Charge transport in dielectrics by tunneling between traps

The theory of charge transport in dielectrics by tunneling between traps is developed. In contrast to the Frenkel model, traps in silicon nitride are characterized by two energies, optical and thermal ones, and ionization occurs by the multiphonon mechanism. The theory predicts that tunneling between such traps is thermally stimulated: the half-difference of the optical and thermal energies plays the role of the activation energy. This theory successfully explains the experimental current-voltage characteristics of silicon-enriched silicon nitride. Such silicon nitride contains a large number of traps whose nature is associated with excess silicon. Charge transport in this material occurs by tunneling between adjacent traps.