Chemical properties of oxidized silicon carbide surfaces upon etching in hydrofluoric acid

J Am Chem Soc. 2009 Nov 25;131(46):16808-13. doi: 10.1021/ja9053465.

Abstract

Hydrogen termination of oxidized silicon in hydrofluoric acid results from an etching process that is now well understood and accepted. This surface has become a standard for studies of surface science and an important component in silicon device processing for microelectronics, energy, and sensor applications. The present work shows that HF etching of oxidized silicon carbide (SiC) leads to a very different surface termination, whether the surface is carbon or silicon terminated. Specifically, the silicon carbide surfaces are hydrophilic with hydroxyl termination, resulting from the inability of HF to remove the last oxygen layer at the oxide/SiC interface. The final surface chemistry and stability critically depend on the crystal face and surface stoichiometry. These surface properties affect the ability to chemically functionalize the surface and therefore impact how SiC can be used for biomedical applications.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Carbon Compounds, Inorganic / chemistry*
  • Hydrofluoric Acid / chemistry*
  • Oxidation-Reduction
  • Photoelectron Spectroscopy
  • Silicon Compounds / chemistry*
  • Surface Properties

Substances

  • Carbon Compounds, Inorganic
  • Silicon Compounds
  • Hydrofluoric Acid
  • silicon carbide