Deriving the exchange times for a model of trap-assisted tunnelling

The work presents a physical model of trap-assisted tunnelling that allows assessing the impact of traps upon the total current through metal/semiconductor heterostructures. The model is based on expressing the occupation probability of the trapping centres by electrons in terms of thermal and tunnelling capture and emission times, commonly referred to as exchange times. The occupation probabilities calculated in this way are then used to evaluate the generation-recombination rates occurring in the continuity equations.