A method for producing fin structures, using Directed Self Assembly (DSA) lithographic patterning, in an area of a semiconductor substrate includes providing a semiconductor substrate covered with a shallow trench isolation (STI) layer stack on a side thereof; defining a fin area on that side of the substrate by performing a lithographic patterning step other than DSA, wherein the fin structures will be produced in the fin area; and producing the fin structures in the semiconductor substrate within the fin area according to a predetermined fin pattern using DSA lithographic patterning. The disclosure also relates to associated semiconductor structures.