Influence of particle oxide coating on light scattering by submicron metal particles on silicon wafers

We report the effect of room-temperature oxidation on scattering of 633 nm light by copper particles deposited on a silicon wafer. The results provide a validation for a theory of light scattering by coated particles on a substrate and establish the lifetime of these particles as light scattering standards to be on the order of a few months. The results also suggest that the room-temperature oxidation of copper particles proceeds in a continuous manner, rather than approaching an asymptotic thickness as found by Cabrera and Mott [Rep. Prog. Phys. 12, 163 (1948)] on copper films. (C) 2004 American Institute of Physics.