Abstract: An integrated circuit having multi-layer transistors which are separated from each other by means of tub-shaped or dish-shaped isolation zones. The isolation zones are of a conductivity type opposite to that of the zone of the circuit element which adjoins the inner wall of the tub-shaped zone and is present within the isolation zone, the p-n junction between the last-mentioned zone and the isolation zone being substantially short-circuited. As a result of this it is substantially prevented that the adjoining zone of the circuit element injects, via said p-n junction, charge carriers into the isolation zone, as a result of which the isolation is improved inter alia in that sense that the leakage current is reduced and higher breakdown voltages and smaller stray capacitances occur.