A heat sink for semiconductor components or similar devices, especially produced from an extruded aluminum alloy. The heat sink comprises cooling ribs which rise at a distance from a base plate and which are clamped in an insert groove made in the surface of the base plate, laterally limited by longitudinal or intermediate ribs with a coupling base that has an approximately rectangular cross-section. The coupling bases are held in their insert grooves in a form-fit and are cold-welded with the base plate at least in some sections. Cross ribs extend at a distance to one another on the surfaces of the intermediate ribs and have the form of upset heels that are linked with the coupling base in a form-fit.