A diode includes a first plurality of combo fins having lengthwise directions parallel to a first direction, wherein the first plurality of combo fins comprises portions of a first conductivity type. The diodes further includes a second plurality of combo fins having lengthwise directions parallel to the first direction, wherein the second plurality of combo fins includes portions of a second conductivity type opposite the first conductivity type. An isolation region is located between the first plurality of combo fins and the second plurality of combo fins. The first and the second plurality of combo fins form a cathode and an anode of the diode. The diode is configured to have a current flowing in a second direction perpendicular to the first direction, with the current flowing between the anode and the cathode.