Surface Science Letters Power law behavior in diVraction from fractal surfaces

The angular distribution of the diVraction intensity from a fractal surface is proportional to the power spectrum only when V%1, where V is equal to the square of the product of the interface width, w, and the momentum transfer perpendicular to the surface, k. However, it is shown that a power law behavior of the form k−2−2a d always exists in the large k d regime for all values of V, where a is the roughness exponent that is related to the surface fractal dimension Ds through a=3−Ds, and kd is the momentum transfer parallel to the surface. This power law behavior was confirmed in a light scattering experiment from a rough Si backside surface under diVerent diVraction conditions, i.e. diVerent