Growth Kinetics and Atomistic Mechanisms of Native Oxidation of ZrSxSe2- x and MoS2 Crystals

Seong Soon Jo; Akshay Singh; Liqiu Yang; Subodh C Tiwari; Sungwook Hong; Aravind Krishnamoorthy; Maria Gabriela Sales; Sean M Oliver; Joshua Fox; Randal L Cavalero; David W Snyder; Patrick M Vora; Stephen J McDonnell; Priya Vashishta; Rajiv K Kalia; Aiichiro Nakano; R Jaramillo

doi:10.1021/acs.nanolett.0c03263

Growth Kinetics and Atomistic Mechanisms of Native Oxidation of ZrS_xSe_{2- x} and MoS₂ Crystals

Nano Lett. 2020 Dec 9;20(12):8592-8599. doi: 10.1021/acs.nanolett.0c03263. Epub 2020 Nov 12.

Authors

Seong Soon Jo¹, Akshay Singh², Liqiu Yang³, Subodh C Tiwari³, Sungwook Hong⁴, Aravind Krishnamoorthy³, Maria Gabriela Sales⁵, Sean M Oliver^{6

7}, Joshua Fox⁸, Randal L Cavalero⁸, David W Snyder⁸, Patrick M Vora^{6

7}, Stephen J McDonnell⁵, Priya Vashishta³, Rajiv K Kalia³, Aiichiro Nakano³, R Jaramillo¹

Affiliations

¹ Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
² Department of Physics, Indian Institute of Science, Bengaluru, Karnataka 560012, India.
³ Collaboratory for Advanced Computing and Simulation, University of Southern California, Los Angeles, California 90089, United States.
⁴ Department of Physics and Engineering, California State University, Bakersfield, Bakersfield, California 93311, United States.
⁵ Department of Materials Science and Engineering, University of Virginia, Charlottesville, Virginia 22904, United States.
⁶ Department of Physics and Astronomy, George Mason University, Fairfax, Virginia 22030, United States.
⁷ Quantum Science and Engineering Center, George Mason University, Fairfax, Virginia 22030, United States.
⁸ Electronic Materials and Devices Department, Applied Research Laboratory and 2-Dimensional Crystal Consortium, Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, United States.

PMID: 33180506
DOI: 10.1021/acs.nanolett.0c03263

Abstract

A thorough understanding of native oxides is essential for designing semiconductor devices. Here, we report a study of the rate and mechanisms of spontaneous oxidation of bulk single crystals of ZrS_xSe_2-x alloys and MoS₂. ZrS_xSe_2-x alloys oxidize rapidly, and the oxidation rate increases with Se content. Oxidation of basal surfaces is initiated by favorable O₂ adsorption and proceeds by a mechanism of Zr-O bond switching, that collapses the van der Waals gaps, and is facilitated by progressive redox transitions of the chalcogen. The rate-limiting process is the formation and out-diffusion of SO₂. In contrast, MoS₂ basal surfaces are stable due to unfavorable oxygen adsorption. Our results provide insight and quantitative guidance for designing and processing semiconductor devices based on ZrS_xSe_2-x and MoS₂ and identify the atomistic-scale mechanisms of bonding and phase transformations in layered materials with competing anions.

Keywords: Kinetics; Native oxidation; Reactive molecular dynamics simulations; ReaxFF reactive force field; Spectroscopic ellipsometry; Transition metal dichalcogenides.