Changes in the Poole-Frenkel coefficient with current induced defect band conductivity of hydrogenated amorphous silicon nitride

Shu Ping Lau, J. M. Shannon, B. J. Sealy

Research output: Journal article publicationJournal articleAcademic researchpeer-review

30 Citations (Scopus)

Abstract

Current induced conductivity in metal-semiconductor-metal thin film diodes containing hydrogenated amorphous silicon-rich alloys is determined by the concentration of silicon dangling bond states generated by the energy released during hole-electron recombination. This mechanism enables a range of defect concentrations to be introduced and results in a change in conductivity as carriers move between charged states in a defect band. Using a-SiNx:H with band gaps in the ranges 2.3 to 2.9 eV, we have measured the field dependence of the conductivity after stressing for increasing times and defect densities. By using the relationship between defect concentration and conductivity we have been able to establish that the apparent Poole-Frenkel coefficient (βPF) changes from βPFto 1/2βPFin a gradual way as the number of defects increase in a given material. Furthermore, in the transition region where βPFchanges from the classical to the anomalous value, βPFis linearly dependent on total number of defects.
Original languageEnglish
Pages (from-to)533-537
Number of pages5
JournalJournal of Non-Crystalline Solids
Volume227-230
Issue numberPART 1
DOIs
Publication statusPublished - 1 Jan 1998
Externally publishedYes

Keywords

  • Amorphous silicon nitride
  • Defects
  • Poole-Frenkel effect
  • Transport

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Ceramics and Composites
  • Condensed Matter Physics
  • Materials Chemistry

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