Observations of very fast electron traps at SiC/high-κ dielectric interfaces
Journal article, 2023
Very fast interface traps have recently been suggested to be the main cause behind poor channel-carrier mobility in SiC metal-oxide-semiconductor field effect transistors. It has been hypothesized that the NI traps are defects located inside the SiO2 dielectric with energy levels close to the SiC conduction band edge and the observed conductance spectroscopy signal is a result of electron tunneling to and from these defects. Using aluminum nitride and aluminum oxide as gate dielectrics instead of SiO2, we detect NI traps at these SiC/dielectric interfaces as well. A detailed investigation of the NI trap density and behavior as a function of temperature is presented and discussed. Advanced scanning transmission electron microscopy in combination with electron energy loss spectroscopy reveals no SiO2 at the interfaces. This strongly suggests that the NI traps are related to the surface region of the SiC rather than being a property of the gate dielectric.
Author
Arnar M. Vidarsson
University of Iceland
A. R. Persson
Linköping University
J. T. Chen
Linköping University
SweGaN AB
Daniel Haasmann
Griffith University
J. Hassan
Linköping University
Sima Dimitrijev
Griffith University
Niklas Rorsman
Chalmers, Microtechnology and Nanoscience (MC2), Microwave Electronics
Vanya Darakchieva
Linköping University
Lund University
E. O. Sveinbjornsson
University of Iceland
Linköping University
APL Materials
2166-532X (eISSN)
Vol. 11 11 111121Center for III Nitride semiconductor technology (C3NiT) fas2
VINNOVA (2022-03139), 2022-11-21 -- 2027-12-31.
III-nitrider med låg defekttäthet för grön kraftelektronik
Swedish Foundation for Strategic Research (SSF) (EM16-0024), 2018-01-16 -- 2022-12-31.
Subject Categories
Other Electrical Engineering, Electronic Engineering, Information Engineering
Condensed Matter Physics
DOI
10.1063/5.0160287