8 and 39). Two extreme recombination cross-sections were used: 10-16 cm 2 and 0. As can be seen, the recombination cross section, even at low values, is an essential parameter to field collapse and the trapped charge profile can be very different from the trap profile itself. [ um ] Figure 38. Charge collapse with code A in the V- Figure 39. Absence of charge collapse with code Model with e-h recombination purposely the V-Model with e-h recombination set at low value with pr=10-1 16 cm². switched off with pr=0 cm ². Field collapse in TRAPPOXR v.4 and code B operating in the J-Model Figure 40. Field collapse TRAPPOX in J-model (with recombination). III-57 Transistor Nmos Th-4500A Nd-1E17At/cm3 Nt-4.44E17At/cma D=5 krad E Field Y (V/cm) D=10 krad 800000 D=15 krad D=20 krad D-25 krad 800000 D=30 krad D-35 krad D=40 krad D=45 krad 400000 Figure 41. Field collapse D=50 krad D=100 krad with code B in D=150 krad the J-model. 200000 D-200 krad 200000 -400000 Mierona daide 450ml Trap denoity (4.4ddes-1) poss Baten le) sad/s, Insection-1e-12 effection-0 Transistor Nmos Th=4500A Timo-200s. knrappedcharge log g(pt[cm-31) Nd=1E17Aticm3 Nt=4.44E17Attcm3 Fixed Oxide Charge |/cm3 surre 0=5 krad 0=10 krad 0=15 krad 0-20 krad 0-25 krad 0=30 krad 0=35 krad 0-40 krad 0-45 krad 0=50 krad 0=100 krad 0-150 krad 0-200 krad Microns silicon 4-Brilla Instance I Code A in the V-model Code B in the J-model (lin scale) (log scale) Figure 42. Absence of charge collapse (without e-h recombination)with code A in the V-model and code B in the J-model. This code is used with the feature of ignoring the recombination of trapped holes by electron flux ( pr=0). In this case, it is clearly seen that field collapse occurs (FC) along with Field Enhancement (FE) at the interface regions, but not the charge collapse as for code A. GATE BIAS SWITCHING III-58 Bias switching is an important issue, as in real operational life, devices are operated in the dynamic mode where voltages are continuously varying. However, hardness assurance tests are most often per