Threshold-voltage instability caused by the hot-carrier substrate current in MOSFETs

The need for precise modelling and evaluation of the threshold-voltage shift and instability in ultra-short channel MOSFETs has increased considerably, due to advances in technology and the introduction of novel high-complexity applications. The hot carrier substrate current is shown to be one of the most important parameters which appreciably shifts the threshold voltage and affects its instability. Two analytical models are considered, one for predicting the hot-carrier substrate current and the other to evaluate the threshold-voltage shift and investigate its dependence on the current level and the device's mode of operation.