A reflective optical mirror for semiconductor fabrication includes a
capping layer above a reflective multilayer sequence. A doping is
provided for the capping layer and an artificial oxide layer is grown on
the capping layer with the aid of hydrogen peroxide, in particular in the
presence of a catalyst. The artificially grown oxide layer is more
homogeneous than a naturally grown oxide and thereby improves optical
properties of the mirror during a lithographic exposure of semiconductor
products.