The electroluminescence of SiO2 layers with excess silicon

We have studied the electroluminescence (EL) from Si-SiO2 structures containing excess ion-implanted silicon in the oxide layer. The implantation of 150-keV silicon ions to doses in the range from 5×1016 to 3×1017 cm−2 leads to the appearance of emission bands at 2.7 and 4.4 eV in the EL spectrum, which are usually assigned to the silylene centers. It is suggested that the formation of the corresponding emission centers is directly related to the ion implantation process, irrespective of the type of implanted ions.