The effect of gold recombination centres on the trapping state at the Si-SiO2interface, and in the bulk, has been studied. The technique involves applying a linear voltage-ramp to the m.o.s. device and measuring the resultingI/Vcharacteristic. From the quasiequilibriumI/Vcurves, it is apparent that gold-doping produces a pronounced peak in the interfacial trap distribution occuring at energyEv+ 0.6eV with a density ofNss= 2.5 × 1011(cm2eV)−1. Subsequent non-steady-stateI/Vmeasurements are used to study the bulk recombination properties of gold, and thus determine a value for the capture cross-section (σp≃ 1.1 × 10−15cm2).