Concentration, chemical bonding, and etching behavior of P and N at the SiO2/SiC(0001) interface

Abstract

Phosphorous and nitrogen are electrically active species at the SiO2/SiC interface in SiC MOSFETs. We compare the concentration, chemical bonding, and etching behavior of P and N at the SiO2/SiC(0001) interface using photoemission, ion scattering, and secondary ion mass spectrometry. Both interfacial P and N are found to be resistant to buffered HF solution etching at the SiO2/SiC(0001) interface while both are completely removed from the SiO2/Si interface. The medium energy ion scattering results of etched phosphosilicate glass/SiC not only provide an accurate coverage but also indicate that both the passivating nitrogen and phosphorus are confined to within 0.5 nm of the interface. Angle resolved photoemission shows that P and N are likely situated in different chemical environments at the interface. We conclude that N is primarily bound to Si atoms at the interface while P is primarily bound to O and possibly to Si or C. Different interface passivating element coverages and bonding configurations on different SiC crystal faces are also discussed. The study provides insights into the mechanisms by which P and N passivate the SiO2/SiC(0001) interface and hence improve the performance of SiC MOSFETs.

Document Details

Document Type
Pub Defense Publication
Publication Date
Dec 17, 2015
Source ID
10.1063/1.4937400

Entities

People

  • A. C. Ahyi
  • A. Modic
  • A. Wan
  • C. Jiao
  • Can Xu
  • E. L. Garfunkel
  • G. Liu
  • H. D. Lee
  • Jason Williams
  • L. C. Feldman
  • S. M. Shubeita
  • Shilpa S. Dhar
  • T. Gustafsson
  • Yan Xu
  • Yogesh K. Sharma

Organizations

  • Auburn University
  • National Science Foundation
  • Rutgers University
  • United States Army Research Laboratory

Tags

Readers

  • Electrochemical Engineering/ Fuel Cell Technologies
  • Semiconductor Device Technology