Atomic scale characterization of SiO2/4H-SiC interfaces in MOSFETs devices

Anna Maria Beltrán (1, 2) , Sébastien Duguay (3) , Christian Strenger (4) , Anton J Bauer (4) , Fuccio Cristiano (5) , Sylvie Schamm-Chardon (1, 6)

1 CEMES - Centre d'élaboration de matériaux et d'études structurales
2 LAAS - Laboratoire d'analyse et d'architecture des systèmes
3 GPM - Groupe de physique des matériaux
4 Fraunhofer IISB - Fraunhofer Institute for Integrated Systems and Device Technology
5 LAAS-MPN - Équipe Matériaux et Procédés pour la Nanoélectronique
6 CEMES-MEM - Matériaux et dispositifs pour l'Electronique et le Magnétisme

The breakthrough of 4H-SiC MOSFETs is stemmed mainly due to the mobility degradation in their channel in spite of the good physical intrinsic material properties. Here, two different n-channel 4H-SiC MOSFETs are characterized in order to analyze the elemental composition at the SiC/SiO2 interface and its relationship to their electrical properties. Elemental distribution analyses performed by EELS reveal the existence of a transition layer between the SiC and the SiO2 regions of the same width for both MOSFETs despite a factor of nearly two between their electron mobility. Additional 3D compositional mapping by atom probe tomography corroborates these results, particularly the absence of an anomalous carbon distribution around the SiC/SiO2 interface. © 2015 Elsevier Ltd. All rights reserved.

Keywords: 4h-sic mosfets; Elemental compositions; Compositional mapping; Carbon; Silicon carbide; Transition layers; MOSFET devices; Mobility degradation; Carbon distribution; Atom probe tomography; Elemental distribution; Electron energy loss spectroscopy

Domains: Physics [physics]; Materials Science [cond-mat.mtrl-sci]

Anna Maria Beltrán, Sébastien Duguay, Christian Strenger, Anton J Bauer, Fuccio Cristiano, et al.. Atomic scale characterization of SiO2/4H-SiC interfaces in MOSFETs devices. Solid State Communications, 2015, 221, pp.28-32. ⟨10.1016/j.ssc.2015.08.017⟩. ⟨hal-01720451⟩