Observation and characterization of periodic structure formation in dielectric breakdown channels of electron-irradiated polymethyl methacrylate
Abstract
Dielectric breakdown of insulators is a common failure mode in high-radiation environments and could be used for novel materials processing, but the mechanisms governing channel formation remain poorly understood. When electron-irradiated polymethyl methacrylate undergoes breakdown, the resulting channels exhibit striking periodic structures in the recently identified ivy-mode channels. Optical and electron microscopy revealed the presence of a boundary region that is also periodic, and Raman spectroscopy determined that carbon deposition correlates with channel width variations. We therefore conclude that the instability must occur during the plasma discharge phase. We systematically evaluated three candidate instability mechanisms and demonstrate that the z-pinch entropy mode governs the formation of periodic structures in the breakdown channels. This work represents, to our knowledge, the first direct observation of plasma instabilities creating persistent morphological features in solids. Our findings establish a predictive framework for discharge characteristics in insulators.
Article Details
Journal Info
Journal of Applied Physics
American Institute of Physics
Authors (14)
Nick R. Schwartz
Department of Materials Science and Engineering, University of Maryland 1 , College Park, Maryland 20742,
Bryson C. Clifford
Department of Materials Science and Engineering, University of Maryland 1 , College Park, Maryland 20742,
Carolyn Chun
Department of Materials Science and Engineering, University of Maryland 1 , College Park, Maryland 20742,
Emily H. Frashure
Department of Materials Science and Engineering, University of Maryland 1 , College Park, Maryland 20742,
Kathryn M. Sturge
Department of Materials Science and Engineering, University of Maryland 1 , College Park, Maryland 20742,
Noah Hoppis
Department of Materials Science and Engineering, University of Maryland 1 , College Park, Maryland 20742,
Holly Wilson
Department of Materials Science and Engineering, University of Maryland 1 , College Park, Maryland 20742,
Meryl Wiratmo
Department of Materials Science and Engineering, University of Maryland 1 , College Park, Maryland 20742,
Jack R. FitzGibbon
Department of Materials Science and Engineering, University of Maryland 1 , College Park, Maryland 20742,
Ethan T. Basinger
Department of Materials Science and Engineering, University of Maryland 1 , College Park, Maryland 20742,
Brian L. Beaudoin
Institute for Research in Electronics and Applied Physics, University of Maryland 2 , College Park, Maryland 20742,
Raymond J. Phaneuf
John Cumings
Timothy W. Koeth
Department of Materials Science and Engineering, University of Maryland 1 , College Park, Maryland 20742,