Electroluminescence in MOS structures with Si/SiO2 nanometric multilayers

Silicon light emitting devices, compatible with the conventional CMOS process, have been fabricated and tested. The structure of the devices is based on a MOS capacitor where nanometer thick silicon/silicon dioxide multilayers have been grown in the dielectric. Room temperature photo- and electroluminescence were measured. While photoluminescence has been recognized as being due to electron–hole recombination in the nanometer thick silicon layers, electroluminescence was mainly related to hot-electron relaxation in the substrate. The measured external quantum efficiency of the electroluminescence is about 5×10−5.