 The Poole–Frenkel effect describes how, in a large electric field, the electron doesn't need as much thermal energy to get into the conduction band (because part of this energy comes from being pulled by the electric field), so it does not need as large a thermal fluctuation and will be able to move more frequently.On theoretical grounds, the Poole-Frenkel effect is comparable to the Schottky effect, which is the lowering of the metal-insulator energy barrier due to the electrostatic interaction with the electric field at a metal-insulator interface.However, the conductivity arising from the Poole-Frenkel effect is detected in presence of bulk-limited conduction (when the limiting conduction process occurs in the bulk of a material), while the Schottky current is observed when the conductivity is contact-limited (when the limiting conduction mechanism occurs at the metal-insulator interface).