Temporal Evolution of Surface Contamination under Ultra-high Vacuum
Name
_Temporal Evolution of Surface Contamination Under Ultra-High Vacuum.pdf
Description
Accepted version
Size
428.94 KB
Format
Unknown
Checksum (MD5)
30409f7be6077599ebd4cb2c1f974184
Author(s)
Liu, Zhen
Song, Youngsup
Rajappan, Anoop
Wang, Evelyn N.
Preston, Daniel J.
Date Issued
January 2022
Journal
Langmuir
Publisher
American Chemical Society (ACS)
Citation
Liu, Zhen, Song, Youngsup, Rajappan, Anoop, Wang, Evelyn N and Preston, Daniel J. 2022. "Temporal Evolution of Surface Contamination under Ultra-high Vacuum." Langmuir, 38 (3).
Version
Author's final manuscript
Abstract
Ultra-high vacuum (UHV) is essential to many surface characterization techniques and is often applied with the intention of reducing exposure to airborne contaminants. Surface contamination under UHV is not well-understood, however, and introduces uncertainty in surface elemental characterization or hinders surface-sensitive manufacturing approaches. In this work, we investigated the time-dependent surface composition of gold samples with different initial levels of contamination under UHV over a period of 24 h with both experiments and physical modeling. Our results show that surface hydrocarbon concentration under UHV can be explained by molecular adsorption-desorption competition theory. Gold surfaces that were initially pristine adsorbed hydrocarbons over time under UHV; conversely, surfaces that were initially heavily contaminated desorbed hydrocarbons over time. During both adsorption and desorption, the concentration of contaminants tended toward the same equilibrium value. This study provides a comprehensive evaluation of the temporal evolution of surface contamination under UHV and highlights routes to mitigate surface contamination effects.
MIT Department
Massachusetts Institute of Technology. Department of Mechanical Engineering
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1021/acs.langmuir.1c03062
