Structural and electrical properties of metastable defects in hydrogenated amorphous silicon

Research output: Contribution to journalArticle

  • Authors:
  • J. Melskens
  • A. Schnegg
  • Amgalanbaatar Baldansuren
  • K. Lips
  • M. P. Plokker
  • And 5 others
  • External authors:
  • S. W H Eijt
  • H. Schut
  • M. Fischer
  • M. Zeman
  • A. H M Smets


The structural and electrical properties of metastable defects in various types of hydrogenated amorphous silicon have been studied using a powerful combination of continuous wave electron-paramagnetic resonance spectroscopy, electron spin echo (ESE) decay measurements, and Doppler broadening positron annihilation spectroscopy. The observed dependence of the paramagnetic defect density on the Doppler S parameter indicates that porous, nanosized void-rich materials exhibit higher spin densities, while dense, divacancy-dominated materials show smaller spin densities. However, after light soaking more similar spin densities are observed, indicating a long-term defect creation process in the Staebler-Wronski effect that does not depend on the a-Si:H nanostructure. From ESE decays it appears that there are fast and slowly relaxing defect types, which are linked to various defect configurations in small and large open volume deficiencies. A nanoscopic model for the creation of light-induced defects in the a-Si:H nanostructure is proposed.

Bibliographical metadata

Original languageEnglish
Article number245207
JournalPhysical Review B - Condensed Matter and Materials Physics
Issue number24
StatePublished - 11 Jun 2015