Semiconductor device with a super junction structure based on a compensation structure with compensation layers and having a compensation rate gradient

A super junction semiconductor device comprising:

• a super junction structure formed in a semiconductor portion, wherein the super junction structure comprises a compensation structure comprising a first compensation layer of a first conductivity type and a second compensation layer of a complementary second conductivity type, the compensation structure lining at least sidewall portions of compensation trenches that extend between semiconductor mesas along a vertical direction perpendicular to a first surface of the semiconductor portion, wherein
• (i) in a first section of the super junction structure oriented to the first surface the second compensation layer includes a first sub-layer and a second sub-layer and, in a second section oriented to a second surface of the semiconductor portion parallel to the first surface, the second compensation layer comprises only the first sub-layer, and
• a sign of a lateral compensation rate changes along the vertical direction within the super junction structure, respectively.