In an example, a first hard mask is formed on a first surface of a semiconductor body, wherein first openings in the first hard mask expose first surface sections and second openings in the first hard mask expose second surface sections. First dopants of a first conductivity type are implanted selectively through the first openings into the semiconductor body. Second dopants of a second conductivity type are implanted selectively through the second openings into the semiconductor body. The second conductivity type is complementary to the first conductivity type. A second hard mask is formed that covers the first surface sections and the second surface sections, wherein third openings in the second hard mask expose third surface sections and fourth openings in the second hard mask expose fourth surface sections. Third dopants of the first conductivity type are implanted selectively through the third openings into the semiconductor body. Fourth dopants of the second conductivity type are implanted selectively through the fourth openings into the semiconductor body.