(under subclass 487) Subject matter wherein the means for increasing breakdown voltage in the device includes a floating pn junction guard region, that is, a region, free of direct electrical connection, located in the material forming one side of an active pn or other rectifying semiconductor junction, which region forms a pn junction with the material of the one side of the active junction, the guard region being spaced from the active junction, but sufficiently close thereto that the reverse bias depletion region from the active junction can reach the guard junction, whereby the guard junction modifies the shape of the depletion region from the active junction thus lowering the electric field intensity at a given applied reverse voltage across the active junction.
