Er-doped polycrystalline silicon for light emission at λ=1.54 µm

Abstract

We deposited amorphous silicon films, implanted them with erbium/oxygen, and then recrystallized them with a series of thermal treatments. Recrystallization is necessary to remove implantation damage and optically activate Er/O complexes for light emission at 1.54 µm. Photoluminescence and glancing angle x-ray diffraction were used to characterize the polycrystalline Si:Er. Following 30-minute isochronal anneals and isothermal anneals at 575°C and 600°C, the erbium luminescence intensity was observed to increase in direct relation to the degree of recrystallization during the anneal. Hydrogen passivation of dangling bonds further increased the luminescence intensity to about one half of the intensity found in a comparable single crystal material. The optically active Er is shown to be located within the recrystallized grains, and it exhibits a de-excitation (backtransfer) mechanism similar to that of single crystal Si:Er.