Efficent electroluminescence from Tb-implanted silicon metal-oxide-semiconductor devices

Strong green electroluminescence with brightness up to 2800 cd/m2 was obtained from indium-tin-oxide/SiO2:Tb/Si metal-oxide-semiconductor devices. The SiO2:Tb gate oxide was prepared by thermal oxidation followed by Tb+ implantation and annealing. Electroluminescence and photoluminescence properties were studied with variations of the Tb3+ ion concentration and annealing temperatures. The optimized device has a high external quantum efficiency of 16 % and a luminous efficiency of 2.1 lm/W. The excitation process of electroluminescence can be attributed to the impact excitation of the Tb3+ luminescent centers by hot electrons and the subsequent cross-relaxation from the 5D3 to 5D4 levels. Light emitting devices with micrometer size were demonstrated by the complementary metal-oxide-semiconductor technology.