 In a charge trapping flash, electrons are stored in a trapping layer just as they are stored in the floating gate in a standard flash memory, EEPROM, or EPROM.The key difference is that the charge trapping layer is an insulator, while the floating gate is a conductor.High write loads in a flash memory cause stress on the tunnel oxide layer creating small disruptions in the crystal lattice called “oxide defects.” If a large number of such disruptions are created a short circuit develops between the floating gate and the transistor's channel and the floating gate can no longer hold a charge.