The invention provides a capping technology in which, despite the fact that the structures (2) which are surrounded by a silicon/germanium filling layer (4, 3) are exposed using ClF3 etching through micropores in the silicon capping (7), an etching attack on the silicon cap (7, 11) is prevented in this process, namely either by particularly selective (for instance 10000:1 or higher) setting of the etching process itself or by using the knowledge that the oxide of a germanium-rich layer (5, 10), in contrast to the oxidized porous silicon (11), is not stable but rather can be easily detached to protect the silicon cap (7, 11).