Open AccessIn situ reflection electron microscopy for investigation of surface processes on Bi2Se3(0001)
Author(s) -
С. А. Пономарев,
Д. И. Рогило,
N. N. Kurus,
L. S. Basalaeva,
К. А. Кох,
A. G. Milekhin,
D. V. Sheglov,
А. В. Латышев
Publication year - 2021
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1984/1/012016
Subject(s) - sublimation (psychology) , epitaxy , electron diffraction , nucleation , van der waals force , materials science , molecular beam epitaxy , surface reconstruction , crystallography , analytical chemistry (journal) , chemistry , optics , diffraction , nanotechnology , layer (electronics) , geometry , physics , organic chemistry , mathematics , surface (topology) , psychology , chromatography , molecule , psychotherapist
The sublimation and van der Waals (vdW) epitaxy on Bi 2 Se 3 (0001) surface have been first visualized using in situ reflection electron microscopy. When Bi 2 Se 3 (0001) surface was exposed to a Se molecular beam (up to 0.1 nm/s) and heated to ∼400°C, we observed ascending motion of atomic steps corresponding to congruent Bi 2 Se 3 sublimation. During the sublimation, grooves made by probe lithography act as sources of atomic steps: groove depth increases and generates atomic steps that move in the ascending direction away from the source. We used this phenomenon to create self-organized regularly-spaced zigzag atomic steps having 1 nm height on the Bi 2 Se 3 (0001) surface. The deposition of Bi (up to ∼0.01 nm/s) onto the Bi 2 Se 3 (0001) surface at constant Se flux (up to ∼0.1 nm/s) reversed the direction of the step flow, and vdW epitaxy was observed. The deposition of In and Se onto the Bi 2 Se 3 (0001) surface at ∼400°C led to the epitaxial growth of layered In 2 Se 3 . This vdW heteroepitaxy started with 2D island nucleation and, after 3–5 nm growth, continued with a screw-dislocation-driven formation of 3D islands. Ex situ Raman scattering measurements have shown that the grown 20-nm-thick In 2 Se 3 film exhibits vibrational modes that originate from the β-In 2 Se 3 crystal phase.