Characterization of near-interface traps at dielectric/SiC interfaces using CCDLTs

Isanka Jayawardhena, Asanka Jayawardena, Chunkun Jiao, Dallas Morisette, Sarit Dhar

Research output: Chapter in Book/Report/Conference proceedingConference PaperResearchpeer-review

Abstract

Charge trapping at 4H-SiC/dielectric interfaces in 4H-SiC MOS capacitors has been investigated using constant capacitance deep level transient spectroscopy (CCDLTS). The experiments were focused on further understanding of the following aspects related to 4H-SiC/SiO2 interfaces: (i) Origin of near interface oxide traps (NITs), (ii) Effect of interfacial impurity/passivation methods and (iii) Characterization of near-interface oxide traps for different SiC wafer orientations. For the (0001) Si-face 4H-SiC/ SiO2 interface, two types of NITs are typically detected by CCDLTS, named ‘O1’ and ‘O2’ traps with emission activation energies of about 0.15±0.05 eV and 0.39±0.1 eV respectively below the 4H-SiC conduction band. Based on comparison with previous ab initio calculations, the physical identities of these defects have been suggested to be carbon dimers substituted for O dimers (‘O1’) and interstitial silicon atoms (‘O2’) in the near interfacial SiO2 respectively. In this work, it is shown for the first time that such traps are not observed for 4H-SiC/ Al2O3 interfaces, proving that these traps are inherent to the near-interfacial SiO2. In addition, the summary of CCDLTS results for Si-face with different interface trap passivation methods are included in this study. Finally, a comparison is presented for NO annealed (0001) Si-face, (11-20) a face and (000-1) C-face interfaces that highlight the difference of CCDLTS signatures for the different crystal faces.

Original languageEnglish
Title of host publicationSilicon Carbide and Related Materials 2018
EditorsPeter M. Gammon, Vishal A. Shah, Richard A. McMahon, Michael R. Jennings, Oliver Vavasour, Philip A. Mawby, Faye Padfield
PublisherTrans Tech Publications
Pages217-221
Number of pages5
ISBN (Print)9783035713329
DOIs
Publication statusPublished - 1 Jul 2019
Externally publishedYes
EventEuropean Conference on Silicon Carbide and Related Materials 2018 - Birmingham, United Kingdom
Duration: 2 Sep 20186 Sep 2018

Publication series

NameMaterials Science Forum
Volume963
ISSN (Print)0255-5476
ISSN (Electronic)1662-9752

Conference

ConferenceEuropean Conference on Silicon Carbide and Related Materials 2018
CountryUnited Kingdom
CityBirmingham
Period2/09/186/09/18

Keywords

  • 4H-SiC
  • AlO
  • ALD
  • Constant capacitance deep level transient spectroscopy (CCDLTS)
  • Interface traps
  • MOS capacitors
  • Oxidation
  • Oxide traps
  • Passivation
  • SiO
  • Wafer orientation

Cite this

Jayawardhena, I., Jayawardena, A., Jiao, C., Morisette, D., & Dhar, S. (2019). Characterization of near-interface traps at dielectric/SiC interfaces using CCDLTs. In P. M. Gammon, V. A. Shah, R. A. McMahon, M. R. Jennings, O. Vavasour, P. A. Mawby, & F. Padfield (Eds.), Silicon Carbide and Related Materials 2018 (pp. 217-221). (Materials Science Forum; Vol. 963). Trans Tech Publications. https://doi.org/10.4028/www.scientific.net/MSF.963.217