Temperature-Enhanced Low-Energy Ion Sputtering of Liquid Tin: Measurements and Modeling
Coventry, Matthew David
This item is only available for download by members of the University of Illinois community. Students, faculty, and staff at the U of I may log in with your NetID and password to view the item. If you are trying to access an Illinois-restricted dissertation or thesis, you can request a copy through your library's Inter-Library Loan office or purchase a copy directly from ProQuest.
Permalink
https://hdl.handle.net/2142/85910
Description
Title
Temperature-Enhanced Low-Energy Ion Sputtering of Liquid Tin: Measurements and Modeling
Author(s)
Coventry, Matthew David
Issue Date
2007
Doctoral Committee Chair(s)
Ruzic, David N.
Department of Study
Nuclear Engineering
Discipline
Nuclear Engineering
Degree Granting Institution
University of Illinois at Urbana-Champaign
Degree Name
Ph.D.
Degree Level
Dissertation
Keyword(s)
Engineering, Nuclear
Language
eng
Abstract
The potential for liquid Sn as a plasma-facing component in advanced thermonuclear fusion reactors and the observation of temperature-enhanced sputtering of Sn under low energy, light ion bombardment motivated further investigation of the temperature-dependent sputtering properties of Sn under various conditions. Experimental measurements using a well-characterized ion beam and a quartz-crystal microbalance (QCM) show that while the sputtering yield of Sn under 1000 eV He+ bombardment at 45° incidence increased from 0.33 +/- 0.14 to 0.80 +/- 0.24 atoms/ion due to increasing the sample temperature from 250°C to 575°C, cases where incident mass or energy were increased did not exhibit temperature dependence. Increasing the incident He+ energy to 2000 eV negated any temperature-dependencies as well as changing the incident species to Ne+ or Ar +. The mechanisms behind temperature enhanced sputtering are not clearly understood, but these data indicate that either the level of energy coupling between incident and target atoms or ion momentum could play a key role. Furthermore, molecular dynamics simulations provide evidence that the kinematics of the system have temperature dependent quantities that differ in the bulk than near ejected atoms. Implications on the use of liquid Sn as a divertor surface are addressed in addition to presentation of data and models.
Use this login method if you
don't
have an
@illinois.edu
email address.
(Oops, I do have one)
IDEALS migrated to a new platform on June 23, 2022. If you created
your account prior to this date, you will have to reset your password
using the forgot-password link below.
