Chemisorbed CF3I on a Silicon Surface

  • Jason E. Sanabia
  • John H. Moore

Abstract

In plasma etching of silicon substrates, electron-impact on a halogen-containing feed gas creates chemically-active ions and radicals that react with silicon to form volatile SiXy (X = halogen) species. Unfortunately, the most widely-used feed gas, CF4, has a high global warming potential.1 As a consequence, other halocarbons are being considered as replacements for CF4. Trifluoroiodomethane, CF3I, is a promising candidate: It has a low global-warming potential2 and plasma-etching of silicon dioxide with CF3I has recently been demonstrated3-5.

Keywords

Dioxide Ozone Iodine Tungsten Iodide 

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Copyright information

© Springer Science+Business Media New York 2001

Authors and Affiliations

  • Jason E. Sanabia
    • 1
  • John H. Moore
    • 2
  1. 1.Chemical Physics ProgramUniversity of MarylandCollege ParkUSA
  2. 2.Department of Chemistry and BiochemistryUniversity of MarylandCollege ParkUSA

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