skip to main content

DOE PAGESDOE PAGES

Title: Anisotropic Etching of Hexagonal Boron Nitride and Graphene: Question of Edge Terminations

Here, chemical vapor deposition (CVD) has been established as the most effective way to grow large area two-dimensional materials. Direct study of the etching process can reveal subtleties of this competing with the growth reaction and thus provide the necessary details of the overall growth mechanism. Here we investigate hydrogen-induced etching of hBN and graphene and compare the results with the classical kinetic Wulff construction model. Formation of the anisotropically etched holes in the center of hBN and graphene single crystals was observed along with the changes in the crystals' circumference. We show that the edges of triangular holes in hBN crystals formed at regular etching conditions are parallel to B-terminated zigzags, opposite to the N-terminated zigzag edges of hBN triangular crystals. The morphology of the etched hBN holes is affected by a disbalance of the B/N ratio upon etching and can be shifted toward the anticipated from the Wulff model N-terminated zigzag by etching in a nitrogen buffer gas instead of a typical argon. For graphene, etched hexagonal holes are terminated by zigzag, while the crystal circumference is gradually changing from a pure zigzag to a slanted angle resulting in dodecagons.
Authors:
 [1] ; ORCiD logo [1] ; ORCiD logo [1] ; ORCiD logo [2] ;  [3] ; ORCiD logo [4] ; ORCiD logo [1]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  2. Univ. of Tennessee, Knoxville, TN (United States)
  3. National Renewable Energy Lab. (NREL), Golden, CO (United States)
  4. New Mexico State Univ., Las Cruces, NM (United States)
Publication Date:
Report Number(s):
NREL/JA-4A00-70577
Journal ID: ISSN 1530-6984; TRN: US1800178
Grant/Contract Number:
AC36-08GO28308
Type:
Accepted Manuscript
Journal Name:
Nano Letters
Additional Journal Information:
Journal Volume: 17; Journal Issue: 12; Journal ID: ISSN 1530-6984
Publisher:
American Chemical Society
Research Org:
National Renewable Energy Lab. (NREL), Golden, CO (United States); Energy Frontier Research Centers (EFRC) (United States). Fluid Interface Reactions, Structures and Transport Center (FIRST)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 2D materials; APCVD; boron nitride; edge termination; graphene; hBN; hydrogen etching
OSTI Identifier:
1411140

Stehle, Yijing Y., Sang, Xiahan, Unocic, Raymond R., Voylov, Dmitry, Jackson, Roderick K., Smirnov, Sergei, and Vlassiouk, Ivan. Anisotropic Etching of Hexagonal Boron Nitride and Graphene: Question of Edge Terminations. United States: N. p., Web. doi:10.1021/acs.nanolett.7b02841.
Stehle, Yijing Y., Sang, Xiahan, Unocic, Raymond R., Voylov, Dmitry, Jackson, Roderick K., Smirnov, Sergei, & Vlassiouk, Ivan. Anisotropic Etching of Hexagonal Boron Nitride and Graphene: Question of Edge Terminations. United States. doi:10.1021/acs.nanolett.7b02841.
Stehle, Yijing Y., Sang, Xiahan, Unocic, Raymond R., Voylov, Dmitry, Jackson, Roderick K., Smirnov, Sergei, and Vlassiouk, Ivan. 2017. "Anisotropic Etching of Hexagonal Boron Nitride and Graphene: Question of Edge Terminations". United States. doi:10.1021/acs.nanolett.7b02841. https://www.osti.gov/servlets/purl/1411140.
@article{osti_1411140,
title = {Anisotropic Etching of Hexagonal Boron Nitride and Graphene: Question of Edge Terminations},
author = {Stehle, Yijing Y. and Sang, Xiahan and Unocic, Raymond R. and Voylov, Dmitry and Jackson, Roderick K. and Smirnov, Sergei and Vlassiouk, Ivan},
abstractNote = {Here, chemical vapor deposition (CVD) has been established as the most effective way to grow large area two-dimensional materials. Direct study of the etching process can reveal subtleties of this competing with the growth reaction and thus provide the necessary details of the overall growth mechanism. Here we investigate hydrogen-induced etching of hBN and graphene and compare the results with the classical kinetic Wulff construction model. Formation of the anisotropically etched holes in the center of hBN and graphene single crystals was observed along with the changes in the crystals' circumference. We show that the edges of triangular holes in hBN crystals formed at regular etching conditions are parallel to B-terminated zigzags, opposite to the N-terminated zigzag edges of hBN triangular crystals. The morphology of the etched hBN holes is affected by a disbalance of the B/N ratio upon etching and can be shifted toward the anticipated from the Wulff model N-terminated zigzag by etching in a nitrogen buffer gas instead of a typical argon. For graphene, etched hexagonal holes are terminated by zigzag, while the crystal circumference is gradually changing from a pure zigzag to a slanted angle resulting in dodecagons.},
doi = {10.1021/acs.nanolett.7b02841},
journal = {Nano Letters},
number = 12,
volume = 17,
place = {United States},
year = {2017},
month = {11}
}