Meaning
Quantum mechanical process where electrons tunnel through a thin dielectric layer under the influence of a high electric field. Measuring fowler nordheim emission identifies the quality of insulating oxides in non-volatile memory devices. This mechanism allows for the programming and erasing of flash memory cells by moving charge across an energy barrier.
Field Induction
High voltage applied across the gate oxide narrows the potential barrier for electrons. The fowler nordheim emission occurs when the electric field strength reaches the level required for tunneling to become significant. This current is exponentially dependent on the field intensity and the thickness of the oxide layer.
Carrier Transport
Electrons pass from the silicon substrate into the floating gate to change the threshold voltage of the transistor. An accurate model of fowler nordheim emission accounts for the effective mass of the electrons and the height of the energy barrier at the interface. This transport is the primary method for modifying the data state in floating-gate transistors.
Barrier Degradation
Repeated tunneling cycles create defects in the dielectric lattice. The fowler nordheim emission characteristics change as the oxide traps charges, which eventually leads to the failure of the memory cell. Testing these levels during the manufacturing process ensures that the device meets its rated endurance specifications.
