Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Experiment Videos

Direct Evidence for Grain Boundary Potential Barrier Breakdown via In Situ Electron Holography.

Johnson1, Dravid

  • 1Department of Materials Science and Engineering, Northwestern University, 2225 N. Campus Drive, Evanston, IL 60208

Microscopy and Microanalysis : the Official Journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada
|November 30, 1999
PubMed
Summary

Researchers directly observed grain boundary potential barriers in a model varistor using high-resolution electron holography. They documented the barrier breakdown under current, explaining the varistor effect at the nanoscale.

Related Concept Videos

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Focused ion beam sample preparation of continuous fibre-reinforced ceramic composite specimens for transmission electron microscopy

Journal of microscopy·2000
Same author

Plasma Cleaning and Its Applications for Electron Microscopy.

Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada·1999
Same author

Chemical mediation of egg dumping in the lace bug Gargaphia solani Heidemann (Heteroptera: Tingidae).

Animal behaviour·1999
Same author

A Comparison of Streaming and Microelectrophoresis Methods for Obtaining the zeta Potential of Granular Porous Media Surfaces.

Journal of colloid and interface science·1999
Same author

Pleistocene extinction of genyornis newtoni: human impact on australian megafauna

Science (New York, N.Y.)·1999
Same author

Conditions for vigorous growth on sulfide and reactor-scale cultivation protocols for the thermophilic green sulfur bacterium chlorobium tepidum

Applied and environmental microbiology·1999

Area of Science:

  • Materials Science
  • Solid-State Physics
  • Electrical Engineering

Background:

  • Varistors exhibit nonlinear electrical behavior crucial for electronic circuit protection.
  • Grain boundaries in ceramic materials significantly influence their electrical properties.
  • Understanding potential barriers at grain boundaries is key to varistor performance.

Purpose of the Study:

  • To directly observe static and dynamic grain boundary potential barriers in a model varistor.
  • To investigate the mechanisms behind nonlinear electrical behavior in Nb-doped SrTiO3 bicrystals.
  • To correlate nanoscale barrier dynamics with macroscopic varistor effects.

Main Methods:

  • In situ high-resolution electron holography under applied current.
  • Electrical measurements on Nb-doped SrTiO3 bicrystals.

Related Experiment Videos

  • Analysis of grain boundary charge and space charge regions.

    • Main Results:

    • Direct visualization of a static positive grain boundary potential barrier (~0.45 V).
    • Observation of grain boundary barrier breakdown under high applied current.
    • Correlation between nanoscale barrier dynamics and bulk current-voltage (I-V) characteristics.

    Conclusions:

    • High-resolution electron holography can directly visualize grain boundary potential barriers.
    • The observed barrier breakdown mechanism explains the macroscopic varistor effect.
    • Nb-doped SrTiO3 bicrystals serve as a model system for understanding varistor physics.