Silicon-on-insulator microcavity light emitting diodes with two Si/SiO₂ Bragg reflectors

Light emitting pn-diodes were fabricated on a 5.8 µm thick n-type Si device layer of a silicon-on-insulator (SOI) wafer using standard silicon technology and boron implantation. The thickness of the Si device layer was reduced to 1.3 µm, corresponding to a 4λ-cavity for λ = 1150nm light. Electroluminescence spectra of these low Q-factor microcavities are presented. Addition of Si/SiO₂ Bragg reflectors on the top and bottom of the device (3.5 and 5.5 pairs, respectively) is predicted to lead to spectral emission enhancement by ∼270.