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Title: Atomic state and characterization of nitrogen at the SiC/SiO{sub 2} interface

We report on the concentration, chemical bonding, and etching behavior of N at the SiC(0001)/SiO{sub 2} interface using photoemission, ion scattering, and computational modeling. For standard NO processing of a SiC MOSFET, a sub-monolayer of nitrogen is found in a thin inter-layer between the substrate and the gate oxide (SiO{sub 2}). Photoemission shows one main nitrogen related core-level peak with two broad, higher energy satellites. Comparison to theory indicates that the main peak is assigned to nitrogen bound with three silicon neighbors, with second nearest neighbors including carbon, nitrogen, and oxygen atoms. Surprisingly, N remains at the surface after the oxide was completely etched by a buffered HF solution. This is in striking contrast to the behavior of Si(100) undergoing the same etching process. We conclude that N is bound directly to the substrate SiC, or incorporated within the first layers of SiC, as opposed to bonding within the oxide network. These observations provide insights into the chemistry and function of N as an interface passivating additive in SiC MOSFETs.
Authors:
;  [1] ;  [2] ;  [1] ; ; ; ;  [1] ;  [2] ; ; ;  [3] ; ;  [4] ; ;  [5] ;  [6] ;  [1] ;  [2]
  1. Institute for Advanced Materials, Devices and Nanotechnology, Rutgers University, Piscataway, New Jersey 08854 (United States)
  2. (United States)
  3. Department of Physics, Auburn University, Auburn, Alabama 36849 (United States)
  4. Air Force Research Lab, Materials and Manufacturing Directorate, Wright-Patterson Air Force Base, Ohio 45433 (United States)
  5. Vanderbilt Institute of Nano-scale Science and Engineering, Vanderbilt University, Nashville, Tennessee 37235 (United States)
  6. Evans Analytical Group, East Windsor, New Jersey 08520 (United States)
Publication Date:
OSTI Identifier:
22275774
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 115; Journal Issue: 3; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; CARBON; CHEMICAL BONDS; COMPARATIVE EVALUATIONS; CONCENTRATION RATIO; ETCHING; INTERFACES; LAYERS; MOSFET; NITRIC OXIDE; NITROGEN; OXYGEN; PHOTOEMISSION; SILICON; SILICON CARBIDES; SILICON OXIDES; SUBSTRATES