According to one exemplary embodiment, a non-destructive method for determining a breakdown voltage of a dielectric layer on a semiconductor substrate includes injecting a test current in increasing ramp steps into the dielectric layer. The method further includes measuring a test voltage across the dielectric layer at each increasing ramp step of the test current. The method further includes detecting a dropped test voltage in response to the increasing ramp steps of the test current. The ramp steps of the test current can be substantially logarithmically increased. The breakdown voltage of the dielectric layer can be designated to be substantially equal to the dropped test voltage.