Title
Computational study of the <tex>$CF_{4}/CHF_{3}/H_{2}/Cl_{2}/O_{2}/HBr$</tex> gas phase plasma chemistry Computational study of the <tex>$CF_{4}/CHF_{3}/H_{2}/Cl_{2}/O_{2}/HBr$</tex> gas phase plasma chemistry
Author
Faculty/Department
Faculty of Sciences. Chemistry
Publication type
article
Publication
London ,
Subject
Physics
Chemistry
Source (journal)
Journal of physics: D: applied physics. - London
Volume/pages
49(2016) :19 , p. 1-19
ISSN
0022-3727
Article Reference
195203
Carrier
E-only publicatie
Target language
English (eng)
Full text (Publishers DOI)
Affiliation
University of Antwerp
Abstract
A modelling study is performed of high-density low-pressure inductively coupled CF4/CHF3/H2/Cl2/O2/HBr plasmas under different gas mixing ratios. A reaction set describing the complete plasma chemistry is presented and discussed. The gas fraction of each component in this mixture is varied to investigate the sensitivity of the plasma properties, like electron density, plasma potential and species densities, towards the gas mixing ratios. This research is of great interest for microelectronics applications because these gases are often combined in two (or more)-component mixtures, and mixing gases or changing the fraction of a gas can sometimes yield unwanted reaction products or unexpected changes in the overall plasma properties due to the increased chemical complexity of the system. Increasing the CF4 fraction produces more F atoms for chemical etching as expected, but also more prominently lowers the density of Cl atoms, resulting in an actual drop in the etch rate under certain conditions. Furthermore, CF4 decreases the free electron density when mixed with Cl2. However, depending on the other gas components, CF4 gas can also sometimes enhance free electron density. This is the case when HBr is added to the mixture. The addition of H2 to the gas mixture will lower the sputtering process, not only due to the lower overall positive ion density at higher H2 fractions, but also because more H+, $\text{H}_{2}
Full text (open access)
https://repository.uantwerpen.be/docman/irua/7563e4/132890.pdf
E-info
https://repository.uantwerpen.be/docman/iruaauth/e9f6c0/132890.pdf
Handle