Charge-transfer dipole moments at the Si-SiO2interface


Journal Article

A first-order model has been developed to calculate the magnitude of the dipole moment at the Si-SiO2interface resulting from partial charge transfer that takes place upon the formation of interface bonds. The charge transfer occurs because of the difference in electronegativity between the two species across the interface, namely silicon atoms and SiO2molecules. This approach is similar to that introduced to describe the modification of band lineup at the Si-SiO2interface by means of an intralayer of H or Cs. The charge-transfer estimation uses the principle of electronegativity equalization, and results obtained for (100) and (111) silicon substrates indicate that the magnitude of the interface dipole is orientation dependent. Dipole moments at the Si-SiO2and gate-SiO2interfaces should be included in the definition of the flatband voltage VFBof metal-oxide-semiconductor structures. The metal-semiconductor work function difference φmsdetermined from capacitance-voltage measurements on (100) and (111) silicon oxidized in dry oxygen and metallized with Al agree well in magnitude and sign with the predictions of this model. Other types of interface dipoles and their processing dependence will be examined.

Full Text

Duke Authors

Cited Authors

  • Massoud, HZ

Published Date

  • December 1, 1988

Published In

Volume / Issue

  • 63 / 6

Start / End Page

  • 2000 - 2005

International Standard Serial Number (ISSN)

  • 0021-8979

Digital Object Identifier (DOI)

  • 10.1063/1.341100

Citation Source

  • Scopus