MODELING OF THE HOT-ELECTRON SUBPOPULATION AND ITS APPLICATION TO IMPACT IONIZATION IN SUBMICRON SILICON DEVICES .1. TRANSPORT-EQUATIONS

Impact ionization (II) in three different n+ - n- - n+ device structur es is investigated using self-consistent Monte Carlo simulations. A su bset of electrons participating in II-referred to as the hot electron subpopulation (HES)-is identified. The data obtained from the Monte Ca rlo (MC) simulations indicate that the average energy of the HES (w) i s an appropriate variable for the macroscopic quantification of II in all the devices under consideration. In order to calculate w, a set of macroscopic transport equations for the HES is derived from the Boltz mann transport equation and calibrated using data from the MC simulati ons. Numerical solutions to the proposed II model applied to the three devices considered here will be presented in Part II. Therein, values of the II coefficient (IIC) predicted by our model will be compared t o those obtained from our MC simulations and also to IIC values predic ted bv models proposed earlier by other authors.