Semiconductor structures and methods for suppressing latch-up in bulk CMOS devices. The semiconductor structure comprises first and second adjacent doped wells formed in the semiconductor material of a substrate. A trench, which includes a base and first sidewalls between the base and the top surface, is defined in the substrate between the first and second doped wells. The trench is partially filled with a conductor material that is electrically coupled with the first and second doped wells. Highly-doped conductive regions may be provided in the semiconductor material bordering the trench at a location adjacent to the conductive material in the trench.