Current–voltage characteristic of alumina and aluminum nitride with or without electron irradiation

The current–voltage (I–V) characteristics of single- and poly-crystal alumina and aluminum nitride (AlN) were measured at temperatures ranging from room temperature to 723 K with or without 1 MeV electron irradiation in a high voltage electron microscope (HVEM). Both alumina and AlN specimens exhibit non-ohmic I–V characteristics without irradiation. The I–V characteristics in alumina, however, change from non-ohmic to almost ohmic under …