Scanning tunneling microscopy of buried dopants in silicon: images and their uncertainties

Published

August 23, 2022

Author(s)

Garnett W. Bryant, Piotr Rozanski, Michal Zielinski

Abstract

The ability to uniquely determine the locations of phosphorous dopants in silicon is crucial for the design and scaling of nanoscale devices for future quantum computing applications. In recent years, several papers showed that metrology combining scanning tunneling microscopy (STM) imaging with an atomistic tight-binding approach could be used to determine the exact coordinates of the dopant in the Si crystal. However, in this work, we demonstrate that such an approach may lead to a pronounced error bar for the determination of dopant depth. Moreover, for the same STM image as analyzed in previous work, we obtain a match with a tip orbital of dfferent symmetry. Additionally, we present a detailed study of various effects included in modeling of dopants and identify those which play a crucial role in the simulation, and have to be precisely accounted for in order for the multi-dopant metrology to work. Finally, we show that optimizing Slater orbitals' exponents is a key step to better agreement between simulated and experimental STM images.

Citation

npj Computational Materials

Volume

8

Issue

1

Pub Type

Journals

Download Paper

https://doi.org/10.1038/s41524-022-00857-w

Local Download

Keywords

scanning tunneling microscopy, imaging. silicon, dopants

Citation

Bryant, G. , Rozanski, P. and Zielinski, M. (2022), Scanning tunneling microscopy of buried dopants in silicon: images and their uncertainties, npj Computational Materials, [online], https://doi.org/10.1038/s41524-022-00857-w, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=933430 (Accessed April 28, 2024)