Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Effects of Nitrogen on the Interface Density of States Distribution in 4H-SiC Metal Oxide Semiconductor Field Effect Transistors: Super-hyperfine Interactions and Near Interface Silicon Vacancy Energy Levels

Published

Author(s)

Mark Anders, Patrick M. Lenahan, Arthur H. Edwards, Peter A. Schultz, Renee M. Van Ginhoven

Abstract

The performance of SiC-based metal-oxide-semiconductor field-effect transistors (MOSFETs) is greatly enhanced by a post oxidation anneal in NO. These anneals greatly improve effective channel mobilities and substantially decrease interface trap densities. In this work, we investigate the effect of NO anneals on the interface density of states though density functional theory calculations and electrically detected magnetic resonance (EDMR) measurements. EDMR measurements on 4H-SiC MOSFETs indicate that NO annealing substantially reduces the density of near interface SiC silicon vacancy centers: it results in a thirty-fold reduction in the EDMR amplitude. The anneal also alters post NO anneal resonance line shapes significantly. EDMR measurements exclusively sensitive to interface traps with near mid-gap energy levels have line shapes relatively unaffected by NO anneals whereas measurements sensitive to defects with energy levels more broadly distributed in the 4H-SiC band gap are significantly altered by the anneals. Using DFT, we show that the observed change in EDMR linewidth and the correlation with energy levels can be explained by nitrogen atoms introduced by the NO annealing substituting into nearby carbon sites of silicon vacancy defects.
Citation
Journal of Applied Physics
Volume
124
Issue
18

Keywords

SiC, silicon vacancy, nitrogen, defects, density of states

Citation

Anders, M. , Lenahan, P. , Edwards, A. , Schultz, P. and Van Ginhoven, R. (2018), Effects of Nitrogen on the Interface Density of States Distribution in 4H-SiC Metal Oxide Semiconductor Field Effect Transistors: Super-hyperfine Interactions and Near Interface Silicon Vacancy Energy Levels, Journal of Applied Physics, [online], https://doi.org/10.1063/1.5045668 (Accessed May 28, 2024)

Issues

If you have any questions about this publication or are having problems accessing it, please contact reflib@nist.gov.

Created November 13, 2018, Updated July 21, 2022