The conduction characteristics of the inversion channel of Si-transistor structures after the ionic polarization and depolarization of samples are measured in (0–5)-T transverse magnetic fields at temperatures from 100 to 200 K. After ionic polarization in a strong electric field at 420 K, no less than 6 × 1013 cm–2 ions flowed through the oxide. The previously found tenfold increase in the conductivity in the source–drain circuit after the polarization of insulating layers is explained by the formation of a new electron transport path along the surface impurity band, related to delocalized D– states; these states are generated by neutralized ions located in the insulating layer at its interface with the semiconductor.