Room Temperature Light Emitting Diodes in Er-Doped Crystalline Si

In this work we report intense and sharp room temperature electroluminescence (EL) at 1.54 ¿m from Er and O co-doped crystalline Si p-n diodes fabricated by ion implantation. It is shown that Er luminescence can be electrically excited by electron-hole recombination under forward bias conditions and by impact excitation with hot electrons under reverse bias conditions. These two pumping mechanisms are characterized by a strikingly different temperature quenching of the EL intensity In fact, under forward bias, the EL yield decreases by a factor of 15 on going from 110 K to 300 K where a weak peak is still visible. In contrast, intense room temperature EL is obtained under reverse bias conditions in the breakdown regime. In this case the EL decrease by only a factor of 4 on going from 110 K to 300 K and the room temperature yield is more than one order of magnitude higher than under forward bias.