This paper presents a process for the co-fabrication of self-aligned NMOS and single electron transistors made by gated polysilicon wires. The realization of SET–MOS hybrid architectures is also reported. The proposed process exploits an original low energy “hot” ion implantation for the doping of the 10 nm ultra-thin nano-grain polysilicon wire that serves for building the single electron transistors. Standard MOSFET characteristics and charge trapping, inducing hysteresis in the IDS–VGS characteristics of the polysilicon wires, are reported.