Doping of silicon by phosphorus end-terminated polymers: shallow junction formation by thermal and laser annealing

Alternative approaches for doping of silicon have been the subject of an intense research activity to overcome the limitations of conventional doping techniques when applied to non-planar devices [1–4]. Recently, polymers terminated with a dopant containing moiety have been proposed as a viable solution for the doping of the new evolving 3D nanostructures [5]. The self-limiting nature of the grafting process of these molecules onto not deglazed Si surfaces has been widely investigated over the past few years, demonstrating the possibility to effectively control the concentration of P atoms on the sample surface [5, 6]. Additionally, high activation rate values (η a > 80%) were reported for this specific system upon drive-in of P atoms by conventional thermal treatments at high temperature in a standard RTP machine [7]. In this work, the possibility to combine this alternative doping technology with pulsed laser melting (PLM) is investigated, demonstrating the effective capability to form abrupt phosphorus junctions in silicon substrates.