Potential fluctuations due to P_b centres at the Si/SiO₂ interface

We show that the potential fluctuation model of Brews applies very accurately to Pb centres at the (111) and (100) interfaces. Vacuum annealed MOS samples were used which contained a particularly 'pure' interface largely dominated by the Pb-like defects. For the (100) interface, Pb0 and Pb1 defects appear to have the same capture cross-section.