Strong visible electroluminescence from Ge- and Sn-implanted silicon dioxide layers

Silicon-based light emission is a key feature to make a real step into the world of integrated optical systems, laboratory-on-chip applications and high performance optical communication. One of the most promising approaches is ion implantation into thin SiO2 films. In this paper, the electroluminescence (EL) properties of Sn-implanted SiO2 layers are investigated and compared with those of Ge-implanted SiO2 layers. Strong EL in the blue-violet spectral region with a power efficiency of 0.025% is extracted from Sn-implanted oxide layers. Similar to the case of Ge, the main emission at 3.2 eV is attributed to a radiative T1→S0 transition of an Sn-related oxygen deficiency center, the EL intensity increases linearly over several orders of magnitude and the stability reaches comparable values. In contrast to the case of Ge, a low-energy shoulder appears in the EL spectrum of Sn-implanted oxides. Finally, the suitability of Sn-implanted oxides for optoelectronic applications is discussed.