Shielded hydrogen passivation − A potential in‐line passivation process

Shielded hydrogen passivation (SHP) is a recently developed technique for introducing atomic hydrogen into materials and it offers significant advantages over the other hydrogenation techniques. Hydrogen de-activation of boron followed by electrochemical CV profiling was used to demonstrate that substantial quantities of atomic hydrogen can permeate though palladium/silver alloy foils which are 10 mu m thick. It is thought that such thickness will be sufficient to withstand pressures of up to 1 atmosphere allowing passivation in an in-line process. Further, it is shown that poisoning of the foil by using sulphur increases the flux of atomic hydrogen released. SHP delivers extremely good passivation of SiO2-Si interfaces, as demonstrated by using thermally oxidised 1 -cm, n-type silicon where the lifetime, at 10(15)cm(-3) injection level, was found to increase from 12 to 1.05ms after SHP processing. Upon application of corona charge, the lifetime further increased to 6.3ms, equivalent to SRV0.17cms(-1).