Low-temperature electrical studies on metal-oxide varistors—A clue to conduction mechanisms

Abstract
Current‐voltage data for metal‐oxide varistors are presented in the temperature range 4.2–420 °K. These results and other general observations concerning varistor behavior are used to help decide which of the several mechanisms employed to explain varistor conduction are indeed applicable. We conclude that a tunneling process is the only viable mechanism so far proposed to qualitatively describe conduction at breakdown.