SIMULATION OF ELECTRONS IRRADIATION DAMAGES TO OPTIMIZE THE PERFORMANCE OF IGBT

Electron irradiation (IE) is a technique used to control the IGBT swit ching performances and then produce series of IGBT's with various swit ching velocities, However, this irradiation introduces undesirable eff ects on other parameters, such as forward voltage drop and leakage cur rent, In this paper, we propose a method to optimize the performances of the IGBT's considering the degradation effects. The IE effects are simulated using the two-dimensional device simulator ATLAS, Defects de nsities defined by their energy levels and capture cross section, and densities are introduced into all the structure layers. The energy lev els and capture cross sections are extracted from literature and densi ties are obtained by an iterative process, where the simulated charact eristics are fitted to the experimental ones, This method validity is confirmed by comparison of simulation results with experimental ones p erformed onto a series of IGBT's irradiated to various doses. Steady s tates and switching characteristics obtained by both simulation and me asurements are in good agreement and variations of forward voltage dro p versus turnoff time for various doses are obtained and used for perf ormance optimization purposes.