**6. Conclusion**

A new computational method for the simulation of single event effects in integrated circuits has been presented. This approach is a Monte Carlo method based on a random-walk driftdiffusion algorithm that transports the radiation-induced charge, segmented into discrete charge packets, in the semiconductor regions of a given circuit architecture. Carrier diffusion is very well reproduced with the random-walk algorithm while the carrier "drift" component of the model perfectly captures the effects of the electric field developed in the space-charge region of the reversely biased collecting contact(s). The model has been fully derived in C++ using advanced structures to model device/circuit geometry, particle track and charge transport, collection, recombination and extraction. This approach has been dynamically coupled with an internal subroutine or an external circuit simulator to take into account spatial and temporal variations of the electric field in the vicinity of the collecting structure(s). Thus, complex architectures, such as flip-flops, can be easily modeled and charge-sharing mecha‐ nisms are accurately simulated.

This chapter mainly focused on the model implementation and the way to solve the circuit response in the time domain, taking into account the circuit feedback on the charge collection process. Four simulation test cases have been explored and compared to radiation experiments or TCAD simulations in order to validate the proposed model. These test cases show good quantitative agreement between measurements and simulated data over a large range of LETs up to 60 MeV.cm2 /mg and structure complexity. This first implementation remains therefore not self-consistent with the electrostatic potential (in other words, Poisson's equation is not solved during the transient computation) and does not take into account the possible interac‐ tions between charge packets. The model ability to accurately reproduce a regime of high carrier injection is therefore uncertain. The limitations of the method will be more quantita‐ tively explored in a forthcoming dedicated study, as well as possible improvements in terms of self-consistency with the electrostatic problem.
