Luminescence of Er-implanted porous silicon

After Er+ ion implantation the bright visible emissions of porous silicon (PSi) still remain. After annealing 1.54μm characteristic emissions of Er3+ in PSi have been measured, and its intensity is much more intense than that of Si processed by same conditions. Further experiment shows that enhancement of the Er3+ emission relates to the surface layer of porous silicon. It is probable that the impurities introduced in surface layer by electrochemical process give rise to 1.54μm luminescence enhancement.