Quantum Theory of Sputtering Rates in 2D Materials by Transmission Electron Microscopy

When and Where

Nov 28, 2023
9:00am - 9:30am

Hynes, Level 3, Ballroom B



Vincent Meunier1

Penn State University1


Vincent Meunier1

Penn State University1
Many computational models have been developed to predict the rates of atomic displacements in two-dimensional (2D) materials under electron beam irradiation. However, these models often drastically underestimate the displacement rates in 2D insulators, in which beam-induced electronic excitations can reduce the binding energies of the irradiated atoms. This bond softening leads to a qualitative disagreement between theory and experiment, in that substantial sputtering is experimentally observed at beam energies deemed far too small to drive atomic dislocation by many current models. To address these theoretical shortcomings, this paper develops a first-principles method to calculate the probability of beam-induced electronic excitations by coupling quantum electrodynamics (QED) scattering amplitudes to density functional theory (DFT) single-particle orbitals. The presented theory then explicitly considers the effect of these electronic excitations on the sputtering cross section. Applying this method to 2D hexagonal BN and MoS<sub>2</sub> significantly increases their calculated sputtering cross sections and correctly yields appreciable sputtering rates at beam energies previously predicted to leave the crystals intact. The proposed QED-DFT approach can be easily extended to describe a rich variety of beam-driven phenomena in any crystalline material.

Symposium Organizers

Gabriela Borin Barin, Empa
Shengxi Huang, Rice University
Yuxuan Cosmi Lin, TSMC Technology Inc
Lain-Jong Li, The University of Hong Kong

Symposium Support

Montana Instruments

Oxford Instruments WITec
Raith America, Inc.

Publishing Alliance

MRS publishes with Springer Nature


Symposium Support