重新审视在不同衬底上生长（BiSb）Te薄膜时的范德华外延。

Revisiting the van der Waals Epitaxy in the Case of (BiSb)Te Thin Films on Dissimilar Substrates.

作者信息

Mulder Liesbeth, Wielens Daan H, Birkhölzer Yorick A, Brinkman Alexander, Concepción Omar

机构信息

MESA+ Institute for Nanotechnology, University of Twente, 7500 AE Enschede, The Netherlands.

出版信息

Nanomaterials (Basel). 2022 May 24;12(11):1790. doi: 10.3390/nano12111790.

DOI:10.3390/nano12111790

PMID:35683648

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC9181916/

Abstract

Ultrathin films of the ternary topological insulator (Bi0.4Sb0.6)2Te3 are fabricated by molecular beam epitaxy. Although it is generally assumed that the ternary topological insulator tellurides grow by van der Waals epitaxy, our results show that the influence of the substrate is substantial and governs the formation of defects, mosaicity, and twin domains. For this comparative study, InP (111)A, Al2O3 (001), and SrTiO3 (111) substrates were selected. While the films deposited on lattice-matched InP (111)A show van der Waals epitaxial relations, our results point to a quasi-van der Waals epitaxy for the films grown on substrates with a larger lattice mismatch.

摘要

通过分子束外延法制备了三元拓扑绝缘体（Bi0.4Sb0.6）2Te3的超薄膜。尽管通常认为三元拓扑绝缘体碲化物通过范德华外延生长，但我们的结果表明，衬底的影响很大，并且控制着缺陷、镶嵌性和孪晶畴的形成。为了进行这项对比研究，选择了InP（111）A、Al2O3（001）和SrTiO3（111）衬底。虽然沉积在晶格匹配的InP（111）A上的薄膜显示出范德华外延关系，但我们的结果表明，在晶格失配较大的衬底上生长的薄膜为准范德华外延。