As for Mechanism Simulation, there are three options:
This is the detailed simulation, thus it's called "fully" physical simulation. The energy distribution along the trajectory of every single energetic particle is simulated by Monte Carlo method, and the device response is simulated in charge carrier transport (TCAD device simulation).
Cogenda employs or develops professional methods to deal with the difficulties mentioned above, and thus has developed a sophisticated solution to fully physical simulation. Figure below shows the work-flow of the solution.
Figure below (left) gives a simulation example of a SRAM cell for SEU, a map for SEU event positions. Black squares are events that cause upsets, and round circles are non-upset events in which depth of color indicates tendency of upset. Simulation gives the exact sensitive area of the cell.
Figure below (right) gives the comparison between simulated results and experimental results of upset cross-section of a commercial SRAM.
NRED (Nuclear Reaction Energy Deposition) and NRED-MC do not use mask layout as device description method, but employ an artificially defined concept: Sensitive Volume (SV). The usage of SV is to replace TCAD simulation with a simple SEE criterion: If the electric charge produced by the particle within the SV exceeds a certain value (critical charge), the SEE will happen.
Compared with fully physical simulation, the pros and cons of NRED/NRED-MC are:
NRED/NRED-MC can also be used for Rate Prediction on orbits.