A two-dimensional numerical simulation of oxide charge buildup in MOS transistors due to radiation

Abstract

The authors have developed a time-dependent two-dimensional simulator in order to simulate charge trapping in silicon dioxide due to radiation. The Poisson and continuity equations are solved both in the oxide and the semiconductor. In addition, in order to simulate charge trapping, trap rate equations using first-order trapping kinetics are solved in the oxide. This paper contains the numerical methods used in the simulation and results obtained using this simulator. One of the main results of this simulation is the presence of a lateral variation in the radiation-induced oxide charge in an MOS transistor irradiated with a drain bias.