Visible photoluminescence from silicon nanoconstrictions formed by heavy hydrogen implantation and annealing treatments

Ion implanted crystalline Si samples show luminescence (PL) in the visible at cryogenic temperatures after annealing treatments. This phenomenon is studied by varying the ion fluences and the sample doping density, and it is discussed considering the damage caused by the H implantation and its evolution with thermal treatments. A working hypothesis about the PL has been formulated which considers the exciton localisation in nanoconstrictions formed in the regions among the different microvoids produced by the implantation