Formation of Si-based light-emitting structures by ion implantation and pulsed treatments

The creation of Si-based light-emitting structures by continuous ion implantation and nanosecond pulsed annealing is reviewed by the example of Si:Er and ß-FeSi₂ layers. These layers are promising for optoelectronics due to the light emission in the 1.5-1.6 ¿m communication range. Si:Er and ß-FeSi₂ layers were formed by Er⁺ or Fe⁺ implantation into Si(100) wafers followed by pulsed annealing with high-power ion beams. The structural and optical properties of the implanted and annealed Si layers were studied by TEM, RBS and PL methods. TEM and RBS measurements showed the similarity in the microstructure of the annealed Si layers and the depth distribution of Fe and Er atoms in Si. PL measurements at 77 K demonstrated the intense PL peaks at ¿ = 1.5-1.6 ¿m. For the first time, a triple Si/ß-FeSi₂/Si heterostructure was fabricated by the combination of ion implantation, pulsed annealing and molecular-beam epitaxy of Si epilayer. PL measurements of the Si/ß-FeSi₂/Si heterostructure at 5 K showed that the light emission at ¿ = 1.4-1.7 ¿m is due to the contributions from ß-FeSi₂ precipitates and dislocations.