Simultaneous passivation and dissociation during the thermochemical interaction of trivalent interfacial Si traps (Si3=Si•) with molecular H was analyzed. A unified description was obtained by solving a set of simultaneous first-order rate equations which described passivation and dissociation. It was assumed here that the H2 concentrations at the interface and in the ambient were always equal. The analysis made allowance for the separate steps of passivation in H2 and dissociation in vacuum, and incorporated the existence of distinct spreads in the respective activation energies. The analysis, which was experimentally verified, showed that the Pb passivation level was not decreased (Pb regenerated) by successive annealing steps at gradually lower temperatures. The general inference was made that Pb could be easily passivated optimally (in 1atm of H2) to sub-1ppm levels.

Interaction of Pb Defects at the (111)Si/SiO2 Interface with Molecular Hydrogen: Simultaneous Action of Passivation and Dissociation. A.Stesmans: Journal of Applied Physics, 2000, 88[1], 489-97