High electron mobility due to sodium ions in the gate oxide of SiC-metal-oxide-semiconductor field-effect transistors

B. R. Tuttle, S. Dhar, S. H. Ryu, X. Zhu, J. R. Williams, L. C. Feldman, S. T. Pantelides

Research output: Contribution to journalArticle

19 Citations (Scopus)


Oxidation of SiC with the incorporation of Na in the gate oxide was recently found to lead to significantly enhanced electron mobilities in the SiC inversion layer but the underlying mechanism has remained elusive. Here, we report a combination of density functional first-principles calculations and experiments. The new findings demonstrate that neutral Na is essentially a spectator impurity that occupies near interfacial interstitial sites and does not interact with the interface or with interfacial defects. Na ions, however, introduce an effective mass hydrogenic impurity band at the edge of the SiC conduction band that can account for the observed effects.

Original languageEnglish
Article number023702
JournalJournal of Applied Physics
Issue number2
Publication statusPublished - Jan 15 2011


ASJC Scopus subject areas

  • Physics and Astronomy(all)

Cite this