Ultrathin epitaxial Bi film growth on 2D HfTe2template

Evangelia Xenogiannopoulou; Dimitra Tsoutsou; Polychronis Tsipas; Sotirios Fragkos; Stefanos Chaitoglou; Nikolaos Kelaidis; Athanasios Dimoulas

doi:10.1088/1361-6528/ac2d08

Ultrathin epitaxial Bi film growth on 2D HfTe₂template

Nanotechnology. 2021 Oct 20;33(1). doi: 10.1088/1361-6528/ac2d08.

Authors

Evangelia Xenogiannopoulou¹, Dimitra Tsoutsou¹, Polychronis Tsipas¹, Sotirios Fragkos^{1

2}, Stefanos Chaitoglou¹, Nikolaos Kelaidis¹, Athanasios Dimoulas¹

Affiliations

¹ Institute of Nanoscience and Nanotechnology, National Center for Scientific Research 'Demokritos', 15310, Athens, Greece.
² Department of Mechanical Engineering, University of West Attica, 12244, Athens, Greece.

PMID: 34610589
DOI: 10.1088/1361-6528/ac2d08

Abstract

Among ultrathin monoelemental two-dimensional (2D) materials, bismuthene, the single layer of heavier group-VΑ element bismuth (Bi), has been predicted to have large non trivial gap. Here, we demonstrate the growth of Bi films by molecular beam epitaxy on 2D-HfTe₂template. At the initial stage of Bi deposition (1-2 bilayers, BL), both the pseudocubic Bi(110) and the hexagonal Bi(111) phases are formed. When reaching 3 BL Bi, a transformation to pure hexagonal Bi(111) occurs. The electronic band structure of 3 BL Bi(111) films was measured by angle-resolved photoemission spectroscopy showing very good matching with the density functional theory band structure calculations of 3 BL free standing Bi(111). The grown Bi(111) thin film was capped with a protective Al₂O₃layer and its stability under ambient conditions, necessary for practical applications and device fabrication, was confirmed by x-ray photoelectron spectroscopy and Raman spectroscopy.

Keywords: 2D heterostructures; ARPES; Bi; Xenes; ambient air stability; bismuthene; epitaxy.