Electron spin resonance studies were carried out on the isothermal passivation kinetics in 1atm molecular H of trivalent Si traps (Si3 ≡ Si•) at the interface of thermal (111)/Si/SiO2 as a function of oxidation temperature Tox in the range 250–1100C. Interpretation within the generalized simple thermal passivation model, based on first-order interaction kinetics, revealed a distinct increase in spread of the activation energy for passivation, Ef, with decreasing Tox (about 3 times in the covered Tox window), while the other key kinetic parameters (Ef, pre-exponential factor) remained essentially unchanged. The variation in the spread of Ef was attributed to differently relaxed interfacial stress, affecting the spread in Pb defect morphology. In a second analytical part, the impact of the variation in Ef, and correlatively in the activation energy Ed for PbH dissociation, on Pb–H interaction kinetics was assessed within the generalized simple thermal-based full interaction scheme, describing parallel competing action of passivation and dissociation. In particular, the passivation behavior in 1atm H2 of an initially exhaustively de-passivated Pb system, was analyzed exposing, as a major result, that growing spreads of Ef and Ed resulted in a sharp reduction in the passivation efficiency (drop by 4 orders of magnitude for a threefold increase in the spread of Ef). At a proportional Ef spread of greater than 20%, the Pb system could not be inactivated beyond the 90% level, incompatible with device quality requirements. Heating time/temperature vs spread conditions for optimum passivation in H2 were established, and the technological impact of altering the spreads of Ef and Ed was considered. At film edges and trench corners, which were vulnerable local regions of excess stress, and hence enhanced spreads of Ef and Ed, an edge defeat effect with respect to passivation was revealed.Influence of Interface Relaxation on Passivation Kinetics in H2 of Coordination Pb Defects at the (111)Si/SiO2 Interface Revealed by Electron Spin Resonance. A.Stesmans: Journal of Applied Physics, 2002, 92[3], 1317-28