Luminescence properties of Bi-doped oxidized porous silicon thin films

Luminescence properties of Bi-doped oxidized porous silicon (OPS) thin films were studied. It was found that this material shows two broad luminescence bands centered at 845 nm with the FWHM of 120 nm and at 1410 nm with that of 220 nm under 488 nm excitation. A detailed analysis of the 3D plot of PL intensities versus excitation and emission wavelengths revealed that these luminescence bands arise from at least two different kinds of Bi luminescence centers. The broad luminescence covering the whole telecommunication window (1.2–1.6 μm) suggests that Bi-doped OPS thin films can be a candidate material for a broadband waveguide-type optical amplifier at optical telecommunication wavelengths.

► PL properties of Bi-doped oxidized porous silicon were reported for the first time.
► The samples were prepared by anodizing etching of Si wafer and dip coating.
► The broad near infrared luminescence covers the whole telecommunication window.
► Oxidation of Si into SiO2 is indispensable to activate the Bi luminescence centers.
► There are at least two different kinds of Bi luminescence centers.