Abstract:
The present invention relates to a method for creating nanostructures in and on organic or inorganic substrates comprising at least the following steps: a) providing a primary substrate having a predetermined refractive index; b) coating the primary substrate with one or more mediating layers each having a predetermined refractive index different from that of the primary substrate, wherein the sequence of the layers is arranged so that a predetermined gradient of the refractive index is generated between the primary substrate and the uppermost layer of the one or more mediating layers; c) optionally coating the uppermost layer of the one or more mediating layers with an additional top layer; d) depositing a nanostructured etching mask onto the uppermost layer of the composite substrate obtained after steps a)-b) or a) -c); e) generating protruding structures, in particular conical or pillar structures, or recessed structures, in particular holes, in at least the uppermost layer of the composite substrate by means of reactive ion etching. A further aspect of the invention relates to a composite substrate with a nanostructured surface obtainable by said method.