Breakdown in a MOSFET
Application ID: 15583
MOSFETs typically operate in three regimes depending on the drain-source voltage for a given gate voltage. Initially the current-voltage relation is linear, this is the Ohmic region. As the drain-source voltage increases the extracted current begins to saturate, this is the saturation region. As the drain-source voltage is further increased the breakdown region is entered, where the current increases exponentially for a small increase in the applied voltage. This is due to impact ionization.
This model shows how to use the time dependent solver to model impact ionization in a MOSFET.