Publication
Title
Modeling $Cl_{2}/O_{2}/Ar$ inductively coupled plasmas used for silicon etching : effects of $SiO_{2}$ chamber wall coating
Author
Abstract
 In this paper, simulations are performed to gain a better insight into the properties of a Cl2/Ar plasma, with and without O2, during plasma etching of Si. Both plasma and surface properties are calculated in a self-consistent manner. Special attention is paid to the behavior of etch products coming from the wafer or the walls, and how the chamber walls can affect the plasma and the resulting etch process. Two modeling cases are considered. In the first case, the reactor walls are defined as clean (Al2O3), whereas in the second case a SiO2 coating is introduced on the reactor walls before the etching process, so that oxygen will be sputtered from the walls and introduced into the plasma. For this reason, a detailed reaction set is presented for a Cl2/O2/Ar plasma containing etched species, as well as an extensive reaction set for surface processes, including physical and chemical sputtering, chemical etching and deposition processes. Density and flux profiles of various species are presented for a better understanding of the bulk plasma during the etching process. Detailed information is also given on the composition of the surfaces at various locations of the reactor, on the etch products in the plasma and on the surface loss probabilities of the plasma species at the walls, with different compositions. It is found that in the clean chamber, walls are mostly chlorinated (Al2Cl3), with a thin layer of etch products residing on the wall. In the coated chamber, an oxy-chloride layer is grown on the walls for a few nanometers during the etching process. The Cl atom wall loss probability is found to decrease significantly in the coated chamber, hence increasing the etch rate. SiCl2, SiCl4 and SiCl3 are found to be the main etch products in the plasma, with the fraction of SiCl2 being always slightly higher. The simulation results compare well with experimental data available from the literature.
Language
English
Source (journal)
Plasma sources science and technology / Institute of Physics. - Bristol, 1992, currens
Publication
Bristol : Institute of Physics, 2011
ISSN
0963-0252
Volume/pages
20:4(2011), p. 045012,1-045012,19
Article Reference
045012
ISI
000295829800014
Medium
E-only publicatie
Full text (Publishers DOI)
Full text (publishers version - intranet only)
UAntwerpen
 Faculty/Department Research group Publication type Subject Affiliation Publications with a UAntwerp address
External links
 Web of Science
Record
 Identification Creation 05.09.2011 Last edited 12.05.2017 To cite this reference