Use of multiple slots surrounding base region of a bipolar junction transistor to increase cumulative breakdown voltage

摘要

A semiconductor device having the base region surrounded by at least two continuous slots. The collector region is surrounded by at least one continuous slot formed as a continuation of one of the at least two continuous slots surrounding the base region. The portions of the slots that are over the buried layer extends beyond the surface of the buried layer and the portions of the slots not over the buried layer extends beyond the interface between the epitaxial layer and the substrate. The slots are filled with either polysilicon or tungsten. The base region terminates on the surface of the innermost slot surrounding the base region. The boundary of the base region terminates substantially perpendicular to the surface of the surrounding slot.