A method is provided which includes forming a hardmask feature adjacent to a patterned sacrificial structure of a semiconductor topography, selectively removing the patterned sacrificial structure to expose a lower layer and etching exposed portions of the lower layer in alignment with the hardmask feature. Here it is essential that the air supply line, at least with its end segment connected to the mixing chamber, can be selectively connected via a valve to a line having rinsing medium. In an embodiment, protection mechanisms that offer a higher level of protection are selected for the more popular content elements and protection mechanisms that offer a lower level of protection are selected for the less popular content elements.