A method for producing a vertical semiconductor device includes providing a semiconductor substrate having a first surface and comprising an n-doped first semiconductor layer, forming a hard mask on the first surface, the hard mask comprising openings defining first zones in the n-doped first semiconductor layer, implanting acceptor ions of a first maximum energy through the hard mask into the first zones, replacing the hard mask by an inverted mask comprising openings that are substantially complementary to the openings of the hard mask; implanting acceptor ions of a second maximum energy different to the first maximum energy through the inverted mask into second zones of the n-doped first semiconductor layer, and carrying out at least one temperature step to activate the acceptor ions in the first zones and the second zones.