Near Infrared Photoluminescence from Yb,Al Co-implanted SiO₂ Films on Silicon

Intense room-temperature near infrared (NIR) photoluminescence (980nm and 1032nm) is observed from Yb,Al co-implanted SiO₂ films on silicon. The optical transitions occur between the ²F_5/2 and ² F_7/2 levels of Yb³⁺ in SiO₂. The additional Al-implantation into SiO₂ films can effectively improve the concentration quenching effect of Yb³⁺ in SiO₂. Photoluminescence excitation spectroscopy shows that the NIR photoluminescence is due to the non-radiative energy transfer from Al-implantation-induced non-bridging oxygen hole defects in SiO₂ to Yb³⁺ in the Yb-related luminescent complexes. It is believed that the defect-mediated luminescence of rare-earth ions in SiO₂ is very effective.