School of Physics, Shandong University, 250100, Jinan, People’s Republic of China;School of Physics, Shandong University, 250100, Jinan, People’s Republic of China;

关键词: CrTe;    Scanning tunneling microscopy;    Film growth;    Surface structure;    Morphology evolution;    Mica;   

DOI  :  10.1186/s11671-023-03791-y

 received in 2022-12-03, accepted in 2023-02-07,  发布年份 2023

来源: Springer

【 摘 要 】

The preparation of two-dimensional magnetic materials is a key process to their applications and the study of their structure and morphology plays an important role in the growth of high-quality thin films. Here, the growth, structure, and morphology of Cr1+δTe2 films grown by molecular beam epitaxy on mica with variations of Te/Cr flux ratio, growth temperature, and film thickness have been systematically investigated by scanning tunneling microscopy, reflection high-energy electron diffraction, scanning electron microscope, and X-ray photoelectron spectroscopy. We find that a structural change from multiple phases to a single phase occurs with the increase in growth temperature, irrespective of the Cr/Te flux ratios, which is attributed to the desorption difference of Te atoms at different temperatures, and that the surface morphology of the films grown at relatively high growth temperatures (≥ 300 °C) exhibits a quasi-hexagonal mesh-like structure, which consists of nano-islands with bending surface induced by the screw dislocations, as well as that the films would undergo a growth-mode change from 2D at the initial stage in a small film thickness (2 nm) to 3D at the later stage in thick thicknesses (12 nm and 24 nm). This work provides a general model for the study of pseudo-layered materials grown on flexible layered substrates.

【 授权许可】

CC BY   
© The Author(s) 2023

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