Interfacial absorption of DUV coatings

Complicated dielectric coatings consist of a large number of layers and thus have many interfaces, that may contribute to the total absorption of the coatings. We examined this contribution of the interfaces using two different approaches. For the determination of the absorption of the first interface between the substrate and the coatings we varied the thickness of dielectric single layers. For the examination of the influence of the interfaces within a dielectric stack, coatings consisting of (lambda) /2-layers were produced and their absorption was measured.