Impact of Si nanocrystals in a-SiOx〈Er〉 in C-band emission for applications in resonators structures

Si nanocrystals (Si-NC) in a-SiO_x<Er> were created by high temperature annealing. Si-NC samples have large emission in a broadband region, 700 nm to 1000 nm. Annealing temperature, annealing time, substrate type, and erbium concentration is studied to allow emission at 1550 nm for samples with erbium. Emission in the "C-band" region is largely reduced by the presence of Si-NC. This reduction may be due to less efficient energy transfer processes from the nanocrystals than from the amorphous matrix to the Er³⁺ ions, perhaps due to the formation of more centro-symmetric Er³⁺ sites at the nanocrystal surfaces or to very different optimal erbium concentrations between amorphous and crystallized samples.