MEASUREMENTS AND SIMULATION OF AVALANCHE BREAKDOWN IN ADVANCED Si BIPOLAR TRANSISTORS

A complete analytical model for impact ionization effects in bipolar transistors, which is able to predict the behaviour of advanced devices up to breakdown, is presented. A simple expression of the carrier mean energy suitable for circuit simulation is used to calculate the device multiplication coefficient and enables the influence of non-equilibrium transport on impact ionization to be accounted for. The role played by the reverse base current in determining the snapback of the common base output characteristics is investigated both experimentally and theoretically.