A test structure in accordance with the present invention allows for testing of both V.sub.bd TDDB, and leakage current between adjacent gate features. The test structure comprises a plurality of parallel polysilicon gate structures overlying a substrate. Traces placing alternate gates in electrical communication with a polysilicon edge are connected by a fuse. In one embodiment, a potential difference is applied across all gates to trigger V.sub.bd, and then the fuse is broken to allow individual probing of breakdown of the alternate groups of gates. In another embodiment, the fuse is broken and then force and sense voltages are applied to the edge polysilicon in communication with the alternate gate groupings, allowing detection of leakage current between the alternate groupings of gates that reveals the existence of an unwanted polysilicon extrusion or bridge.