Patent ID: 7763937

Claim:
A semiconductor device, comprising: a first region of a first conductivity type having a first portion extending to a first surface and a second portion spaced apart from the first surface; a second region of a second, opposite, conductivity type forming a first PN junction extending to the first surface with the first portion of the first region and a second PN junction with the second portion of the first region; a contact region of the second conductivity type in the second region at the first surface, spaced apart from the first PN junction by a first distance (L DS ); and a third region of the first conductivity type and of a second length (L BR ), underlying the second region and forming a third PN junction therewith and spaced apart from the first surface, wherein the third region has a portion located closer to the first PN junction than to the contact region, wherein the third region is non-uniformly doped along the second length.