Autocovariance functions, root-mean-square-roughness height, and autocovariance length for rough deposits of copper, silver, and gold

Autocovariance functions (ACF's) for rough surfaces of Cu, Ag and Au deposits are deduced from surface profiles determined by the use of microdensitometer analysis of surface-shadowed carbon replicas. It is shown that the initial portions of the ACF's have a Gaussian form. The root-mean-square (rms) surface roughness delta and the autocorrelation length sigma are deduced for each surface. Values of sigma agree with corresponding values from the ACF's of the surface slopes. Results are compared with those previously obtained for rough Mg deposits. The Gaussian model is suitable to represent in general the ACF's of rough metallic surfaces. It is also shown that sigma increases with delta and, within the accuracy range of their measurements, there is a linear relation between delta and sigma . 20 ref.--AA