A process for producing structures in a semiconductor zone, has the steps of a) producing a trench (2) in the semiconductor zone (18), b) filling the trench with a photoresist (19), and c) exposing the photoresist (19) using ion beams (20), d) developing the photoresist (19). The energy density and ion dose for the ion beams (20) are selected in such a way that the photoresist (19) is only chemically changed at defined depths, so as to produce two regions, in the first region (21) of which the photoresist has been chemically changed at the defined depths by the ion beams (20), and in the second region of which the photoresist has been left chemically unchanged, so that during the developing step the photoresist is removed in precisely one of the two regions.